diff --git a/.gitignore b/.gitignore
index 4ba05f7ca698b968eec6391857fa5ec68e1b422e..a3d823fa2182edef86c35ee2810560e5d8f7408e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -26,3 +26,4 @@ Win32_LIB_ASM_Release
 /CMakeUserPresets.json
 /out
 /objs/VC10
+/thirdparty/vcpkg-overlays
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 358e62cc4d5bb72631cbcbe50f7b512a1e97da2a..3b08a9facc348aad76f77b55a5700b8929859333 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -8,7 +8,6 @@ endif()
 set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/cmake/Modules/")
 
 include(CMakeDependentOption)
-include(cmake/CPM.cmake)
 
 file(STRINGS src/version.h SRB2_VERSION)
 string(REGEX MATCH "[0-9]+\\.[0-9.]+" SRB2_VERSION ${SRB2_VERSION})
@@ -46,28 +45,23 @@ SET(CPACK_OUTPUT_FILE_PREFIX package)
 include(CPack)
 
 # Options
-
-if("${CMAKE_SYSTEM_NAME}" MATCHES Linux)
-	set(SRB2_CONFIG_SYSTEM_LIBRARIES_DEFAULT ON)
+if("${CMAKE_SYSTEM_NAME}" MATCHES Windows)
+	if(DEFINED VCPKG_TARGET_TRIPLET)
+		set(SRB2_CONFIG_SYSTEM_LIBRARIES_DEFAULT ON)
+	else()
+		set(SRB2_CONFIG_SYSTEM_LIBRARIES_DEFAULT OFF)
+	endif()
 else()
-	set(SRB2_CONFIG_SYSTEM_LIBRARIES_DEFAULT OFF)
+	set(SRB2_CONFIG_SYSTEM_LIBRARIES_DEFAULT ON)
 endif()
 
 # Clang tidy options will be ignored if CMAKE_<LANG>_CLANG_TIDY are set.
 option(SRB2_CONFIG_ENABLE_CLANG_TIDY_C "Enable default clang-tidy check configuration for C" OFF)
 option(SRB2_CONFIG_ENABLE_CLANG_TIDY_CXX "Enable default clang-tidy check configuration for C++" OFF)
 option(
-	SRB2_CONFIG_SYSTEM_LIBRARIES
-	"Link dependencies using CMake's find_package and do not use internal builds"
-	${SRB2_CONFIG_SYSTEM_LIBRARIES_DEFAULT}
-)
-option(SRB2_CONFIG_ENABLE_TESTS "Build the test suite" ON)
-# This option isn't recommended for distribution builds and probably won't work (yet).
-cmake_dependent_option(
-	SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES
-	"Use dynamic libraries when compiling internal dependencies"
-	OFF "NOT SRB2_CONFIG_SYSTEM_LIBRARIES"
-	OFF
+	SRB2_CONFIG_STATIC_STDLIB
+	"Link static version of standard library. All dependencies must also be static"
+	ON
 )
 option(SRB2_CONFIG_HWRENDER "Enable hardware render (OpenGL) support" ON)
 option(SRB2_CONFIG_USE_GME "Enable GME playback support" OFF)
@@ -82,63 +76,27 @@ option(SRB2_CONFIG_ZDEBUG "Compile with ZDEBUG defined." OFF)
 option(SRB2_CONFIG_PROFILEMODE "Compile for profiling (GCC only)." OFF)
 set(SRB2_CONFIG_ASSET_DIRECTORY "" CACHE PATH "Path to directory that contains all asset files for the installer. If set, assets will be part of installation and cpack.")
 
-if(SRB2_CONFIG_ENABLE_TESTS)
-	# https://github.com/catchorg/Catch2
-	CPMAddPackage(
-		NAME Catch2
-		VERSION 3.4.0
-		GITHUB_REPOSITORY catchorg/Catch2
-		OPTIONS
-			"CATCH_INSTALL_DOCS OFF"
-	)
-	list(APPEND CMAKE_MODULE_PATH "${Catch2_SOURCE_DIR}/extras")
-	include(CTest)
-	include(Catch)
-	add_executable(srb2tests)
-	# To add tests, use target_sources to add individual test files to the target in subdirs.
-	target_link_libraries(srb2tests PRIVATE Catch2::Catch2 Catch2::Catch2WithMain)
-	target_compile_features(srb2tests PRIVATE c_std_11 cxx_std_17)
-	catch_discover_tests(srb2tests)
-endif()
+# Dependencies
+add_subdirectory(thirdparty)
 
-# Enable CCache
-# (Set USE_CCACHE=ON to use, CCACHE_OPTIONS for options)
-if("${CMAKE_HOST_SYSTEM_NAME}" STREQUAL Windows)
-	option(USE_CCACHE "Enable ccache support" OFF)
-
-	if(USE_CCACHE)
-		find_program(CCACHE_TOOL_PATH ccache)
-		if(CCACHE_TOOL_PATH)
-			set(CMAKE_C_COMPILER_LAUNCHER ${CCACHE_TOOL_PATH} CACHE STRING "" FORCE)
-			set(CMAKE_CXX_COMPILER_LAUNCHER ${CCACHE_TOOL_PATH} CACHE STRING "" FORCE)
-		else()
-			message(WARNING "USE_CCACHE was set but ccache is not found (set CCACHE_TOOL_PATH)")
-		endif()
-	endif()
+if(SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES)
+	set(SRB2_INTERNAL_LIBRARY_TYPE SHARED)
+	set(NOT_SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES OFF)
 else()
-	CPMAddPackage(
-		NAME Ccache.cmake
-		GITHUB_REPOSITORY TheLartians/Ccache.cmake
-		VERSION 1.2
-	)
+	set(SRB2_INTERNAL_LIBRARY_TYPE STATIC)
+	set(NOT_SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES ON)
 endif()
 
-# Dependencies
-add_subdirectory(thirdparty)
 
-if("${SRB2_CONFIG_SYSTEM_LIBRARIES}")
-	find_package(ZLIB REQUIRED)
-	find_package(PNG REQUIRED)
-	find_package(SDL2 REQUIRED)
-	find_package(SDL2_mixer REQUIRED)
-	find_package(CURL REQUIRED)
-	find_package(OPENMPT REQUIRED)
-
-	# libgme defaults to "Nuked" YM2612 emulator, which is
-	# very SLOW. The system library probably uses the
-	# default so just always build it.
-	#find_package(GME REQUIRED)
+find_package(ZLIB REQUIRED)
+find_package(PNG REQUIRED)
+find_package(CURL REQUIRED)
+find_package(libopenmpt QUIET)
+if("${SRB2_CONFIG_USE_GME}")
+	find_package(libgme QUIET)
 endif()
+find_package(miniupnpc QUIET)
+
 
 if(${PROJECT_SOURCE_DIR} MATCHES ${PROJECT_BINARY_DIR})
 	message(FATAL_ERROR "In-source builds will bring you a world of pain. Please make a separate directory to invoke CMake from.")
diff --git a/CMakePresets.json b/CMakePresets.json
index effea7260656c6235c75b07669edea01eeb682b7..8cb95d797f7f4c3ae708effa15e0d38112175937 100644
--- a/CMakePresets.json
+++ b/CMakePresets.json
@@ -2,26 +2,263 @@
 	"version": 3,
 	"configurePresets": [
 		{
-			"name": "default",
-			"description": "Build using default generator",
-			"binaryDir": "build",
+			"name": "__debug",
+			"hidden": true,
 			"cacheVariables": {
+				"SRB2_CONFIG_DEV_BUILD": "ON",
+				"CMAKE_BUILD_TYPE": "Debug"
+			}
+		},
+		{
+			"name": "__develop",
+			"hidden": true,
+			"cacheVariables": {
+				"CMAKE_C_FLAGS_RELWITHDEBINFO": "-DNDEBUG",
+				"CMAKE_CXX_FLAGS_RELWITHDEBINFO": "-DNDEBUG",
+				"SRB2_CONFIG_DEV_BUILD": "ON",
 				"CMAKE_BUILD_TYPE": "RelWithDebInfo"
 			}
 		},
 		{
-			"name": "debug",
-			"description": "Build for development (no optimizations)",
-			"inherits": "default",
+			"name": "__release",
+			"hidden": true,
 			"cacheVariables": {
-				"CMAKE_BUILD_TYPE": "Debug"
+				"CMAKE_C_FLAGS_RELWITHDEBINFO": "-DNDEBUG",
+				"CMAKE_CXX_FLAGS_RELWITHDEBINFO": "-DNDEBUG",
+				"SRB2_CONFIG_DEV_BUILD": "OFF",
+				"CMAKE_BUILD_TYPE": "RelWithDebInfo"
+			}
+		},
+		{
+			"name": "__testers",
+			"hidden": true,
+			"cacheVariables": {
+				"CMAKE_C_FLAGS_RELWITHDEBINFO": "-DNDEBUG",
+				"CMAKE_CXX_FLAGS_RELWITHDEBINFO": "-DNDEBUG",
+				"SRB2_CONFIG_DEV_BUILD": "ON",
+				"CMAKE_BUILD_TYPE": "RelWithDebInfo",
+				"SRB2_CONFIG_TESTERS": "ON"
+			}
+		},
+		{
+			"name": "__ninja",
+			"hidden": true,
+			"generator": "Ninja",
+			"cacheVariables": {
+				"CMAKE_COLOR_DIAGNOSTICS": "ON"
+			}
+		},
+		{
+			"name": "__vcpkg-toolchain",
+			"hidden": true,
+			"cacheVariables": {
+				"CMAKE_TOOLCHAIN_FILE": "$env{VCPKG_ROOT}/scripts/buildsystems/vcpkg.cmake"
+			}
+		},
+		{
+			"name": "__compiler-mingw-w64-i686",
+			"hidden": true,
+			"cacheVariables": {
+				"CMAKE_C_COMPILER": "i686-w64-mingw32-gcc",
+				"CMAKE_CXX_COMPILER": "i686-w64-mingw32-g++"
+			}
+		},
+		{
+			"name": "__mingw-dynamic",
+			"hidden": true,
+			"cacheVariables": {
+				"VCPKG_TARGET_TRIPLET": "x86-mingw-dynamic"
 			}
+		},
+		{
+			"name": "__mingw-static",
+			"hidden": true,
+			"cacheVariables": {
+				"VCPKG_HOST_TRIPLET": "x86-mingw-static",
+				"VCPKG_TARGET_TRIPLET": "x86-mingw-static"
+			}
+		},
+		{
+			"name": "__osx_x64",
+			"hidden": true,
+			"cacheVariables": {
+				"VCPKG_TARGET_TRIPLET": "x64-osx"
+			}
+		},
+		{
+			"name": "__osx_arm64",
+			"hidden": true,
+			"cacheVariables": {
+				"VCPKG_TARGET_TRIPLET": "arm64-osx"
+			}
+		},
+
+		{
+			"name": "ninja-debug",
+			"hidden": false,
+			"binaryDir": "build/${presetName}",
+			"inherits": ["__debug", "__ninja"]
+		},
+		{
+			"name": "ninja-develop",
+			"hidden": false,
+			"binaryDir": "build/${presetName}",
+			"inherits": ["__develop", "__ninja"]
+		},
+		{
+			"name": "ninja-release",
+			"hidden": false,
+			"binaryDir": "build/${presetName}",
+			"inherits": ["__release", "__ninja"]
+		},
+		{
+			"name": "ninja-testers",
+			"hidden": false,
+			"binaryDir": "build/${presetName}",
+			"inherits": ["__testers", "__ninja"]
+		},
+
+		{
+			"name": "ninja-vcpkg-debug",
+			"hidden": false,
+			"binaryDir": "build/${presetName}",
+			"inherits": ["__debug", "__ninja", "__vcpkg-toolchain"]
+		},
+		{
+			"name": "ninja-vcpkg-develop",
+			"hidden": false,
+			"binaryDir": "build/${presetName}",
+			"inherits": ["__develop", "__ninja", "__vcpkg-toolchain"]
+		},
+		{
+			"name": "ninja-vcpkg-release",
+			"hidden": false,
+			"binaryDir": "build/${presetName}",
+			"inherits": ["__release", "__ninja", "__vcpkg-toolchain"]
+		},
+		{
+			"name": "ninja-vcpkg-testers",
+			"hidden": false,
+			"binaryDir": "build/${presetName}",
+			"inherits": ["__testers", "__ninja", "__vcpkg-toolchain"]
+		},
+
+		{
+			"name": "ninja-x86_mingw_static_vcpkg-debug",
+			"hidden": false,
+			"binaryDir": "build/${presetName}",
+			"inherits": ["__debug", "__compiler-mingw-w64-i686", "__ninja", "__vcpkg-toolchain", "__mingw-static"]
+		},
+		{
+			"name": "ninja-x86_mingw_static_vcpkg-develop",
+			"hidden": false,
+			"binaryDir": "build/${presetName}",
+			"inherits": ["__develop", "__compiler-mingw-w64-i686", "__ninja", "__vcpkg-toolchain", "__mingw-static"]
+		},
+		{
+			"name": "ninja-x86_mingw_static_vcpkg-release",
+			"hidden": false,
+			"binaryDir": "build/${presetName}",
+			"inherits": ["__release", "__compiler-mingw-w64-i686", "__ninja", "__vcpkg-toolchain", "__mingw-static"]
+		},
+		{
+			"name": "ninja-x86_mingw_static_vcpkg-testers",
+			"hidden": false,
+			"binaryDir": "build/${presetName}",
+			"inherits": ["__testers", "__compiler-mingw-w64-i686", "__ninja", "__vcpkg-toolchain", "__mingw-static"]
+		},
+
+		{
+			"name": "ninja-x64_osx_vcpkg-debug",
+			"hidden": false,
+			"binaryDir": "build/${presetName}",
+			"inherits": ["__debug", "__ninja", "__vcpkg-toolchain", "__osx_x64"]
+		},
+		{
+			"name": "ninja-x64_osx_vcpkg-develop",
+			"hidden": false,
+			"binaryDir": "build/${presetName}",
+			"inherits": ["__develop", "__ninja", "__vcpkg-toolchain", "__osx_x64"]
+		},
+		{
+			"name": "ninja-x64_osx_vcpkg-release",
+			"hidden": false,
+			"binaryDir": "build/${presetName}",
+			"inherits": ["__release", "__ninja", "__vcpkg-toolchain", "__osx_x64"]
+		},
+
+		{
+			"name": "ninja-arm64_osx_vcpkg-debug",
+			"hidden": false,
+			"binaryDir": "build/${presetName}",
+			"inherits": ["__debug", "__ninja", "__vcpkg-toolchain", "__osx_arm64"]
+		},
+		{
+			"name": "ninja-arm64_osx_vcpkg-develop",
+			"hidden": false,
+			"binaryDir": "build/${presetName}",
+			"inherits": ["__develop", "__ninja", "__vcpkg-toolchain", "__osx_arm64"]
+		},
+		{
+			"name": "ninja-arm64_osx_vcpkg-release",
+			"hidden": false,
+			"binaryDir": "build/${presetName}",
+			"inherits": ["__release", "__ninja", "__vcpkg-toolchain", "__osx_arm64"]
 		}
 	],
+
 	"buildPresets": [
 		{
-			"name": "default",
-			"configurePreset": "default"
+			"name": "ninja-debug",
+			"configurePreset": "ninja-debug"
+		},
+		{
+			"name": "ninja-develop",
+			"configurePreset": "ninja-develop"
+		},
+		{
+			"name": "ninja-release",
+			"configurePreset": "ninja-release"
+		},
+		{
+			"name": "ninja-x86_mingw_static_vcpkg-debug",
+			"configurePreset": "ninja-x86_mingw_static_vcpkg-debug"
+		},
+		{
+			"name": "ninja-x86_mingw_static_vcpkg-develop",
+			"configurePreset": "ninja-x86_mingw_static_vcpkg-develop"
+		},
+		{
+			"name": "ninja-x86_mingw_static_vcpkg-release",
+			"configurePreset": "ninja-x86_mingw_static_vcpkg-release"
+		},
+		{
+			"name": "ninja-x86_mingw_static_vcpkg-testers",
+			"configurePreset": "ninja-x86_mingw_static_vcpkg-testers"
+		},
+		{
+			"name": "ninja-x64_osx_vcpkg-debug",
+			"configurePreset": "ninja-x64_osx_vcpkg-debug"
+		},
+		{
+			"name": "ninja-x64_osx_vcpkg-develop",
+			"configurePreset": "ninja-x64_osx_vcpkg-develop"
+		},
+		{
+			"name": "ninja-x64_osx_vcpkg-release",
+			"configurePreset": "ninja-x64_osx_vcpkg-release"
+		},
+		{
+			"name": "ninja-arm64_osx_vcpkg-debug",
+			"configurePreset": "ninja-arm64_osx_vcpkg-debug"
+		},
+		{
+			"name": "ninja-arm64_osx_vcpkg-develop",
+			"configurePreset": "ninja-arm64_osx_vcpkg-develop"
+		},
+		{
+			"name": "ninja-arm64_osx_vcpkg-release",
+			"configurePreset": "ninja-arm64_osx_vcpkg-release"
 		}
 	]
-}
+}
\ No newline at end of file
diff --git a/cmake/CPM.cmake b/cmake/CPM.cmake
deleted file mode 100644
index fba27d2fef3d2bf2edb50ea41687157dc0730c20..0000000000000000000000000000000000000000
--- a/cmake/CPM.cmake
+++ /dev/null
@@ -1,21 +0,0 @@
-set(CPM_DOWNLOAD_VERSION 0.38.7)
-
-if(CPM_SOURCE_CACHE)
-  set(CPM_DOWNLOAD_LOCATION "${CPM_SOURCE_CACHE}/cpm/CPM_${CPM_DOWNLOAD_VERSION}.cmake")
-elseif(DEFINED ENV{CPM_SOURCE_CACHE})
-  set(CPM_DOWNLOAD_LOCATION "$ENV{CPM_SOURCE_CACHE}/cpm/CPM_${CPM_DOWNLOAD_VERSION}.cmake")
-else()
-  set(CPM_DOWNLOAD_LOCATION "${CMAKE_BINARY_DIR}/cmake/CPM_${CPM_DOWNLOAD_VERSION}.cmake")
-endif()
-
-# Expand relative path. This is important if the provided path contains a tilde (~)
-get_filename_component(CPM_DOWNLOAD_LOCATION ${CPM_DOWNLOAD_LOCATION} ABSOLUTE)
-if(NOT (EXISTS ${CPM_DOWNLOAD_LOCATION}))
-  message(STATUS "Downloading CPM.cmake to ${CPM_DOWNLOAD_LOCATION}")
-  file(DOWNLOAD
-       https://github.com/cpm-cmake/CPM.cmake/releases/download/v${CPM_DOWNLOAD_VERSION}/CPM.cmake
-       ${CPM_DOWNLOAD_LOCATION}
-  )
-endif()
-
-include(${CPM_DOWNLOAD_LOCATION})
diff --git a/cmake/Modules/FindGME.cmake b/cmake/Modules/FindGME.cmake
deleted file mode 100644
index 3af0a94be604f44cf0eda200f3d90a129ea77809..0000000000000000000000000000000000000000
--- a/cmake/Modules/FindGME.cmake
+++ /dev/null
@@ -1,33 +0,0 @@
-include(LibFindMacros)
-
-libfind_pkg_check_modules(GME_PKGCONF GME)
-
-find_path(GME_INCLUDE_DIR
-	NAMES gme.h
-	PATHS
-		${GME_PKGCONF_INCLUDE_DIRS}
-		"/usr/include/gme"
-		"/usr/local/include/gme"
-)
-
-find_library(GME_LIBRARY
-	NAMES gme
-	PATHS
-		${GME_PKGCONF_LIBRARY_DIRS}
-		"/usr/lib"
-		"/usr/local/lib"
-)
-
-set(GME_PROCESS_INCLUDES GME_INCLUDE_DIR)
-set(GME_PROCESS_LIBS GME_LIBRARY)
-libfind_process(GME)
-
-if(GME_FOUND AND NOT TARGET gme)
-	add_library(gme UNKNOWN IMPORTED)
-	set_target_properties(
-		gme
-		PROPERTIES
-		IMPORTED_LOCATION "${GME_LIBRARY}"
-		INTERFACE_INCLUDE_DIRECTORIES "${GME_INCLUDE_DIR}"
-	)
-endif()
diff --git a/cmake/Modules/FindOPENMPT.cmake b/cmake/Modules/FindOPENMPT.cmake
deleted file mode 100644
index 7e5b2d5a3966be22d22afdb815934cf20fe0e4d7..0000000000000000000000000000000000000000
--- a/cmake/Modules/FindOPENMPT.cmake
+++ /dev/null
@@ -1,33 +0,0 @@
-include(LibFindMacros)
-
-libfind_pkg_check_modules(OPENMPT_PKGCONF OPENMPT)
-
-find_path(OPENMPT_INCLUDE_DIR
-	NAMES libopenmpt.h
-	PATHS
-		${OPENMPT_PKGCONF_INCLUDE_DIRS}
-		"/usr/include/libopenmpt"
-		"/usr/local/include/libopenmpt"
-)
-
-find_library(OPENMPT_LIBRARY
-	NAMES openmpt
-	PATHS
-		${OPENMPT_PKGCONF_LIBRARY_DIRS}
-		"/usr/lib"
-		"/usr/local/lib"
-)
-
-set(OPENMPT_PROCESS_INCLUDES OPENMPT_INCLUDE_DIR)
-set(OPENMPT_PROCESS_LIBS OPENMPT_LIBRARY)
-libfind_process(OPENMPT)
-
-if(OPENMPT_FOUND AND NOT TARGET openmpt)
-	add_library(openmpt UNKNOWN IMPORTED)
-	set_target_properties(
-		openmpt
-		PROPERTIES
-		IMPORTED_LOCATION "${OPENMPT_LIBRARY}"
-		INTERFACE_INCLUDE_DIRECTORIES "${OPENMPT_INCLUDE_DIR}"
-	)
-endif()
diff --git a/cmake/Modules/Findlibgme.cmake b/cmake/Modules/Findlibgme.cmake
new file mode 100644
index 0000000000000000000000000000000000000000..6b693a7fd14234eb89c24798ea340b6a39030d33
--- /dev/null
+++ b/cmake/Modules/Findlibgme.cmake
@@ -0,0 +1,38 @@
+include(LibFindMacros)
+
+libfind_pkg_check_modules(libgme_PKGCONF gme libgme)
+
+find_path(libgme_INCLUDE_DIR
+	NAMES gme.h
+	PATHS
+		${libgme_PKGCONF_INCLUDE_DIRS}
+		"/usr/include"
+		"/usr/local/include"
+	PATH_SUFFIXES
+		gme
+)
+
+find_library(libgme_LIBRARY
+	NAMES gme
+	PATHS
+		${libgme_PKGCONF_LIBRARY_DIRS}
+		"/usr/lib"
+		"/usr/local/lib"
+)
+
+include(FindPackageHandleStandardArgs)
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(libgme
+    REQUIRED_VARS libgme_LIBRARY libgme_INCLUDE_DIR)
+
+if(libgme_FOUND AND NOT TARGET gme)
+	add_library(gme UNKNOWN IMPORTED)
+	set_target_properties(
+		gme
+		PROPERTIES
+		IMPORTED_LOCATION "${libgme_LIBRARY}"
+		INTERFACE_INCLUDE_DIRECTORIES "${libgme_INCLUDE_DIR}"
+	)
+	add_library(gme::gme ALIAS gme)
+endif()
+
+mark_as_advanced(libgme_LIBRARY libgme_INCLUDE_DIR)
diff --git a/cmake/Modules/Findlibopenmpt.cmake b/cmake/Modules/Findlibopenmpt.cmake
new file mode 100644
index 0000000000000000000000000000000000000000..d7de22134831c1e0edc8b3b6e62ed42abd69287f
--- /dev/null
+++ b/cmake/Modules/Findlibopenmpt.cmake
@@ -0,0 +1,37 @@
+include(LibFindMacros)
+
+libfind_pkg_check_modules(libopenmpt_PKGCONF openmpt)
+
+find_path(libopenmpt_INCLUDE_DIR
+	NAMES libopenmpt.h
+	PATHS
+		${libopenmpt_PKGCONF_INCLUDE_DIRS}
+		"${VCPKG_INSTALLED_DIR}/${VCPKG_TARGET_TRIPLET}/include/libopenmpt"
+		"/usr/include/libopenmpt"
+		"/usr/local/include/libopenmpt"
+)
+
+find_library(libopenmpt_LIBRARY
+	NAMES openmpt
+	PATHS
+		${libopenmpt_PKGCONF_LIBRARY_DIRS}
+		"/usr/lib"
+		"/usr/local/lib"
+)
+
+include(FindPackageHandleStandardArgs)
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(libopenmpt
+    REQUIRED_VARS libopenmpt_LIBRARY libopenmpt_INCLUDE_DIR)
+
+if(libopenmpt_FOUND AND NOT TARGET openmpt)
+	add_library(openmpt UNKNOWN IMPORTED)
+	set_target_properties(
+		openmpt
+		PROPERTIES
+		IMPORTED_LOCATION "${libopenmpt_LIBRARY}"
+		INTERFACE_INCLUDE_DIRECTORIES "${libopenmpt_INCLUDE_DIR}"
+	)
+	add_library(libopenmpt::libopenmpt ALIAS openmpt)
+endif()
+
+mark_as_advanced(libopenmpt_LIBRARY libopenmpt_INCLUDE_DIR)
diff --git a/cmake/Modules/Findminiupnpc.cmake b/cmake/Modules/Findminiupnpc.cmake
new file mode 100644
index 0000000000000000000000000000000000000000..f4931ad832eb856583be1c12daaf4d9883847ed3
--- /dev/null
+++ b/cmake/Modules/Findminiupnpc.cmake
@@ -0,0 +1,39 @@
+include(LibFindMacros)
+
+libfind_pkg_check_modules(libminiupnpc_PKGCONF miniupnpc libminiupnpc)
+
+find_path(libminiupnpc_INCLUDE_DIR
+	NAMES miniupnpc.h
+	PATHS
+		${libminiupnpc_PKGCONF_INCLUDE_DIRS}
+		"${VCPKG_INSTALLED_DIR}/${VCPKG_TARGET_TRIPLET}/include"
+		"/usr/include"
+		"/usr/local/include"
+	PATH_SUFFIXES
+		miniupnpc
+)
+
+find_library(libminiupnpc_LIBRARY
+	NAMES miniupnpc
+	PATHS
+		${libminiupnpc_PKGCONF_LIBRARY_DIRS}
+		"/usr/lib"
+		"/usr/local/lib"
+)
+
+include(FindPackageHandleStandardArgs)
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(miniupnpc
+    REQUIRED_VARS libminiupnpc_LIBRARY libminiupnpc_INCLUDE_DIR)
+
+if(miniupnpc_FOUND AND NOT TARGET miniupnpc)
+	add_library(miniupnpc UNKNOWN IMPORTED)
+	set_target_properties(
+		miniupnpc
+		PROPERTIES
+		IMPORTED_LOCATION "${libminiupnpc_LIBRARY}"
+		INTERFACE_INCLUDE_DIRECTORIES "${libminiupnpc_INCLUDE_DIR}"
+	)
+	add_library(miniupnpc::miniupnpc ALIAS miniupnpc)
+endif()
+
+mark_as_advanced(libminiupnpc_LIBRARY libminiupnpc_INCLUDE_DIR)
diff --git a/cmake/PatchFile.cmake b/cmake/PatchFile.cmake
new file mode 100644
index 0000000000000000000000000000000000000000..f80da3434d764fdbc1eb1f0219c38204517ee19a
--- /dev/null
+++ b/cmake/PatchFile.cmake
@@ -0,0 +1,30 @@
+# use GNU Patch from any platform
+
+if(WIN32)
+  # prioritize Git Patch on Windows as other Patches may be very old and incompatible.
+  find_package(Git)
+  if(Git_FOUND)
+    get_filename_component(GIT_DIR ${GIT_EXECUTABLE} DIRECTORY)
+    get_filename_component(GIT_DIR ${GIT_DIR} DIRECTORY)
+  endif()
+endif()
+
+find_program(PATCH
+NAMES patch
+HINTS ${GIT_DIR}
+PATH_SUFFIXES usr/bin
+)
+
+if(NOT PATCH)
+  message(FATAL_ERROR "Did not find GNU Patch")
+endif()
+
+execute_process(COMMAND ${PATCH} ${in_file} --input=${patch_file} --output=${out_file} --ignore-whitespace
+TIMEOUT 15
+COMMAND_ECHO STDOUT
+RESULT_VARIABLE ret
+)
+
+if(NOT ret EQUAL 0)
+  message(FATAL_ERROR "Failed to apply patch ${patch_file} to ${in_file} with ${PATCH}")
+endif()
\ No newline at end of file
diff --git a/cmake/Toolchains/mingw-w64-i686.cmake b/cmake/Toolchains/mingw-w64-i686.cmake
new file mode 100644
index 0000000000000000000000000000000000000000..6b327291d79d905e7fd97e99196e8b0809fa8d06
--- /dev/null
+++ b/cmake/Toolchains/mingw-w64-i686.cmake
@@ -0,0 +1,16 @@
+set(CMAKE_SYSTEM_NAME Windows)
+set(TOOLCHAIN_PREFIX i686-w64-mingw32)
+
+# cross compilers to use for C, C++ and Fortran
+set(CMAKE_C_COMPILER ${TOOLCHAIN_PREFIX}-gcc)
+set(CMAKE_CXX_COMPILER ${TOOLCHAIN_PREFIX}-g++)
+set(CMAKE_Fortran_COMPILER ${TOOLCHAIN_PREFIX}-gfortran)
+set(CMAKE_RC_COMPILER ${TOOLCHAIN_PREFIX}-windres)
+
+# target environment on the build host system
+set(CMAKE_FIND_ROOT_PATH /usr/${TOOLCHAIN_PREFIX})
+
+# modify default behavior of FIND_XXX() commands
+set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
+set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
+set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
diff --git a/cmake/Toolchains/mingw-w64-x86_64.cmake b/cmake/Toolchains/mingw-w64-x86_64.cmake
new file mode 100644
index 0000000000000000000000000000000000000000..2f22e13d8a5dc80e869c5ca2f0089e5d9917ff7d
--- /dev/null
+++ b/cmake/Toolchains/mingw-w64-x86_64.cmake
@@ -0,0 +1,16 @@
+set(CMAKE_SYSTEM_NAME Windows)
+set(TOOLCHAIN_PREFIX x86_64-w64-mingw32)
+
+# cross compilers to use for C, C++ and Fortran
+set(CMAKE_C_COMPILER ${TOOLCHAIN_PREFIX}-gcc)
+set(CMAKE_CXX_COMPILER ${TOOLCHAIN_PREFIX}-g++)
+set(CMAKE_Fortran_COMPILER ${TOOLCHAIN_PREFIX}-gfortran)
+set(CMAKE_RC_COMPILER ${TOOLCHAIN_PREFIX}-windres)
+
+# target environment on the build host system
+set(CMAKE_FIND_ROOT_PATH /usr/${TOOLCHAIN_PREFIX})
+
+# modify default behavior of FIND_XXX() commands
+set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
+set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
+set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
diff --git a/libs/miniupnpc/include/igd_desc_parse.h b/libs/miniupnpc/include/miniupnpc/igd_desc_parse.h
similarity index 100%
rename from libs/miniupnpc/include/igd_desc_parse.h
rename to libs/miniupnpc/include/miniupnpc/igd_desc_parse.h
diff --git a/libs/miniupnpc/include/miniupnpc.h b/libs/miniupnpc/include/miniupnpc/miniupnpc.h
similarity index 100%
rename from libs/miniupnpc/include/miniupnpc.h
rename to libs/miniupnpc/include/miniupnpc/miniupnpc.h
diff --git a/libs/miniupnpc/include/miniupnpc_declspec.h b/libs/miniupnpc/include/miniupnpc/miniupnpc_declspec.h
similarity index 100%
rename from libs/miniupnpc/include/miniupnpc_declspec.h
rename to libs/miniupnpc/include/miniupnpc/miniupnpc_declspec.h
diff --git a/libs/miniupnpc/include/miniupnpctypes.h b/libs/miniupnpc/include/miniupnpc/miniupnpctypes.h
similarity index 100%
rename from libs/miniupnpc/include/miniupnpctypes.h
rename to libs/miniupnpc/include/miniupnpc/miniupnpctypes.h
diff --git a/libs/miniupnpc/include/miniwget.h b/libs/miniupnpc/include/miniupnpc/miniwget.h
similarity index 100%
rename from libs/miniupnpc/include/miniwget.h
rename to libs/miniupnpc/include/miniupnpc/miniwget.h
diff --git a/libs/miniupnpc/include/portlistingparse.h b/libs/miniupnpc/include/miniupnpc/portlistingparse.h
similarity index 100%
rename from libs/miniupnpc/include/portlistingparse.h
rename to libs/miniupnpc/include/miniupnpc/portlistingparse.h
diff --git a/libs/miniupnpc/include/upnpcommands.h b/libs/miniupnpc/include/miniupnpc/upnpcommands.h
similarity index 100%
rename from libs/miniupnpc/include/upnpcommands.h
rename to libs/miniupnpc/include/miniupnpc/upnpcommands.h
diff --git a/libs/miniupnpc/include/upnpdev.h b/libs/miniupnpc/include/miniupnpc/upnpdev.h
similarity index 100%
rename from libs/miniupnpc/include/upnpdev.h
rename to libs/miniupnpc/include/miniupnpc/upnpdev.h
diff --git a/libs/miniupnpc/include/upnperrors.h b/libs/miniupnpc/include/miniupnpc/upnperrors.h
similarity index 100%
rename from libs/miniupnpc/include/upnperrors.h
rename to libs/miniupnpc/include/miniupnpc/upnperrors.h
diff --git a/libs/miniupnpc/include/upnpreplyparse.h b/libs/miniupnpc/include/miniupnpc/upnpreplyparse.h
similarity index 100%
rename from libs/miniupnpc/include/upnpreplyparse.h
rename to libs/miniupnpc/include/miniupnpc/upnpreplyparse.h
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 486f4e913057af02c22a6acd6c554bd7b76801b3..20caecf7bd6a65a20631318799016da319d3f13d 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -134,10 +134,13 @@ add_dependencies(SRB2SDL2 _SRB2_reconf)
 
 if("${CMAKE_COMPILER_IS_GNUCC}" AND "${CMAKE_SYSTEM_NAME}" MATCHES "Windows")
 	target_link_options(SRB2SDL2 PRIVATE "-Wl,--disable-dynamicbase")
-	if(NOT "${SRB2_CONFIG_SYSTEM_LIBRARIES}" AND NOT "${SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES}")
+	if("${SRB2_CONFIG_STATIC_STDLIB}")
 		# On MinGW with internal libraries, link the standard library statically
 		target_link_options(SRB2SDL2 PRIVATE "-static")
 	endif()
+	if(CMAKE_SIZEOF_VOID_P EQUAL 4)
+		target_link_options(SRB2SDL2 PRIVATE "-Wl,--large-address-aware")
+	endif()
 endif()
 
 target_compile_features(SRB2SDL2 PRIVATE c_std_11 cxx_std_17)
@@ -182,12 +185,7 @@ if("${SRB2_CONFIG_USE_GME}")
 	endif()
 endif()
 
-target_link_libraries(SRB2SDL2 PRIVATE openmpt)
-target_compile_definitions(SRB2SDL2 PRIVATE -DHAVE_OPENMPT)
-
-target_link_libraries(SRB2SDL2 PRIVATE ZLIB::ZLIB PNG::PNG CURL::libcurl)
-target_compile_definitions(SRB2SDL2 PRIVATE -DHAVE_ZLIB -DHAVE_PNG -DHAVE_CURL -D_LARGEFILE64_SOURCE)
-target_sources(SRB2SDL2 PRIVATE apng.c)
+target_compile_definitions(SRB2SDL2 PRIVATE -D_LARGEFILE64_SOURCE)
 
 set(SRB2_HAVE_THREADS ON)
 target_compile_definitions(SRB2SDL2 PRIVATE -DHAVE_THREADS)
@@ -403,8 +401,66 @@ if(SRB2_CONFIG_PROFILEMODE AND "${CMAKE_C_COMPILER_ID}" STREQUAL "GNU")
 endif()
 
 add_subdirectory(sdl)
-if(SRB2_CONFIG_ENABLE_TESTS)
-	add_subdirectory(tests)
+
+if(TARGET ZLIB::ZLIB)
+	target_compile_definitions(SRB2SDL2 PRIVATE -DHAVE_ZLIB)
+	message(STATUS "Zlib Found")
+else()
+	message(STATUS "No Zlib Found")
+endif()
+
+if(TARGET PNG::PNG)
+	target_compile_definitions(SRB2SDL2 PRIVATE -DHAVE_PNG)
+	target_sources(SRB2SDL2 PRIVATE apng.c ${libapng_HEADER})
+	target_include_directories(SRB2SDL2 PRIVATE ${libapng_INCLUDE_DIRS} ${libpng_BINARY_DIR})
+	#message(STATUS "libpng inc DIRS at ${libapng_INCLUDE_DIRS}")
+	#message(STATUS "libpng bin DIRS at ${libpng_BINARY_DIR}")
+	#message(STATUS "png.h at ${libapng_HEADER}")
+	message(STATUS "libpng Found")
+else()
+	message(STATUS "No libpng Found")
+endif()
+
+if(TARGET PNG::PNG AND TARGET ZLIB::ZLIB)
+#libpng links zlib too?
+target_link_libraries(SRB2SDL2 PRIVATE PNG::PNG)
+endif()
+
+if(NOT TARGET PNG::PNG AND TARGET ZLIB::ZLIB)
+#got no libpng? we need zlib
+target_link_libraries(SRB2SDL2 PRIVATE ZLIB::ZLIB)
+endif()
+
+if(TARGET gme::gme)
+	target_compile_definitions(SRB2SDL2 PRIVATE -DHAVE_GME)
+	target_link_libraries(SRB2SDL2 PRIVATE gme::gme)
+	message(STATUS "libgme Found")
+else()
+	message(STATUS "No libgme Found")
+endif()
+
+if(TARGET libopenmpt::libopenmpt)
+	target_compile_definitions(SRB2SDL2 PRIVATE -DHAVE_OPENMPT)
+	target_link_libraries(SRB2SDL2 PRIVATE libopenmpt::libopenmpt)
+	message(STATUS "libopenmpt Found")
+else()
+	message(STATUS "No libopenmpt Found")
+endif()
+
+if(TARGET CURL::libcurl)
+	target_compile_definitions(SRB2SDL2 PRIVATE -DHAVE_CURL)
+	target_link_libraries(SRB2SDL2 PRIVATE CURL::libcurl)
+	message(STATUS "libcurl Found")
+else()
+	message(STATUS "No libcurl Found")
+endif()
+
+if(TARGET miniupnpc::miniupnpc)
+	target_compile_definitions(SRB2SDL2 PRIVATE -DHAVE_MINIUPNPC)
+	target_link_libraries(SRB2SDL2 PRIVATE miniupnpc::miniupnpc)
+	message(STATUS "miniupnpc Found")
+else()
+	message(STATUS "No miniupnpc Found")
 endif()
 
 # strip debug symbols into separate file when using gcc.
diff --git a/src/deh_lua.c b/src/deh_lua.c
index c056db82a7ca65c7bb9c1ba363708ce5880d253f..64fb52fc7423a7486c9d6736762fedd0fcde64ba 100644
--- a/src/deh_lua.c
+++ b/src/deh_lua.c
@@ -59,24 +59,19 @@ static inline int lib_freeslot(lua_State *L)
 		}
 		else if (fastcmp(type, "SPR"))
 		{
-			char wad;
 			spritenum_t j;
-			lua_getfield(L, LUA_REGISTRYINDEX, "WAD");
-			wad = (char)lua_tointeger(L, -1);
-			lua_pop(L, 1);
+
+			if (strlen(word) > MAXSPRITENAME)
+				return luaL_error(L, "Sprite name is longer than %d characters\n", MAXSPRITENAME);
+
 			for (j = SPR_FIRSTFREESLOT; j <= SPR_LASTFREESLOT; j++)
 			{
-				if (used_spr[(j-SPR_FIRSTFREESLOT)/8] & (1<<(j%8)))
-				{
-					if (!sprnames[j][4] && memcmp(sprnames[j],word,4)==0)
-						sprnames[j][4] = wad;
+				if (in_bit_array(used_spr, j - SPR_FIRSTFREESLOT))
 					continue; // Already allocated, next.
-				}
 				// Found a free slot!
 				CONS_Printf("Sprite SPR_%s allocated.\n",word);
-				strncpy(sprnames[j],word,4);
-				//sprnames[j][4] = 0;
-				used_spr[(j-SPR_FIRSTFREESLOT)/8] |= 1<<(j%8); // Okay, this sprite slot has been named now.
+				strcpy(sprnames[j], word);
+				set_bit_array(used_spr, j - SPR_FIRSTFREESLOT); // Okay, this sprite slot has been named now.
 				// Lua needs to update the value in _G if it exists
 				LUA_UpdateSprName(word, j);
 				lua_pushinteger(L, j);
@@ -455,17 +450,19 @@ static int ScanConstants(lua_State *L, boolean mathlib, const char *word)
 	}
 	else if (fastncmp("SPR_",word,4)) {
 		p = word+4;
-		for (i = 0; i < NUMSPRITES; i++)
-			if (!sprnames[i][4] && fastncmp(p,sprnames[i],4)) {
-				// updating overridden sprnames is not implemented for soc parser,
-				// so don't use cache
-				if (mathlib)
-					lua_pushinteger(L, i);
-				else
-					CacheAndPushConstant(L, word, i);
-				return 1;
-			}
-		if (mathlib) return luaL_error(L, "sprite '%s' could not be found.\n", word);
+		i = R_GetSpriteNumByName(p);
+		if (i != NUMSPRITES)
+		{
+			// updating overridden sprnames is not implemented for soc parser,
+			// so don't use cache
+			if (mathlib)
+				lua_pushinteger(L, i);
+			else
+				CacheAndPushConstant(L, word, i);
+			return 1;
+		}
+		else if (mathlib)
+			return luaL_error(L, "sprite '%s' could not be found.\n", word);
 		return 0;
 	}
 	else if (fastncmp("SPR2_",word,5)) {
@@ -738,18 +735,18 @@ static inline int lib_getenum(lua_State *L)
 // If a sprname has been "cached" to _G, update it to a new value.
 void LUA_UpdateSprName(const char *name, lua_Integer value)
 {
-	char fullname[9] = "SPR_XXXX";
+	char fullname[4 + MAXSPRITENAME + 1] = "SPR_";
 
 	if (!gL)
 		return;
 
-	strncpy(&fullname[4], name, 4);
+	strcpy(&fullname[4], name);
 	lua_pushstring(gL, fullname);
 	lua_rawget(gL, LUA_GLOBALSINDEX);
 
 	if (!lua_isnil(gL, -1))
 	{
-		lua_pushstring(gL, name);
+		lua_pushstring(gL, fullname);
 		lua_pushinteger(gL, value);
 		lua_rawset(gL, LUA_GLOBALSINDEX);
 	}
diff --git a/src/deh_soc.c b/src/deh_soc.c
index 65db63ebb13fab76dc84dbbfb64f43fa13a8895f..d1643fd4eda3b8f141b410ab57286c04f90381fe 100644
--- a/src/deh_soc.c
+++ b/src/deh_soc.c
@@ -440,18 +440,16 @@ void readfreeslots(MYFILE *f)
 				S_AddSoundFx(word, false, 0, false);
 			else if (fastcmp(type, "SPR"))
 			{
+				if (strlen(word) > MAXSPRITENAME)
+					I_Error("Sprite name is longer than %d characters\n", MAXSPRITENAME);
+
 				for (i = SPR_FIRSTFREESLOT; i <= SPR_LASTFREESLOT; i++)
 				{
-					if (used_spr[(i-SPR_FIRSTFREESLOT)/8] & (1<<(i%8)))
-					{
-						if (!sprnames[i][4] && memcmp(sprnames[i],word,4)==0)
-							sprnames[i][4] = (char)f->wad;
+					if (in_bit_array(used_spr, i - SPR_FIRSTFREESLOT))
 						continue; // Already allocated, next.
-					}
 					// Found a free slot!
-					strncpy(sprnames[i],word,4);
-					//sprnames[i][4] = 0;
-					used_spr[(i-SPR_FIRSTFREESLOT)/8] |= 1<<(i%8); // Okay, this sprite slot has been named now.
+					strcpy(sprnames[i], word);
+					set_bit_array(used_spr, i - SPR_FIRSTFREESLOT); // Okay, this sprite slot has been named now.
 					// Lua needs to update the value in _G if it exists
 					LUA_UpdateSprName(word, i);
 					break;
@@ -4182,9 +4180,9 @@ spritenum_t get_sprite(const char *word)
 		return atoi(word);
 	if (fastncmp("SPR_",word,4))
 		word += 4; // take off the SPR_
-	for (i = 0; i < NUMSPRITES; i++)
-		if (!sprnames[i][4] && memcmp(word,sprnames[i],4)==0)
-			return i;
+	i = R_GetSpriteNumByName(word);
+	if (i != NUMSPRITES)
+		return i;
 	deh_warning("Couldn't find sprite named 'SPR_%s'",word);
 	return SPR_NULL;
 }
diff --git a/src/deh_tables.c b/src/deh_tables.c
index ed401d68a320188560783872e9c5672d6a41993d..c7c7c604068cd4761ea3944a92cd4efecd9a0ddb 100644
--- a/src/deh_tables.c
+++ b/src/deh_tables.c
@@ -31,7 +31,7 @@
 char *FREE_STATES[NUMSTATEFREESLOTS];
 char *FREE_MOBJS[NUMMOBJFREESLOTS];
 char *FREE_SKINCOLORS[NUMCOLORFREESLOTS];
-UINT8 used_spr[(NUMSPRITEFREESLOTS / 8) + 1]; // Bitwise flag for sprite freeslot in use! I would use ceil() here if I could, but it only saves 1 byte of memory anyway.
+bitarray_t used_spr[BIT_ARRAY_SIZE(NUMSPRITEFREESLOTS)]; // Sprite freeslots in use
 
 const char NIGHTSGRADE_LIST[] = {
 	'F', // GRADE_F
diff --git a/src/deh_tables.h b/src/deh_tables.h
index 42716f9b4bd271c98aca83737f419670d862d7e5..b6986adff0166c3132be5f70ca78c7835030998f 100644
--- a/src/deh_tables.h
+++ b/src/deh_tables.h
@@ -23,13 +23,13 @@
 extern char *FREE_STATES[NUMSTATEFREESLOTS];
 extern char *FREE_MOBJS[NUMMOBJFREESLOTS];
 extern char *FREE_SKINCOLORS[NUMCOLORFREESLOTS];
-extern UINT8 used_spr[(NUMSPRITEFREESLOTS / 8) + 1]; // Bitwise flag for sprite freeslot in use! I would use ceil() here if I could, but it only saves 1 byte of memory anyway.
+extern bitarray_t used_spr[BIT_ARRAY_SIZE(NUMSPRITEFREESLOTS)]; // Sprite freeslots in use
 
 #define initfreeslots() {\
-	memset(FREE_STATES,0,sizeof(char *) * NUMSTATEFREESLOTS);\
-	memset(FREE_MOBJS,0,sizeof(char *) * NUMMOBJFREESLOTS);\
-	memset(FREE_SKINCOLORS,0,sizeof(char *) * NUMCOLORFREESLOTS);\
-	memset(used_spr,0,sizeof(UINT8) * ((NUMSPRITEFREESLOTS / 8) + 1));\
+	memset(FREE_STATES, 0, sizeof(FREE_STATES));\
+	memset(FREE_MOBJS, 0, sizeof(FREE_MOBJS));\
+	memset(FREE_SKINCOLORS, 0, sizeof(FREE_SKINCOLORS));\
+	memset(used_spr, 0, sizeof(used_spr));\
 	memset(actionsoverridden, LUA_REFNIL, sizeof(actionsoverridden));\
 }
 
diff --git a/src/filesrch.c b/src/filesrch.c
index 6429b6fa2f13b49979c7e5efa1614bf47cac02be..944e8447f4d462c5ee7cac302a7481422e184613 100644
--- a/src/filesrch.c
+++ b/src/filesrch.c
@@ -1185,7 +1185,7 @@ boolean preparefilemenu(boolean samedepth)
 					{
 						if (!filenamebuf[i][0])
 						{
-							strncpy(filenamebuf[i], wadfiles[i]->filename, MAX_WADPATH);
+							strncpy(filenamebuf[i], wadfiles[i]->filename, MAX_WADPATH-1);
 							filenamebuf[i][MAX_WADPATH - 1] = '\0';
 							nameonly(filenamebuf[i]);
 						}
diff --git a/src/hardware/hw_md2.c b/src/hardware/hw_md2.c
index 656fbc4a68b12302f524229aee1b8223f0baaa6e..0bb8de851bd2ad1b1891b92322943df83d349539 100644
--- a/src/hardware/hw_md2.c
+++ b/src/hardware/hw_md2.c
@@ -571,19 +571,15 @@ void HWR_LoadModels(void)
 		}
 
 		// Add sprite models.
-		// Must be 4 characters long exactly. Otherwise, it's not a sprite name.
-		if (len == 4)
+		for (i = 0; i < numsprites; i++)
 		{
-			for (i = 0; i < numsprites; i++)
+			if (stricmp(name, sprnames[i]) == 0)
 			{
-				if (stricmp(name, sprnames[i]) == 0)
-				{
-					md2_models[i].scale = scale;
-					md2_models[i].offset = offset;
-					md2_models[i].found = true;
-					strcpy(md2_models[i].filename, filename);
-					goto modelfound;
-				}
+				md2_models[i].scale = scale;
+				md2_models[i].offset = offset;
+				md2_models[i].found = true;
+				strcpy(md2_models[i].filename, filename);
+				goto modelfound;
 			}
 		}
 
diff --git a/src/info.c b/src/info.c
index ab46cdbc728de4d8d71c39e97adf245235301acc..9b33a57ab2f863d24f2355b24acdd6ed208e9765 100644
--- a/src/info.c
+++ b/src/info.c
@@ -26,9 +26,10 @@
 #include "hardware/hw_light.h"
 #endif
 
+
 // Hey, moron! If you change this table, don't forget about the sprite enum in info.h and the sprite lights in hw_light.c!
 // For the sake of constant merge conflicts, let's spread this out
-char sprnames[NUMSPRITES + 1][5] =
+char sprnames[NUMSPRITES + 1][MAXSPRITENAME + 1] =
 {
 	"NULL", // invisible object
 	"UNKN",
@@ -525,7 +526,7 @@ char sprnames[NUMSPRITES + 1][5] =
 	"GWLR",
 };
 
-char spr2names[NUMPLAYERSPRITES][5] =
+char spr2names[NUMPLAYERSPRITES][MAXSPRITENAME + 1] =
 {
 	"STND",
 	"WAIT",
diff --git a/src/info.h b/src/info.h
index 9475b2302852c6ff2f1ad37cda5706eda9410b0e..0361f64281150bec03676bd1b8a4baa36a18de22 100644
--- a/src/info.h
+++ b/src/info.h
@@ -575,6 +575,7 @@ extern int actionsoverridden[NUMACTIONS][MAX_ACTION_RECURSION];
 #define NUMMOBJFREESLOTS 1024
 #define NUMSPRITEFREESLOTS NUMMOBJFREESLOTS
 #define NUMSTATEFREESLOTS (NUMMOBJFREESLOTS*8)
+#define MAXSPRITENAME 64
 
 // Hey, moron! If you change this table, don't forget about sprnames in info.c and the sprite lights in hw_light.c!
 typedef enum sprite
@@ -4383,8 +4384,8 @@ typedef struct
 } state_t;
 
 extern state_t states[NUMSTATES];
-extern char sprnames[NUMSPRITES + 1][5];
-extern char spr2names[NUMPLAYERSPRITES][5];
+extern char sprnames[NUMSPRITES + 1][MAXSPRITENAME + 1];
+extern char spr2names[NUMPLAYERSPRITES][MAXSPRITENAME + 1];
 extern playersprite_t spr2defaults[NUMPLAYERSPRITES];
 extern state_t *astate;
 extern playersprite_t free_spr2;
diff --git a/src/lua_baselib.c b/src/lua_baselib.c
index 9e4eebeb08fd5b84b59c580f8221a1fa05b4b3f8..f6b8f462b5a41cee30c33145fd62fa28daa01e92 100644
--- a/src/lua_baselib.c
+++ b/src/lua_baselib.c
@@ -3030,6 +3030,9 @@ static int lib_rFrame2Char(lua_State *L)
 	//HUDSAFE
 
 	c[0] = R_Frame2Char(ch);
+	if (c[0] == '\xFF')
+		return luaL_error(L, "frame %u cannot be represented by a character", ch);
+
 	c[1] = 0;
 
 	lua_pushstring(L, c);
diff --git a/src/lua_hudlib.c b/src/lua_hudlib.c
index ddd6c688802076a913a8d55d3597d1b9aafc9454..d6771f1082a635e2bcb9e26ffb4349398113397c 100644
--- a/src/lua_hudlib.c
+++ b/src/lua_hudlib.c
@@ -492,9 +492,7 @@ static int libd_getSpritePatch(lua_State *L)
 	else if (lua_isstring(L, 1)) // sprite prefix name given, e.g. "THOK"
 	{
 		const char *name = lua_tostring(L, 1);
-		for (i = 0; i < NUMSPRITES; i++)
-			if (fastcmp(name, sprnames[i]))
-				break;
+		i = R_GetSpriteNumByName(name);
 		if (i >= NUMSPRITES)
 			return 0;
 	}
diff --git a/src/lua_infolib.c b/src/lua_infolib.c
index 0bcbcc5b983da37130a1ef7a1133c3a9b7193ea3..eeb1067a335f121f23d89bcf817a0b54f53f4f41 100644
--- a/src/lua_infolib.c
+++ b/src/lua_infolib.c
@@ -88,12 +88,12 @@ static int lib_getSprname(lua_State *L)
 	else if (lua_isstring(L, 1))
 	{
 		const char *name = lua_tostring(L, 1);
-		for (i = 0; i < NUMSPRITES; i++)
-			if (fastcmp(name, sprnames[i]))
-			{
-				lua_pushinteger(L, i);
-				return 1;
-			}
+		i = R_GetSpriteNumByName(name);
+		if (i != NUMSPRITES)
+		{
+			lua_pushinteger(L, i);
+			return 1;
+		}
 	}
 	return 0;
 }
@@ -245,22 +245,15 @@ static int lib_getSpriteInfo(lua_State *L)
 	if (lua_isstring(L, 1))
 	{
 		const char *name = lua_tostring(L, 1);
-		INT32 spr;
-		for (spr = 0; spr < NUMSPRITES; spr++)
-		{
-			if (fastcmp(name, sprnames[spr]))
-			{
-				i = spr;
-				break;
-			}
-		}
-		if (i == NUMSPRITES)
+		INT32 spr = R_GetSpriteNumByName(name);
+		if (spr == NUMSPRITES)
 		{
 			char *check;
 			i = strtol(name, &check, 10);
 			if (check == name || *check != '\0')
 				return luaL_error(L, "unknown sprite name %s", name);
 		}
+		i = spr;
 	}
 	else
 		i = luaL_checkinteger(L, 1);
@@ -359,8 +352,8 @@ static int PopPivotTable(spriteinfo_t *info, lua_State *L, int stk)
 			default:
 				TYPEERROR("pivot frame", LUA_TNUMBER, lua_type(L, stk+1));
 		}
-		if ((idx < 0) || (idx >= 64))
-			return luaL_error(L, "pivot frame %d out of range (0 - %d)", idx, 63);
+		if ((idx < 0) || (idx >= MAXFRAMENUM))
+			return luaL_error(L, "pivot frame %d out of range (0 - %d)", idx, MAXFRAMENUM - 1);
 		// the values in pivot[] are also tables
 		if (PopPivotSubTable(info->pivot, L, stk+2, idx))
 			info->available = true;
@@ -555,7 +548,7 @@ static int pivotlist_set(lua_State *L)
 
 static int pivotlist_num(lua_State *L)
 {
-	lua_pushinteger(L, 64);
+	lua_pushinteger(L, MAXFRAMENUM);
 	return 1;
 }
 
diff --git a/src/lua_script.c b/src/lua_script.c
index b62fa675e2e7193da3a688d89d2f1cf377298a51..057899555480383611652c552e41bf41398b0e2b 100644
--- a/src/lua_script.c
+++ b/src/lua_script.c
@@ -622,9 +622,6 @@ static inline boolean LUA_LoadFile(MYFILE *f, char *name)
 	if (!gL) // Lua needs to be initialized
 		LUA_ClearState();
 
-	lua_pushinteger(gL, f->wad);
-	lua_setfield(gL, LUA_REGISTRYINDEX, "WAD");
-
 	lua_pushcfunction(gL, LUA_GetErrorMessage);
 	errorhandlerindex = lua_gettop(gL);
 
diff --git a/src/netcode/i_tcp.c b/src/netcode/i_tcp.c
index 0148c485ab1fd5fd29cd4ca0bc6effca93ff69f1..6a50f440be80cfee5a591ed757ae1c79414c6455 100644
--- a/src/netcode/i_tcp.c
+++ b/src/netcode/i_tcp.c
@@ -114,16 +114,10 @@ typedef union
 } mysockaddr_t;
 
 	#ifdef HAVE_MINIUPNPC
-	#ifdef MINIUPNP_STATICLIB
-		#include "miniwget.h"
-		#include "miniupnpc.h"
-		#include "upnpcommands.h"
-	#else
-		#include "miniupnpc/miniwget.h"
-		#include "miniupnpc/miniupnpc.h"
-		#include "miniupnpc/upnpcommands.h"
-	#endif
-		static boolean UPNP_support = true;
+	#include "miniupnpc/miniwget.h"
+	#include "miniupnpc/miniupnpc.h"
+	#include "miniupnpc/upnpcommands.h"
+	static boolean UPNP_support = true;
 	#endif // HAVE_MINIUPNC
 
 #define MAXBANS 100
diff --git a/src/p_inter.c b/src/p_inter.c
index 406f4af2227d294adb2883433009b4699b9881bf..e73cd1fce675ee17721e6236e7dc764ede8e9d69 100644
--- a/src/p_inter.c
+++ b/src/p_inter.c
@@ -1365,7 +1365,7 @@ void P_TouchSpecialThing(mobj_t *special, mobj_t *toucher, boolean heightcheck)
 			}
 			break;
 		case MT_NIGHTSEXTRATIME:
-			if ((player->bot && player->bot != BOT_MPAI) || !(player->powers[pw_carry] == CR_NIGHTSMODE))
+			if ((player->bot && player->bot != BOT_MPAI) || !(player->powers[pw_carry] == CR_NIGHTSMODE || (G_IsSpecialStage(gamemap) && !(maptol & TOL_NIGHTS))))
 				return;
 			if (!G_IsSpecialStage(gamemap))
 			{
@@ -1377,7 +1377,7 @@ void P_TouchSpecialThing(mobj_t *special, mobj_t *toucher, boolean heightcheck)
 			else
 			{
 				for (i = 0; i < MAXPLAYERS; i++)
-					if (playeringame[i] && players[i].powers[pw_carry] == CR_NIGHTSMODE)
+					if (playeringame[i] && (player->powers[pw_carry] == CR_NIGHTSMODE || (G_IsSpecialStage(gamemap) && !(maptol & TOL_NIGHTS))))
 					{
 						players[i].nightstime += special->info->speed;
 						players[i].startedtime += special->info->speed;
@@ -3640,7 +3640,7 @@ void P_SpecialStageDamage(player_t *player, mobj_t *inflictor, mobj_t *source)
 		if (player->nightstime > 5*TICRATE)
 			player->nightstime -= 5*TICRATE;
 		else
-			player->nightstime = 0;
+			player->nightstime = 1;
 	}
 
 	P_DoPlayerPain(player, inflictor, source);
diff --git a/src/p_pspr.h b/src/p_pspr.h
index be0d9f39e37369543ea70d74e1558ebb5ca4aa36..5fb6767633398d1e304001123dcda541599b1aba 100644
--- a/src/p_pspr.h
+++ b/src/p_pspr.h
@@ -35,7 +35,7 @@
 #pragma interface
 #endif
 
-/// \brief Frame flags: only the frame number - 0 to 256 (Frames from 0 to 63, Sprite2 number uses 0 to 127 plus FF_SPR2SUPER)
+/// \brief Frame flags: only the frame number - 0 to 256 (Frames from 0 to 255, Sprite2 number uses 0 to 127 plus FF_SPR2SUPER)
 #define FF_FRAMEMASK 0xff
 
 /// \brief Frame flags - SPR2: Super sprite2
diff --git a/src/p_tick.c b/src/p_tick.c
index 6d7d4fd969fb70964e4e0cf6663d26bd6d81e8a7..56e0fd897bfbba718885a1104224d1554790f227 100644
--- a/src/p_tick.c
+++ b/src/p_tick.c
@@ -564,6 +564,12 @@ void P_DoTeamscrambling(void)
 		CV_SetValue(&cv_teamscramble, 0);
 }
 
+
+//
+// P_DoSpecialStageStuff()
+//
+// For old-style (non-NiGHTS) special stages
+//
 static inline void P_DoSpecialStageStuff(void)
 {
 	boolean stillalive = false;
@@ -601,7 +607,15 @@ static inline void P_DoSpecialStageStuff(void)
 				if (--players[i].nightstime > 6)
 				{
 					if (P_IsLocalPlayer(&players[i]) && oldnightstime > 10*TICRATE && players[i].nightstime <= 10*TICRATE)
-						S_ChangeMusicInternal("_drown", false);
+					{
+						if (mapheaderinfo[gamemap-1]->levelflags & LF_MIXNIGHTSCOUNTDOWN)
+						{
+							S_FadeMusic(0, 10*MUSICRATE);
+							S_StartSound(NULL, sfx_timeup); // that creepy "out of time" music from NiGHTS.
+						}
+						else
+							S_ChangeMusicInternal("_drown", false);
+					}
 					stillalive = true;
 				}
 				else if (!players[i].exiting)
diff --git a/src/r_defs.h b/src/r_defs.h
index cb94dd6e5a5641970b216e88ce9183d66d186e63..da4dd2d70e6049479eacd24c51af11b4a995507b 100644
--- a/src/r_defs.h
+++ b/src/r_defs.h
@@ -976,6 +976,8 @@ typedef struct
 #endif
 } spriteframe_t;
 
+#define MAXFRAMENUM 256
+
 //
 // A sprite definition:  a number of animation frames.
 //
diff --git a/src/r_picformats.c b/src/r_picformats.c
index e4a59f2115d3833b3f5a76e38ff4a1cdd7d4ce30..d71657021b6e2cc91efe504b49286f459461095d 100644
--- a/src/r_picformats.c
+++ b/src/r_picformats.c
@@ -1570,7 +1570,7 @@ static void R_ParseSpriteInfo(boolean spr2)
 	spriteinfo_t *info;
 	char *sprinfoToken;
 	size_t sprinfoTokenLength;
-	char newSpriteName[5]; // no longer dynamically allocated
+	char newSpriteName[MAXSPRITENAME + 1]; // no longer dynamically allocated
 	spritenum_t sprnum = NUMSPRITES;
 	playersprite_t spr2num = NUMPLAYERSPRITES;
 	INT32 i;
@@ -1584,31 +1584,17 @@ static void R_ParseSpriteInfo(boolean spr2)
 		I_Error("Error parsing SPRTINFO lump: Unexpected end of file where sprite name should be");
 	}
 	sprinfoTokenLength = strlen(sprinfoToken);
-	if (sprinfoTokenLength != 4)
-	{
-		I_Error("Error parsing SPRTINFO lump: Sprite name \"%s\" isn't 4 characters long",sprinfoToken);
-	}
-	else
-	{
-		memset(&newSpriteName, 0, 5);
-		M_Memcpy(newSpriteName, sprinfoToken, sprinfoTokenLength);
-		// ^^ we've confirmed that the token is == 4 characters so it will never overflow a 5 byte char buffer
-		strupr(newSpriteName); // Just do this now so we don't have to worry about it
-	}
+	if (sprinfoTokenLength > MAXSPRITENAME)
+		I_Error("Error parsing SPRTINFO lump: Sprite name \"%s\" is longer than %d characters", sprinfoToken, MAXSPRITENAME);
+	strcpy(newSpriteName, sprinfoToken);
+	strupr(newSpriteName); // Just do this now so we don't have to worry about it
 	Z_Free(sprinfoToken);
 
 	if (!spr2)
 	{
-		for (i = 0; i <= NUMSPRITES; i++)
-		{
-			if (i == NUMSPRITES)
-				I_Error("Error parsing SPRTINFO lump: Unknown sprite name \"%s\"", newSpriteName);
-			if (!memcmp(newSpriteName,sprnames[i],4))
-			{
-				sprnum = i;
-				break;
-			}
-		}
+		sprnum = R_GetSpriteNumByName(newSpriteName);
+		if (sprnum == NUMSPRITES)
+			I_Error("Error parsing SPRTINFO lump: Unknown sprite name \"%s\"", newSpriteName);
 	}
 	else
 	{
diff --git a/src/r_picformats.h b/src/r_picformats.h
index 3ee9805d867f30cf8eec923285b24d0172038f18..098f927a5619d74ca9813d37658d5bfb75bc8f04 100644
--- a/src/r_picformats.h
+++ b/src/r_picformats.h
@@ -100,7 +100,7 @@ typedef struct
 
 typedef struct
 {
-	spriteframepivot_t pivot[64];
+	spriteframepivot_t pivot[MAXFRAMENUM];
 	boolean available;
 } spriteinfo_t;
 
diff --git a/src/r_skins.c b/src/r_skins.c
index 29a1556c0f6805fa788f1334628242c80570492f..d0d2eed6287ed69b27fef7eb7fe3acc4c7c61b3c 100644
--- a/src/r_skins.c
+++ b/src/r_skins.c
@@ -625,7 +625,7 @@ static void R_LoadSkinSprites(UINT16 wadnum, UINT16 *lump, UINT16 *lastlump, ski
 		newlastlump++;
 		// load all sprite sets we are aware of... for super!
 		for (sprite2 = start_spr2; sprite2 < free_spr2; sprite2++)
-			R_AddSingleSpriteDef(spr2names[sprite2], &skin->super.sprites[sprite2], wadnum, newlastlump, *lastlump);
+			R_AddSingleSpriteDef(spr2names[sprite2], &skin->super.sprites[sprite2], wadnum, newlastlump, *lastlump, false);
 
 		newlastlump--;
 		*lastlump = newlastlump; // okay, make the normal sprite set loading end there
@@ -633,7 +633,7 @@ static void R_LoadSkinSprites(UINT16 wadnum, UINT16 *lump, UINT16 *lastlump, ski
 
 	// load all sprite sets we are aware of... for normal stuff.
 	for (sprite2 = start_spr2; sprite2 < free_spr2; sprite2++)
-		R_AddSingleSpriteDef(spr2names[sprite2], &skin->sprites[sprite2], wadnum, *lump, *lastlump);
+		R_AddSingleSpriteDef(spr2names[sprite2], &skin->sprites[sprite2], wadnum, *lump, *lastlump, false);
 
 	if (skin->sprites[0].numframes == 0)
 		CONS_Alert(CONS_ERROR, M_GetText("No frames found for sprite SPR2_%s\n"), spr2names[0]);
diff --git a/src/r_things.c b/src/r_things.c
index 76e68068757fb1d387ac0c296c260f014f15098e..c46d8162460e6ac4df025457910f1eae92634628 100644
--- a/src/r_things.c
+++ b/src/r_things.c
@@ -77,7 +77,7 @@ spriteinfo_t spriteinfo[NUMSPRITES];
 spritedef_t *sprites;
 size_t numsprites;
 
-static spriteframe_t sprtemp[64];
+static spriteframe_t sprtemp[MAXFRAMENUM];
 static size_t maxframe;
 static const char *spritename;
 
@@ -116,6 +116,14 @@ static INT32 drawsegs_xrange_count = 0;
 //
 // ==========================================================================
 
+spritenum_t R_GetSpriteNumByName(const char *name)
+{
+	for (spritenum_t i = 0; i < NUMSPRITES; i++)
+		if (!strcmp(name, sprnames[i]))
+			return i;
+	return NUMSPRITES;
+}
+
 //
 //
 //
@@ -128,10 +136,14 @@ static void R_InstallSpriteLump(UINT16 wad,            // graphics patch
 {
 	char cn = R_Frame2Char(frame), cr = R_Rotation2Char(rotation); // for debugging
 
+	char framedescription[256];
+	if (cn != '\xFF')
+		sprintf(framedescription, "%s frame %d (%c)", spritename, frame, cn);
+	else
+		sprintf(framedescription, "%s frame %d", spritename, frame);
+
 	INT32 r;
-	lumpnum_t lumppat = wad;
-	lumppat <<= 16;
-	lumppat += lump;
+	lumpnum_t lumppat = (wad << 16) + lump;
 
 	if (maxframe ==(size_t)-1 || frame > maxframe)
 		maxframe = frame;
@@ -147,9 +159,9 @@ static void R_InstallSpriteLump(UINT16 wad,            // graphics patch
 	{
 		// the lump should be used for all rotations
 		if (sprtemp[frame].rotate == SRF_SINGLE)
-			CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s frame %c has multiple rot = 0 lump\n", spritename, cn);
+			CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s has multiple rot = 0 lump\n", framedescription);
 		else if (sprtemp[frame].rotate != SRF_NONE) // Let's bundle 1-8/16 and L/R rotations into one debug message.
-			CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s frame %c has rotations and a rot = 0 lump\n", spritename, cn);
+			CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s has rotations and a rot = 0 lump\n", framedescription);
 
 		sprtemp[frame].rotate = SRF_SINGLE;
 		for (r = 0; r < 16; r++)
@@ -169,15 +181,15 @@ static void R_InstallSpriteLump(UINT16 wad,            // graphics patch
 		if (sprtemp[frame].rotate == SRF_NONE)
 			sprtemp[frame].rotate = SRF_SINGLE;
 		else if (sprtemp[frame].rotate == SRF_SINGLE)
-			CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s frame %c has L/R rotations and a rot = 0 lump\n", spritename, cn);
+			CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s has L/R rotations and a rot = 0 lump\n", framedescription);
 		else if (sprtemp[frame].rotate == SRF_3D)
-			CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s frame %c has both L/R and 1-8 rotations\n", spritename, cn);
+			CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s has both L/R and 1-8 rotations\n", framedescription);
 		else if (sprtemp[frame].rotate == SRF_3DGE)
-			CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s frame %c has both L/R and 1-G rotations\n", spritename, cn);
+			CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s has both L/R and 1-G rotations\n", framedescription);
 		else if ((sprtemp[frame].rotate & SRF_LEFT) && (rotation == ROT_L))
-			CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s frame %c has multiple L rotations\n", spritename, cn);
+			CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s has multiple L rotations\n", framedescription);
 		else if ((sprtemp[frame].rotate & SRF_RIGHT) && (rotation == ROT_R))
-			CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s frame %c has multiple R rotations\n", spritename, cn);
+			CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s has multiple R rotations\n", framedescription);
 
 		sprtemp[frame].rotate |= ((rotation == ROT_R) ? SRF_RIGHT : SRF_LEFT);
 		if ((sprtemp[frame].rotate & SRF_2D) == SRF_2D)
@@ -204,9 +216,9 @@ static void R_InstallSpriteLump(UINT16 wad,            // graphics patch
 	if (sprtemp[frame].rotate == SRF_NONE)
 		sprtemp[frame].rotate = SRF_SINGLE;
 	else if (sprtemp[frame].rotate == SRF_SINGLE)
-		CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s frame %c has 1-8/G rotations and a rot = 0 lump\n", spritename, cn);
+		CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s has 1-8/G rotations and a rot = 0 lump\n", framedescription);
 	else if (sprtemp[frame].rotate & SRF_2D)
-		CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s frame %c has both L/R and 1-8/G rotations\n", spritename, cn);
+		CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s has both L/R and 1-8/G rotations\n", framedescription);
 
 	// make 0 based
 	rotation--;
@@ -226,7 +238,12 @@ static void R_InstallSpriteLump(UINT16 wad,            // graphics patch
 	}
 
 	if (sprtemp[frame].lumppat[rotation] != LUMPERROR)
-		CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s: %c%c has two lumps mapped to it\n", spritename, cn, cr);
+	{
+		if (cn != '\xFF')
+			CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s: %d_%c (%c%c) has two lumps mapped to it\n", spritename, frame, cr, cn, cr);
+		else
+			CONS_Debug(DBG_SETUP, "R_InitSprites: Sprite %s: %d_%c has two lumps mapped to it\n", spritename, frame, cr);
+	}
 
 	// lumppat & lumpid are the same for original Doom, but different
 	// when using sprites in pwad : the lumppat points the new graphics
@@ -238,24 +255,201 @@ static void R_InstallSpriteLump(UINT16 wad,            // graphics patch
 		sprtemp[frame].flip &= ~(1<<rotation);
 }
 
+static boolean GetFramesAndRotationsFromShortLumpName(
+	const char *name,
+	INT32 *ret_frame,
+	UINT8 *ret_rotation,
+	INT32 *ret_frame2,
+	UINT8 *ret_rotation2
+)
+{
+	size_t namelen = strlen(name);
+
+	if (namelen != 6 && namelen != 8)
+		return false;
+
+	*ret_frame = R_Char2Frame(name[4]);
+	*ret_rotation = R_Char2Rotation(name[5]);
+	if (*ret_frame >= 64 || *ret_rotation == 255)
+		return false;
+
+	if (namelen == 8)
+	{
+		*ret_frame2 = R_Char2Frame(name[6]);
+		*ret_rotation2 = R_Char2Rotation(name[7]);
+		if (*ret_frame2 >= 64 || *ret_rotation2 == 255)
+			return false;
+	}
+	else
+	{
+		*ret_frame2 = -1;
+		*ret_rotation2 = 255;
+	}
+
+	return true;
+}
+
+static boolean GetSingleFrameAndRotation(
+	const char *name,
+	size_t len,
+	INT32 *ret_frame,
+	UINT8 *ret_rotation
+)
+{
+	const char *underscore = strchr(name, '_');
+
+	// Found but past the part of the name we are parsing
+	if ((size_t)(underscore - name) >= len)
+		underscore = NULL;
+
+	size_t framelen = underscore ? (size_t)(underscore - name) : len;
+	if (framelen < 1 || framelen > 4)
+		return false;
+
+	char framepart[4 + 1]; // Max 9999
+	strlcpy(framepart, name, framelen + 1);
+
+	for (size_t i = 0; i < framelen; i++)
+		if (!isdigit(framepart[i]))
+			return false;
+
+	*ret_frame = atoi(framepart);
+	*ret_rotation = underscore ? R_Char2Rotation(*(underscore + 1)) : 0;
+	if (*ret_frame >= MAXFRAMENUM || *ret_rotation == 255)
+		return false;
+
+	return true;
+}
+
+static boolean GetFramesAndRotationsFromLongLumpName(
+	const char *name,
+	INT32 *ret_frame,
+	UINT8 *ret_rotation,
+	INT32 *ret_frame2,
+	UINT8 *ret_rotation2
+)
+{
+	const char *plus = strchr(name, '+');
+
+	if (plus)
+	{
+		size_t len1 = plus - name;
+
+		if (!GetSingleFrameAndRotation(name, len1, ret_frame, ret_rotation))
+			return false;
+		if (!GetSingleFrameAndRotation(plus + 1, strlen(name) - len1 - 1, ret_frame2, ret_rotation2))
+			return false;
+	}
+	else
+	{
+		if (!GetSingleFrameAndRotation(name, strlen(name), ret_frame, ret_rotation))
+			return false;
+
+		*ret_frame2 = -1;
+		*ret_rotation2 = 255;
+	}
+
+	return true;
+}
+
+static UINT8 GetOppositeRotation(UINT8 rotation, UINT8 flags)
+{
+	if (flags & ~SRF_3DMASK)
+		I_Error("GetOppositeRotation: rotation type not supported");
+
+	UINT8 numrotations = (flags == SRF_3D) ? 8 : 16;
+	return (rotation == 1) ? 1 : numrotations + 2 - rotation;
+}
+
+static void MirrorMissingRotations(void)
+{
+	for (UINT32 framenum = 0; framenum < maxframe; framenum++)
+	{
+		spriteframe_t *frame = &sprtemp[framenum];
+
+		if (frame->rotate == SRF_NONE || !(frame->rotate & SRF_3DMASK))
+			continue;
+
+		UINT8 numrotations = frame->rotate == SRF_3D ? 8 : 16;
+
+		for (UINT8 rotation = 1; rotation <= numrotations; rotation++)
+		{
+			if (frame->lumppat[rotation - 1] != LUMPERROR)
+				continue;
+
+			UINT8 baserotation = GetOppositeRotation(rotation, frame->rotate);
+			UINT32 lumpnum = frame->lumppat[baserotation - 1];
+			R_InstallSpriteLump(WADFILENUM(lumpnum), LUMPNUM(lumpnum), frame->lumpid[baserotation], framenum, rotation, 1);
+		}
+	}
+}
+
+// Some checks to help development
+static void CheckFrame(const char *sprname)
+{
+	for (UINT32 frame = 0; frame < maxframe; frame++)
+	{
+		spriteframe_t *spriteframe = &sprtemp[frame];
+
+		char framedescription[256];
+		if (frame < 64)
+			sprintf(framedescription, "%s frame %d (%c)", sprname, frame, R_Frame2Char(frame));
+		else
+			sprintf(framedescription, "%s frame %d", sprname, frame);
+
+		switch (spriteframe->rotate)
+		{
+		case SRF_NONE:
+			// no rotations were found for that frame at all
+			I_Error("R_AddSingleSpriteDef: No patches found for %s", framedescription);
+			break;
+
+		case SRF_SINGLE:
+			// only the first rotation is needed
+			break;
+
+		case SRF_2D: // both Left and Right rotations
+			// we test to see whether the left and right slots are present
+			if ((spriteframe->lumppat[2] == LUMPERROR) || (spriteframe->lumppat[6] == LUMPERROR))
+				I_Error("R_AddSingleSpriteDef: Sprite %s is missing rotations (L-R mode)",
+				framedescription);
+			break;
+
+		default:
+			{
+				// must have all 8/16 frames
+				UINT8 rotation = ((spriteframe->rotate & SRF_3DGE) ? 16 : 8);
+				while (rotation--)
+				{
+					// we test the patch lump, or the id lump whatever
+					// if it was not loaded the two are LUMPERROR
+					if (spriteframe->lumppat[rotation] == LUMPERROR)
+						I_Error("R_AddSingleSpriteDef: Sprite %s is missing rotations (1-%c mode)",
+								framedescription, ((spriteframe->rotate & SRF_3DGE) ? 'G' : '8'));
+				}
+			}
+			break;
+		}
+	}
+}
+
 // Install a single sprite, given its identifying name (4 chars)
 //
 // (originally part of R_AddSpriteDefs)
 //
-// Pass: name of sprite : 4 chars
+// Pass: name of sprite
 //       spritedef_t
 //       wadnum         : wad number, indexes wadfiles[], where patches
 //                        for frames are found
 //       startlump      : first lump to search for sprite frames
 //       endlump        : AFTER the last lump to search
+//       longname       : whether to use long sprite names or 4-char names
 //
 // Returns true if the sprite was succesfully added
 //
-boolean R_AddSingleSpriteDef(const char *sprname, spritedef_t *spritedef, UINT16 wadnum, UINT16 startlump, UINT16 endlump)
+boolean R_AddSingleSpriteDef(const char *sprname, spritedef_t *spritedef, UINT16 wadnum, UINT16 startlump, UINT16 endlump, boolean longname)
 {
 	UINT16 l;
-	UINT8 frame;
-	UINT8 rotation;
 	lumpinfo_t *lumpinfo;
 	UINT16 numadded = 0;
 
@@ -282,15 +476,23 @@ boolean R_AddSingleSpriteDef(const char *sprname, spritedef_t *spritedef, UINT16
 
 	for (l = startlump; l < endlump; l++)
 	{
-		if (memcmp(lumpinfo[l].name,sprname,4)==0)
+		if (longname && W_IsLumpFolder(wadnum, l))
+			I_Error("R_AddSingleSpriteDef: all frame lumps for a sprite should be contained inside a single folder\n");
+
+		// For long sprites, the startlump-endlump range only includes
+		// relevant lumps, so no check needed in that case
+		if (longname || (strlen(sprname) == 4 && !memcmp(lumpinfo[l].name, sprname, 4)))
 		{
 			INT16 width, height;
 			INT16 topoffset, leftoffset;
+			INT32 frame, frame2;
+			UINT8 rotation, rotation2;
 
-			frame = R_Char2Frame(lumpinfo[l].name[4]);
-			rotation = R_Char2Rotation(lumpinfo[l].name[5]);
+			boolean good = longname ?
+				GetFramesAndRotationsFromLongLumpName(lumpinfo[l].longname, &frame, &rotation, &frame2, &rotation2) :
+				GetFramesAndRotationsFromShortLumpName(lumpinfo[l].name, &frame, &rotation, &frame2, &rotation2);
 
-			if (frame >= 64 || rotation == 255) // Give an actual NAME error -_-...
+			if (!good) // Give an actual NAME error -_-...
 			{
 				CONS_Alert(CONS_WARNING, M_GetText("Bad sprite name: %s\n"), W_CheckNameForNumPwad(wadnum,l));
 				continue;
@@ -322,19 +524,8 @@ boolean R_AddSingleSpriteDef(const char *sprname, spritedef_t *spritedef, UINT16
 			//----------------------------------------------------
 
 			R_InstallSpriteLump(wadnum, l, numspritelumps, frame, rotation, 0);
-
-			if (lumpinfo[l].name[6])
-			{
-				frame = R_Char2Frame(lumpinfo[l].name[6]);
-				rotation = R_Char2Rotation(lumpinfo[l].name[7]);
-
-				if (frame >= 64 || rotation == 255) // Give an actual NAME error -_-...
-				{
-					CONS_Alert(CONS_WARNING, M_GetText("Bad sprite name: %s\n"), W_CheckNameForNumPwad(wadnum,l));
-					continue;
-				}
-				R_InstallSpriteLump(wadnum, l, numspritelumps, frame, rotation, 1);
-			}
+			if (frame2 != -1)
+				R_InstallSpriteLump(wadnum, l, numspritelumps, frame2, rotation2, 1);
 
 			if (++numspritelumps >= max_spritelumps)
 			{
@@ -374,41 +565,10 @@ boolean R_AddSingleSpriteDef(const char *sprname, spritedef_t *spritedef, UINT16
 
 	maxframe++;
 
-	//
-	//  some checks to help development
-	//
-	for (frame = 0; frame < maxframe; frame++)
-	{
-		switch (sprtemp[frame].rotate)
-		{
-			case SRF_NONE:
-			// no rotations were found for that frame at all
-			I_Error("R_AddSingleSpriteDef: No patches found for %.4s frame %c", sprname, R_Frame2Char(frame));
-			break;
-
-			case SRF_SINGLE:
-			// only the first rotation is needed
-			break;
-
-			case SRF_2D: // both Left and Right rotations
-			// we test to see whether the left and right slots are present
-			if ((sprtemp[frame].lumppat[2] == LUMPERROR) || (sprtemp[frame].lumppat[6] == LUMPERROR))
-				I_Error("R_AddSingleSpriteDef: Sprite %.4s frame %c is missing rotations (L-R mode)",
-				sprname, R_Frame2Char(frame));
-			break;
+	if (longname)
+		MirrorMissingRotations();
 
-			default:
-			// must have all 8/16 frames
-				rotation = ((sprtemp[frame].rotate & SRF_3DGE) ? 16 : 8);
-				while (rotation--)
-				// we test the patch lump, or the id lump whatever
-				// if it was not loaded the two are LUMPERROR
-				if (sprtemp[frame].lumppat[rotation] == LUMPERROR)
-					I_Error("R_AddSingleSpriteDef: Sprite %.4s frame %c is missing rotations (1-%c mode)",
-					        sprname, R_Frame2Char(frame), ((sprtemp[frame].rotate & SRF_3DGE) ? 'G' : '8'));
-			break;
-		}
-	}
+	CheckFrame(sprname);
 
 	// allocate space for the frames present and copy sprtemp to it
 	if (spritedef->numframes &&             // has been allocated
@@ -429,14 +589,10 @@ boolean R_AddSingleSpriteDef(const char *sprname, spritedef_t *spritedef, UINT16
 	return true;
 }
 
-//
-// Search for sprites replacements in a wad whose names are in namelist
-//
-void R_AddSpriteDefs(UINT16 wadnum)
+static void AddShortSpriteDefs(UINT16 wadnum, size_t *ptr_spritesadded, size_t *ptr_framesadded)
 {
-	size_t i, addsprites = 0;
+	size_t i;
 	UINT16 start, end;
-	char wadname[MAX_WADPATH];
 
 	// Find the sprites section in this resource file.
 	switch (wadfiles[wadnum]->type)
@@ -474,27 +630,90 @@ void R_AddSpriteDefs(UINT16 wadnum)
 		return;
 	}
 
-
 	//
 	// scan through lumps, for each sprite, find all the sprite frames
 	//
 	for (i = 0; i < numsprites; i++)
 	{
-		if (sprnames[i][4] && wadnum >= (UINT16)sprnames[i][4])
-			continue;
-
-		if (R_AddSingleSpriteDef(sprnames[i], &sprites[i], wadnum, start, end))
+		if (R_AddSingleSpriteDef(sprnames[i], &sprites[i], wadnum, start, end, false))
 		{
 			// if a new sprite was added (not just replaced)
-			addsprites++;
+			(*ptr_spritesadded)++;
 #ifndef ZDEBUG
 			CONS_Debug(DBG_SETUP, "sprite %s set in pwad %d\n", sprnames[i], wadnum);
 #endif
 		}
 	}
 
-	nameonly(strcpy(wadname, wadfiles[wadnum]->filename));
-	CONS_Printf(M_GetText("%s added %d frames in %s sprites\n"), wadname, end-start, sizeu1(addsprites));
+	*ptr_framesadded += end - start;
+}
+
+static void AddLongSpriteDefs(UINT16 wadnum, size_t *ptr_spritesadded, size_t *ptr_framesadded)
+{
+	if (!W_FileHasFolders(wadfiles[wadnum]))
+		return;
+
+	UINT16 start = W_CheckNumForFolderStartPK3("LongSprites/", wadnum, 0);
+	UINT16 end = W_CheckNumForFolderEndPK3("LongSprites/", wadnum, start);
+
+	if (start == INT16_MAX || end == INT16_MAX || start >= end)
+		return;
+
+	size_t lumpnum = start;
+
+	while (lumpnum < end)
+	{
+		if (W_IsLumpFolder(wadnum, lumpnum))
+		{
+			lumpnum++;
+			continue;
+		}
+
+		UINT16 folderstart, folderend;
+		char *folderpath = W_GetLumpFolderPathPK3(wadnum, lumpnum);
+		folderstart = lumpnum;
+		folderend = W_CheckNumForFolderEndPK3(folderpath, wadnum, lumpnum);
+		Z_Free(folderpath);
+
+		spritenum_t sprnum;
+		char *sprname = W_GetLumpFolderNamePK3(wadnum, lumpnum);
+		strupr(sprname);
+		sprnum = R_GetSpriteNumByName(sprname);
+
+		if (sprnum != NUMSPRITES && R_AddSingleSpriteDef(sprname, &sprites[sprnum], wadnum, folderstart, folderend, true))
+		{
+			// A new sprite was added (not just replaced)
+			(*ptr_spritesadded)++;
+#ifndef ZDEBUG
+			CONS_Debug(DBG_SETUP, "long sprite %s set in pwad %d\n", sprname, wadnum);
+#endif
+		}
+
+		Z_Free(sprname);
+
+		lumpnum = folderend;
+	}
+
+	*ptr_framesadded += end - start;
+}
+
+//
+// Search for sprites replacements in a wad whose names are in namelist
+//
+void R_AddSpriteDefs(UINT16 wadnum)
+{
+	char wadname[MAX_WADPATH];
+	size_t spritesadded = 0;
+	size_t framesadded = 0;
+
+	AddShortSpriteDefs(wadnum, &spritesadded, &framesadded);
+	AddLongSpriteDefs(wadnum, &spritesadded, &framesadded);
+
+	if (spritesadded || framesadded)
+	{
+		nameonly(strcpy(wadname, wadfiles[wadnum]->filename));
+		CONS_Printf(M_GetText("%s added %s frames in %s sprites\n"), wadname, sizeu1(framesadded), sizeu2(spritesadded));
+	}
 }
 
 //
diff --git a/src/r_things.h b/src/r_things.h
index f68d75a837ef698bcb98fc4e6dc568f97bf8881a..3daf55c4235bc753aeb5f1c897856e6d9303338c 100644
--- a/src/r_things.h
+++ b/src/r_things.h
@@ -27,7 +27,9 @@
 
 #define FEETADJUST (4<<FRACBITS) // R_AddSingleSpriteDef
 
-boolean R_AddSingleSpriteDef(const char *sprname, spritedef_t *spritedef, UINT16 wadnum, UINT16 startlump, UINT16 endlump);
+spritenum_t R_GetSpriteNumByName(const char *name);
+
+boolean R_AddSingleSpriteDef(const char *sprname, spritedef_t *spritedef, UINT16 wadnum, UINT16 startlump, UINT16 endlump, boolean longname);
 
 //faB: find sprites in wadfile, replace existing, add new ones
 //     (only sprites from namelist are added or replaced)
diff --git a/src/s_sound.c b/src/s_sound.c
index aa049899ff602cf6a1f7af4c287d8f3673bf5597..5155b90e8abe03901670bd8e5f38b29a7cdd508c 100644
--- a/src/s_sound.c
+++ b/src/s_sound.c
@@ -2494,11 +2494,11 @@ static void Command_Tunes_f(void)
 		track = (UINT16)atoi(COM_Argv(2))-1;
 
 	strncpy(mapmusname, tunearg, 7);
+	mapmusname[6] = 0;
 
 	if (argc > 4)
 		position = (UINT32)atoi(COM_Argv(4));
 
-	mapmusname[6] = 0;
 	mapmusflags = (track & MUSIC_TRACKMASK);
 	mapmusposition = position;
 
diff --git a/src/sdl/CMakeLists.txt b/src/sdl/CMakeLists.txt
index 5aca04d120c39287eec5c2097aa6375e52eb27fb..ee48fa2b154568889c50d4e0a6c8d97c5c2a7bf0 100644
--- a/src/sdl/CMakeLists.txt
+++ b/src/sdl/CMakeLists.txt
@@ -1,7 +1,6 @@
 # Declare SDL2 interface sources
 
 target_sources(SRB2SDL2 PRIVATE
-	mixer_sound.c
 	ogl_sdl.c
 	i_threads.c
 	i_net.c
@@ -13,6 +12,161 @@ target_sources(SRB2SDL2 PRIVATE
 	hwsym_sdl.c
 )
 
+# Compatibility flag with later versions of GCC
+# We should really fix our code to not need this
+if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
+    target_compile_options(SRB2SDL2 PRIVATE -mno-ms-bitfields)
+endif()
+
+# Yes we know we use insecure CRT functions...
+if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "MSVC")
+    target_compile_definitions(SRB2SDL2 PRIVATE -D_CRT_SECURE_NO_WARNINGS)
+endif()
+
+# Compiler warnings configuration
+target_compile_options(SRB2SDL2 PRIVATE
+    # Using generator expressions to handle per-language compile options
+
+    # C, GNU
+    # This is a direct translation from versions.mk
+    $<$<AND:$<COMPILE_LANGUAGE:C>,$<C_COMPILER_ID:GNU>>:
+        -Wall
+        -Wno-trigraphs
+        -W # Was controlled by RELAXWARNINGS
+        -pedantic
+        -Wpedantic
+        -Wfloat-equal
+        -Wundef
+        -Wpointer-arith
+        -Wbad-function-cast
+        -Wcast-qual
+        -Wcast-align # Was controlled by NOCASTALIGNWARN
+        -Wwrite-strings
+        -Wsign-compare
+        -Wmissing-prototypes
+        -Wmissing-declarations
+        -Wmissing-noreturn
+        -Winline
+        -Wformat-y2k
+        -Wformat-security
+
+        $<$<VERSION_LESS:$<C_COMPILER_VERSION>,2.9.5>:
+            -Wno-div-by-zero
+            -Wendif-labels
+            -Wdisabled-optimization
+        >
+
+        $<$<VERSION_GREATER_EQUAL:$<C_COMPILER_VERSION>,4.0.0>:
+            -Wold-style-definition
+            -Wmissing-field-initializers
+        >
+
+        $<$<VERSION_GREATER_EQUAL:$<C_COMPILER_VERSION>,4.1.0>:
+            -Wshadow
+        >
+
+        $<$<VERSION_GREATER_EQUAL:$<C_COMPILER_VERSION>,4.3.0>:
+            -funit-at-a-time
+            -Wlogical-op
+        >
+
+        $<$<VERSION_GREATER_EQUAL:$<C_COMPILER_VERSION>,4.5.0>:
+            -Wlogical-op
+            -Wno-error=array-bounds
+        >
+
+        $<$<VERSION_GREATER_EQUAL:$<C_COMPILER_VERSION>,4.6.0>:
+            -Wno-suggest-attribute=noreturn
+            -Wno-error=suggest-attribute=noreturn
+            -Werror=vla
+        >
+
+        $<$<VERSION_GREATER_EQUAL:$<C_COMPILER_VERSION>,5.4.0>:
+            -Wno-logical-op
+            -Wno-error=logical-op
+        >
+
+        $<$<VERSION_GREATER_EQUAL:$<C_COMPILER_VERSION>,6.1.0>:
+            -Wno-tautological-compare
+            -Wno-error=tautological-compare
+        >
+
+        $<$<VERSION_GREATER_EQUAL:$<C_COMPILER_VERSION>,7.1.0>:
+            -Wno-error=format-overflow=2
+            -Wimplicit-fallthrough=4
+        >
+
+        $<$<VERSION_GREATER_EQUAL:$<C_COMPILER_VERSION>,8.1.0>:
+            -Wno-error=format-overflow
+            -Wno-error=stringop-truncation
+            -Wno-error=stringop-overflow
+            -Wno-format-overflow
+            -Wno-stringop-truncation
+            -Wno-stringop-overflow
+            -Wno-error=multistatement-macros
+        >
+
+        $<$<VERSION_GREATER_EQUAL:$<C_COMPILER_VERSION>,9.1.0>:
+            -Wno-error=address-of-packed-member
+        >
+    >
+
+    # C, Clang and Apple Clang
+    $<$<AND:$<COMPILE_LANGUAGE:C>,$<OR:$<C_COMPILER_ID:AppleClang>,$<C_COMPILER_ID:Clang>>>:
+        -Wall
+        -Wno-absolute-value
+        -Wno-trigraphs
+        -Wno-error=non-literal-null-conversion
+        -Wno-error=constant-conversion
+        -Wno-unused-but-set-variable
+        -Wno-error=unused-but-set-variable
+        -Wno-shorten-64-to-32
+    >
+
+    # C, MSVC
+    $<$<AND:$<COMPILE_LANGUAGE:C>,$<C_COMPILER_ID:MSVC>>:
+        # All warnings at and before Visual Studio 2019 RTM
+        # https://learn.microsoft.com/en-us/cpp/error-messages/compiler-warnings/compiler-warnings-by-compiler-version?view=msvc-170
+        /Wv:19.20.27004.0
+    >
+
+    # C++, GNU, Clang and Apple Clang
+    $<$<AND:$<COMPILE_LANGUAGE:CXX>,$<OR:$<C_COMPILER_ID:GNU>,$<C_COMPILER_ID:AppleClang>,$<C_COMPILER_ID:Clang>>>:
+        -Wall
+        -Wno-unused-function
+        -Wno-unused-but-set-variable
+        -Wno-unused-private-field
+    >
+
+    # C++, MSVC
+    $<$<AND:$<COMPILE_LANGUAGE:CXX>,$<C_COMPILER_ID:MSVC>>:
+        /Wv:19.20.27004.0
+    >
+
+    # GNU
+    $<$<C_COMPILER_ID:GNU>:
+        -fmax-errors=5
+    >
+)
+if(SRB2_CONFIG_ERRORMODE)
+    target_compile_options(SRB2SDL2 PRIVATE
+        $<$<OR:$<C_COMPILER_ID:GNU>,$<C_COMPILER_ID:AppleClang>,$<C_COMPILER_ID:Clang>>:
+            -Werror
+        >
+
+        $<$<C_COMPILER_ID:MSVC>:
+            /WX
+        >
+    )
+endif()
+
+# Link warnings configuration
+target_link_options(SRB2SDL2 PRIVATE
+    $<$<C_COMPILER_ID:GNU>:
+        # -Wl,--as-needed   - Was controlled by NOLDWARNING
+    >
+)
+
 if("${CMAKE_SYSTEM_NAME}" MATCHES Windows)
 	target_sources(SRB2SDL2 PRIVATE
 		../win32/win_dbg.c
@@ -62,12 +216,6 @@ if("${CMAKE_SYSTEM_NAME}" MATCHES Windows)
 	target_link_libraries(SRB2SDL2 PRIVATE SDL2::SDL2main)
 endif()
 
-if(NOT "${SRB2_CONFIG_SYSTEM_LIBRARIES}" AND NOT "${SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES}")
-	target_link_libraries(SRB2SDL2 PRIVATE SDL2::SDL2-static SDL2_mixer::SDL2_mixer-static)
-else()
-	target_link_libraries(SRB2SDL2 PRIVATE SDL2::SDL2 SDL2_mixer::SDL2_mixer)
-endif()
-
 if("${CMAKE_SYSTEM_NAME}" MATCHES Linux)
 	target_link_libraries(SRB2SDL2 PRIVATE m rt)
 endif()
@@ -81,8 +229,84 @@ if("${CMAKE_SYSTEM_NAME}" MATCHES Windows)
 	)
 endif()
 
-target_compile_definitions(SRB2SDL2 PRIVATE -DHAVE_MIXER -DSOUND=SOUND_MIXER)
+find_package(SDL2 CONFIG REQUIRED)
+find_package(SDL2 REQUIRED)
+if(TARGET SDL2main)
+	target_link_libraries(SRB2SDL2 PRIVATE SDL2main)
+endif()
 target_compile_definitions(SRB2SDL2 PRIVATE -DDIRECTFULLSCREEN -DHAVE_SDL)
+target_include_directories(SRB2SDL2 PRIVATE ${SDL2_INCLUDE_DIR})
+
+find_package(SDL2_mixer_ext CONFIG QUIET)
+find_package(SDL2_mixer_ext QUIET)
+if(TARGET SDL2_mixer_ext::SDL2_mixer_ext OR TARGET SDL2_mixer_ext::SDL2_mixer_ext_Static OR TARGET SDL2_mixer_ext OR TARGET SDL2_mixer_ext_Static)
+	if(NOT TARGET SDL2_mixer_ext::SDL2_mixer_ext_Static AND TARGET SDL2_mixer_ext_Static)
+	add_library(SDL2_mixer_ext::SDL2_mixer_ext_Static ALIAS SDL2_mixer_ext_Static)
+	endif()
+	if(NOT TARGET SDL2_mixer_ext::SDL2_mixer_ext AND TARGET SDL2_mixer_ext)
+	add_library(SDL2_mixer_ext::SDL2_mixer_ext ALIAS SDL2_mixer_ext)
+	endif()
+	if(TARGET SDL2_mixer_ext::SDL2_mixer_ext OR TARGET SDL2_mixer_ext::SDL2_mixer_ext_Static)
+		if(TARGET SDL2_mixer_ext::SDL2_mixer_ext_Static)
+			target_link_libraries(SRB2SDL2 PRIVATE SDL2_mixer_ext::SDL2_mixer_ext_Static)
+		else()
+			target_link_libraries(SRB2SDL2 PRIVATE SDL2_mixer_ext::SDL2_mixer_ext)
+		endif()
+	target_compile_definitions(SRB2SDL2 PRIVATE -DHAVE_MIXER -DHAVE_MIXERX -DSOUND=SOUND_MIXER)
+	endif()
+endif()
+
+if(TARGET SDL2_mixer_ext::SDL2_mixer_ext OR TARGET SDL2_mixer_ext::SDL2_mixer_ext_Static)
+	message(STATUS "SDL2_mixer_ext found, skipping SDL2_mixer")
+else()
+	message(STATUS "SDL2_mixer_ext not found, going to try SDL2_mixer")
+	find_package(SDL2_mixer CONFIG QUIET)
+	find_package(SDL2_mixer QUIET)
+	if(TARGET SDL2_mixer::SDL2_mixer OR TARGET SDL2_mixer::SDL2_mixer-static OR TARGET SDL2_mixer OR TARGET SDL2_mixer_Static)
+		if(NOT TARGET SDL2_mixer::SDL2_mixer-static AND TARGET SDL2_mixer_Static)
+		add_library(SDL2_mixer::SDL2_mixer-static ALIAS SDL2_mixer_Static)
+		endif()
+		if(NOT TARGET SDL2_mixer::SDL2_mixer AND TARGET SDL2_mixer)
+		add_library(SDL2_mixer::SDL2_mixer ALIAS SDL2_mixer)
+		endif()
+		if(TARGET SDL2_mixer::SDL2_mixer OR TARGET SDL2_mixer::SDL2_mixer-static)
+			if(TARGET SDL2_mixer::SDL2_mixer-static)
+				target_link_libraries(SRB2SDL2 PRIVATE SDL2_mixer::SDL2_mixer-static)
+			else()
+				target_link_libraries(SRB2SDL2 PRIVATE SDL2_mixer::SDL2_mixer)
+			endif()
+		target_compile_definitions(SRB2SDL2 PRIVATE -DHAVE_MIXER -DSOUND=SOUND_MIXER)
+		endif()
+	endif()
+endif()
+
+if(TARGET SDL2_mixer_ext::SDL2_mixer_ext OR TARGET SDL2_mixer_ext::SDL2_mixer_ext_Static OR TARGET SDL2_mixer::SDL2_mixer OR TARGET SDL2_mixer::SDL2_mixer-static)
+	target_sources(SRB2SDL2 PRIVATE mixer_sound.c)
+	target_link_libraries(SRB2SDL2 PRIVATE SDL2::SDL2)
+else()
+	target_sources(SRB2SDL2 PRIVATE sdl_sound.c)
+	target_link_libraries(SRB2SDL2 PRIVATE SDL2::SDL2)
+endif()
+
+if(TARGET SDL2::SDL2)
+	message(STATUS "SDL2 Found")
+else()
+	message(STATUS "no SDL2 Found")
+endif()
+
+if(TARGET SDL2::SDL2main)
+	message(STATUS "SDL2main Found")
+else()
+	message(STATUS "No SDL2main Found")
+endif()
+
+if(TARGET SDL2_mixer_ext::SDL2_mixer_ext OR TARGET SDL2_mixer_ext::SDL2_mixer_ext_Static)
+	message(STATUS "SDL2_mixer_ext Found")
+elseif(TARGET SDL2_mixer::SDL2_mixer OR TARGET SDL2_mixer::SDL2_mixer-static)
+	message(STATUS "SDL2_mixer found")
+else()
+	message(STATUS "no SDL2_mixer_ext or SDL2_mixer Found")
+endif()
 
 #### Installation ####
 if("${CMAKE_SYSTEM_NAME}" MATCHES Darwin)
diff --git a/src/sdl/i_system.c b/src/sdl/i_system.c
index c8af1b1910ca3bf52cfeb841c151b3fd5c0f368c..bfba6ac5928f97f84b7ab14ea78419fa50e16ffe 100644
--- a/src/sdl/i_system.c
+++ b/src/sdl/i_system.c
@@ -2316,7 +2316,7 @@ void I_SleepDuration(precise_t duration)
 	int status;
 	do status = clock_nanosleep(CLOCK_MONOTONIC, 0, &ts, &ts);
 	while (status == EINTR);
-#else
+#elif defined (MIN_SLEEP_DURATION_MS)
 	UINT64 precision = I_GetPrecisePrecision();
 	INT32 sleepvalue = cv_sleep.value;
 	UINT64 delaygranularity;
diff --git a/src/tests/CMakeLists.txt b/src/tests/CMakeLists.txt
deleted file mode 100644
index 28c4ce492f2d8b4e7590e3ac10f9ce6a95d98a0f..0000000000000000000000000000000000000000
--- a/src/tests/CMakeLists.txt
+++ /dev/null
@@ -1,3 +0,0 @@
-target_sources(srb2tests PRIVATE
-	boolcompat.cpp
-)
diff --git a/src/tests/boolcompat.cpp b/src/tests/boolcompat.cpp
deleted file mode 100644
index fee40cd36f2bce34217a875024d6b41fe71adbd1..0000000000000000000000000000000000000000
--- a/src/tests/boolcompat.cpp
+++ /dev/null
@@ -1,8 +0,0 @@
-#include <catch2/catch_test_macros.hpp>
-
-#include "../doomtype.h"
-
-TEST_CASE("C++ bool is convertible to doomtype.h boolean") {
-	REQUIRE(static_cast<boolean>(true) == 1);
-	REQUIRE(static_cast<boolean>(false) == 0);
-}
diff --git a/src/w_wad.c b/src/w_wad.c
index 0666c4a600bcf20678f88539fb4055a0d5466992..78d26f9056c16e818d0384d1f91f2237d8b8024b 100644
--- a/src/w_wad.c
+++ b/src/w_wad.c
@@ -1349,6 +1349,47 @@ UINT16 W_CheckNumForFolderEndPK3(const char *name, UINT16 wad, UINT16 startlump)
 	return i;
 }
 
+char *W_GetLumpFolderPathPK3(UINT16 wad, UINT16 lump)
+{
+	const char *fullname = wadfiles[wad]->lumpinfo[lump].fullname;
+
+	const char *slash = strrchr(fullname, '/');
+	INT32 pathlen = slash ? slash - fullname : 0;
+
+	char *path = Z_Calloc(pathlen + 1, PU_STATIC, NULL);
+	strncpy(path, fullname, pathlen);
+
+	return path;
+}
+
+char *W_GetLumpFolderNamePK3(UINT16 wad, UINT16 lump)
+{
+	const char *fullname = wadfiles[wad]->lumpinfo[lump].fullname;
+	size_t start, end;
+
+	INT32 i = strlen(fullname);
+
+	i--;
+	while (i >= 0 && fullname[i] != '/')
+		i--;
+	if (i < 0)
+		return NULL;
+	end = i;
+
+	i--;
+	while (i >= 0 && fullname[i] != '/')
+		i--;
+	if (i < 0)
+		return NULL;
+	start = i + 1;
+
+	size_t namelen = end - start;
+	char *foldername = Z_Calloc(namelen + 1, PU_STATIC, NULL);
+	strncpy(foldername, fullname + start, namelen);
+
+	return foldername;
+}
+
 void W_GetFolderLumpsPwad(const char *name, UINT16 wad, UINT32 **list, UINT16 *list_capacity, UINT16 *numlumps)
 {
 	size_t name_length = strlen(name);
diff --git a/src/w_wad.h b/src/w_wad.h
index e043e4d62c82f061ce505c4ce6b6a2298d48a4ec..80e0e32fd585faaddcaf24dd8167e3f694d388f2 100644
--- a/src/w_wad.h
+++ b/src/w_wad.h
@@ -180,6 +180,8 @@ UINT16 W_CheckNumForMarkerStartPwad(const char *name, UINT16 wad, UINT16 startlu
 UINT16 W_CheckNumForFullNamePK3(const char *name, UINT16 wad, UINT16 startlump);
 UINT16 W_CheckNumForFolderStartPK3(const char *name, UINT16 wad, UINT16 startlump);
 UINT16 W_CheckNumForFolderEndPK3(const char *name, UINT16 wad, UINT16 startlump);
+char *W_GetLumpFolderPathPK3(UINT16 wad, UINT16 lump);
+char *W_GetLumpFolderNamePK3(UINT16 wad, UINT16 lump);
 
 void W_GetFolderLumpsPwad(const char *name, UINT16 wad, UINT32 **list, UINT16 *list_capacity, UINT16 *numlumps);
 void W_GetFolderLumps(const char *name, UINT32 **list, UINT16 *list_capacity, UINT16 *numlumps);
diff --git a/thirdparty/00-SDL-Mixer-X-2.6.0-DISABLE_INSTALL.patch b/thirdparty/00-SDL-Mixer-X-2.6.0-DISABLE_INSTALL.patch
new file mode 100644
index 0000000000000000000000000000000000000000..0e7f55f1b282300bbdb6d21a8abd67373fd45828
--- /dev/null
+++ b/thirdparty/00-SDL-Mixer-X-2.6.0-DISABLE_INSTALL.patch
@@ -0,0 +1,26 @@
+--- a/CMakeLists.txt	2023-11-22 22:42:53.000000000 -0500
++++ b/CMakeLists.txt	2024-02-15 18:46:57.852076200 -0500
+@@ -45,6 +45,7 @@
+ 
+     option(SDL_MIXER_X_STATIC   "Build static library of SDL Mixer X" ${SDL_MIXER_X_STATIC_ENABLED_BY_DEFAULT})
+     option(SDL_MIXER_X_SHARED   "Build shared library of SDL Mixer X" ${SDL_MIXER_X_SHARED_ENABLED_BY_DEFAULT})
++     option(SDL_MIXER_X_DISABLE_INSTALL   "Disable install of SDL Mixer X" OFF)
+ else()
+     set(SDL_MIXER_X_STATIC ON)
+     set(SDL_MIXER_X_SHARED OFF)
+@@ -475,6 +476,7 @@
+     add_subdirectory(examples)
+ endif()
+ 
++if(NOT SDL_MIXER_X_DISABLE_INSTALL)
+ if(SDL_MIXER_X_STATIC AND NOT BUILD_AS_VB6_BINDING)
+     install(TARGETS SDL2_mixer_ext_Static
+             EXPORT SDL2MixerExtStaticTargets
+@@ -500,6 +502,7 @@
+             NAMESPACE SDL2_mixer_ext::
+             DESTINATION "${CMAKE_INSTALL_LIBDIR}/cmake/SDL2_mixer_ext")
+ endif()
++endif()
+ 
+ 
+ if(BUILD_AS_VB6_BINDING)
diff --git a/thirdparty/CMakeLists.txt b/thirdparty/CMakeLists.txt
index 19aa22c9b7a17613910dbdc9f28717e16e604986..5114cbe2c81432173409cce5a113ea9305b5b23b 100644
--- a/thirdparty/CMakeLists.txt
+++ b/thirdparty/CMakeLists.txt
@@ -1,23 +1,2 @@
-macro(export)
-endmacro()
 
-if(SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES)
-	set(SRB2_INTERNAL_LIBRARY_TYPE SHARED)
-	set(NOT_SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES OFF)
-else()
-	set(SRB2_INTERNAL_LIBRARY_TYPE STATIC)
-	set(NOT_SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES ON)
-endif()
-
-if(NOT "${SRB2_CONFIG_SYSTEM_LIBRARIES}")
-	include("cpm-sdl2.cmake")
-	include("cpm-sdl2-mixer.cmake")
-	include("cpm-zlib.cmake")
-	include("cpm-png.cmake")
-	include("cpm-curl.cmake")
-	include("cpm-openmpt.cmake")
-endif()
-
-if("${SRB2_CONFIG_USE_GME}")
-	include("cpm-libgme.cmake")
-endif()
+include("Ccache.cmake")
diff --git a/thirdparty/Ccache.cmake b/thirdparty/Ccache.cmake
new file mode 100644
index 0000000000000000000000000000000000000000..6ca0d9fa0615d8cf091992ed84bec7b4fef09144
--- /dev/null
+++ b/thirdparty/Ccache.cmake
@@ -0,0 +1,15 @@
+# Enable CCache
+# (Set USE_CCACHE=ON to use, CCACHE_OPTIONS for options)
+if("${CMAKE_HOST_SYSTEM_NAME}" STREQUAL Windows)
+	option(USE_CCACHE "Enable ccache support" OFF)
+
+	if(USE_CCACHE)
+		find_program(CCACHE_TOOL_PATH ccache)
+		if(CCACHE_TOOL_PATH)
+			set(CMAKE_C_COMPILER_LAUNCHER ${CCACHE_TOOL_PATH} CACHE STRING "" FORCE)
+			set(CMAKE_CXX_COMPILER_LAUNCHER ${CCACHE_TOOL_PATH} CACHE STRING "" FORCE)
+		else()
+			message(WARNING "USE_CCACHE was set but ccache is not found (set CCACHE_TOOL_PATH)")
+		endif()
+	endif()
+endif()
\ No newline at end of file
diff --git a/thirdparty/cpm-libgme.cmake b/thirdparty/cpm-libgme.cmake
deleted file mode 100644
index f15bc3b31cb23ed7663ed950c14c1d6a0dc36567..0000000000000000000000000000000000000000
--- a/thirdparty/cpm-libgme.cmake
+++ /dev/null
@@ -1,16 +0,0 @@
-CPMAddPackage(
-	NAME libgme
-	VERSION 0.6.3
-	URL "https://bitbucket.org/mpyne/game-music-emu/get/e76bdc0cb916e79aa540290e6edd0c445879d3ba.zip"
-	EXCLUDE_FROM_ALL ON
-	OPTIONS
-		"BUILD_SHARED_LIBS ${SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES}"
-		"ENABLE_UBSAN OFF"
-		"GME_YM2612_EMU MAME"
-)
-
-if(libgme_ADDED)
-	target_compile_features(gme PRIVATE cxx_std_11)
-	# libgme's CMakeLists.txt already links this
-	#target_link_libraries(gme PRIVATE ZLIB::ZLIB)
-endif()
diff --git a/thirdparty/cpm-png.cmake b/thirdparty/cpm-png.cmake
deleted file mode 100644
index f16ac037b0cc9c077f3ef315b67b430e68cf9b40..0000000000000000000000000000000000000000
--- a/thirdparty/cpm-png.cmake
+++ /dev/null
@@ -1,69 +0,0 @@
-CPMAddPackage(
-	NAME png
-	VERSION 1.6.38
-	URL "https://github.com/glennrp/libpng/archive/refs/tags/v1.6.38.zip"
-	# png cmake build is broken on msys/mingw32
-	DOWNLOAD_ONLY YES
-)
-
-if(png_ADDED)
-	# Since png's cmake build is broken, we're going to create a target manually
-	set(
-		PNG_SOURCES
-		png.h
-		pngconf.h
-		pngpriv.h
-		pngdebug.h
-		pnginfo.h
-		pngstruct.h
-		png.c
-		pngerror.c
-		pngget.c
-		pngmem.c
-		pngpread.c
-		pngread.c
-		pngrio.c
-		pngrtran.c
-		pngrutil.c
-		pngset.c
-		pngtrans.c
-		pngwio.c
-		pngwrite.c
-		pngwtran.c
-		pngwutil.c
-	)
-	list(TRANSFORM PNG_SOURCES PREPEND "${png_SOURCE_DIR}/")
-
-	add_custom_command(
-		OUTPUT "${png_BINARY_DIR}/include/png.h" "${png_BINARY_DIR}/include/pngconf.h"
-		COMMAND ${CMAKE_COMMAND} -E copy "${png_SOURCE_DIR}/png.h" "${png_SOURCE_DIR}/pngconf.h" "${png_BINARY_DIR}/include"
-		DEPENDS "${png_SOURCE_DIR}/png.h" "${png_SOURCE_DIR}/pngconf.h"
-		VERBATIM
-	)
-	add_custom_command(
-		OUTPUT "${png_BINARY_DIR}/include/pnglibconf.h"
-		COMMAND ${CMAKE_COMMAND} -E copy "${png_SOURCE_DIR}/scripts/pnglibconf.h.prebuilt" "${png_BINARY_DIR}/include/pnglibconf.h"
-		DEPENDS "${png_SOURCE_DIR}/scripts/pnglibconf.h.prebuilt"
-		VERBATIM
-	)
-	list(
-		APPEND PNG_SOURCES
-		"${png_BINARY_DIR}/include/png.h"
-		"${png_BINARY_DIR}/include/pngconf.h"
-		"${png_BINARY_DIR}/include/pnglibconf.h"
-	)
-	add_library(png "${SRB2_INTERNAL_LIBRARY_TYPE}" ${PNG_SOURCES})
-
-	# Disable ARM NEON since having it automatic breaks libpng external build on clang for some reason
-	target_compile_definitions(png PRIVATE -DPNG_ARM_NEON_OPT=0)
-
-	# The png includes need to be available to consumers
-	target_include_directories(png PUBLIC "${png_BINARY_DIR}/include")
-
-	# ... and these also need to be present only for png build
-	target_include_directories(png PRIVATE "${ZLIB_SOURCE_DIR}")
-	target_include_directories(png PRIVATE "${ZLIB_BINARY_DIR}")
-	target_include_directories(png PRIVATE "${png_BINARY_DIR}")
-	target_link_libraries(png PRIVATE ZLIB::ZLIB)
-	add_library(PNG::PNG ALIAS png)
-endif()
diff --git a/thirdparty/cpm-sdl2-mixer.cmake b/thirdparty/cpm-sdl2-mixer.cmake
deleted file mode 100644
index b7dfeae0d3eab254651f0c5e6e69e7af0626012e..0000000000000000000000000000000000000000
--- a/thirdparty/cpm-sdl2-mixer.cmake
+++ /dev/null
@@ -1,22 +0,0 @@
-CPMAddPackage(
-	NAME SDL2_mixer
-	VERSION 2.6.2
-	URL "https://github.com/libsdl-org/SDL_mixer/archive/refs/tags/release-2.6.2.zip"
-	EXCLUDE_FROM_ALL ON
-	OPTIONS
-		"BUILD_SHARED_LIBS ${SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES}"
-		"SDL2MIXER_INSTALL OFF"
-		"SDL2MIXER_DEPS_SHARED OFF"
-		"SDL2MIXER_SAMPLES OFF"
-		"SDL2MIXER_VENDORED ON"
-		"SDL2MIXER_FLAC ON"
-		"SDL2MIXER_FLAC_LIBFLAC OFF"
-		"SDL2MIXER_FLAC_DRFLAC ON"
-		"SDL2MIXER_MOD OFF"
-		"SDL2MIXER_MP3 ON"
-		"SDL2MIXER_MP3_DRMP3 ON"
-		"SDL2MIXER_MIDI ON"
-		"SDL2MIXER_OPUS OFF"
-		"SDL2MIXER_VORBIS STB"
-		"SDL2MIXER_WAVE ON"
-)
diff --git a/thirdparty/cpm-sdl2.cmake b/thirdparty/cpm-sdl2.cmake
deleted file mode 100644
index 0bb404e4c90fc6e9e5ff79314f0703a1aa4ae9a6..0000000000000000000000000000000000000000
--- a/thirdparty/cpm-sdl2.cmake
+++ /dev/null
@@ -1,28 +0,0 @@
-set(
-	internal_sdl2_options
-
-		"BUILD_SHARED_LIBS ${SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES}"
-		"SDL_SHARED ${SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES}"
-		"SDL_STATIC ${NOT_SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES}"
-		"SDL_TEST OFF"
-		"SDL2_DISABLE_INSTALL ON"
-)
-
-if(${CMAKE_SYSTEM} MATCHES Windows)
-	list(APPEND internal_sdl2_options "SDL2_DISABLE_SDL2MAIN OFF")
-endif()
-if(${CMAKE_SYSTEM} MATCHES Darwin)
-	list(APPEND internal_sdl2_options "SDL2_DISABLE_SDL2MAIN OFF")
-endif()
-if(${CMAKE_SYSTEM} MATCHES Linux)
-	list(APPEND internal_sdl2_options "SDL2_DISABLE_SDL2MAIN ON")
-endif()
-
-CPMAddPackage(
-	NAME SDL2
-	VERSION 2.28.5
-	GITHUB_REPOSITORY "libsdl-org/SDL"
-	GIT_TAG release-2.28.5
-	EXCLUDE_FROM_ALL ON
-	OPTIONS ${internal_sdl2_options}
-)
diff --git a/thirdparty/cpm-zlib.cmake b/thirdparty/cpm-zlib.cmake
deleted file mode 100644
index f0a2c33aee8c483d82b4ab26e1d0be2143fd9e16..0000000000000000000000000000000000000000
--- a/thirdparty/cpm-zlib.cmake
+++ /dev/null
@@ -1,18 +0,0 @@
-CPMAddPackage(
-	NAME zlib
-	VERSION 1.3.1
-	GITHUB_REPOSITORY "madler/zlib"
-	GIT_TAG v1.3.1
-	EXCLUDE_FROM_ALL
-	OPTIONS
-		"ZLIB_BUILD_EXAMPLES OFF"
-)
-
-if(zlib_ADDED)
-	if(SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES)
-		add_library(ZLIB::ZLIB ALIAS zlib)
-	endif()
-	if(NOT_SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES)
-		add_library(ZLIB::ZLIB ALIAS zlibstatic)
-	endif()
-endif()
diff --git a/thirdparty/cpm-curl.cmake b/thirdparty/curl.cmake
similarity index 55%
rename from thirdparty/cpm-curl.cmake
rename to thirdparty/curl.cmake
index 3d8c6e61d46dee6f06f4e6d69beb09d1605f6584..5c3aa26e35882d64ca8a6cf99517d28e9fc56dcc 100644
--- a/thirdparty/cpm-curl.cmake
+++ b/thirdparty/curl.cmake
@@ -1,8 +1,16 @@
+if(TARGET CURL::libcurl)
+    return()
+endif()
+
+message(STATUS "Third-party: creating target 'CURL::libcurl'")
+
+set(CURL_ENABLE_EXPORT_TARGET OFF CACHE BOOL "" FORCE)
+
 set(
 	internal_curl_options
 
 	"BUILD_CURL_EXE OFF"
-	"BUILD_SHARED_LIBS ${SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES}"
+	"BUILD_SHARED_LIBS OFF"
 	"CURL_DISABLE_TESTS ON"
 	"HTTP_ONLY ON"
 	"CURL_DISABLE_CRYPTO_AUTH ON"
@@ -26,10 +34,25 @@ if(${CMAKE_SYSTEM} MATCHES Linux)
 	list(APPEND internal_curl_options "CURL_USE_OPENSSL ON")
 endif()
 
-CPMAddPackage(
-	NAME curl
-	VERSION 7.86.0
-	URL "https://github.com/curl/curl/archive/refs/tags/curl-7_86_0.zip"
-	EXCLUDE_FROM_ALL ON
-	OPTIONS ${internal_curl_options}
-)
+include(FetchContent)
+
+if (CURL_USE_THIRDPARTY)
+	FetchContent_Declare(
+		curl
+		VERSION 7.88.1
+		GITHUB_REPOSITORY "curl/curl"
+		GIT_TAG curl-7_88_1
+		EXCLUDE_FROM_ALL ON
+		OPTIONS ${internal_curl_options}
+	)
+else()
+	FetchContent_Declare(
+		curl
+		SOURCE_DIR "${CMAKE_SOURCE_DIR}/thirdparty/curl/"
+		EXCLUDE_FROM_ALL ON
+		OPTIONS ${internal_curl_options}
+	)
+endif()
+
+FetchContent_MakeAvailable(curl)
+
diff --git a/thirdparty/libapng.cmake b/thirdparty/libapng.cmake
new file mode 100644
index 0000000000000000000000000000000000000000..f4bc50ff1d301b58bf91c44bfe40986c5c987654
--- /dev/null
+++ b/thirdparty/libapng.cmake
@@ -0,0 +1,38 @@
+if(TARGET libapng_static)
+    return()
+endif()
+
+message(STATUS "Third-party: creating target 'libapng_static'")
+
+set(PNG_SHARED OFF CACHE BOOL "" FORCE)
+set(PNG_BUILD_ZLIB ON CACHE BOOL "" FORCE)
+
+include(FetchContent)
+
+	FetchContent_Declare(
+		libapng-local
+		SOURCE_DIR "${CMAKE_SOURCE_DIR}/thirdparty/libapng/"
+		EXCLUDE_FROM_ALL ON
+		DOWNLOAD_ONLY YES
+		OPTION
+			"PNG_SHARED OFF"
+			"PNG_EXECUTABLES OFF"
+			"PNG_TESTS OFF"
+			"PNG_BUILD_ZLIB ON"
+	)
+
+FetchContent_MakeAvailable(libapng-local)
+
+#add_custom_command(
+#OUTPUT ${libapng-local_BINARY_DIR}/CMakeLists.txt
+#COMMAND ${CMAKE_COMMAND}
+#  -Din_file:FILEPATH=${libapng-locall_SOURCE_DIR}/CMakeLists.txt
+#  -Dpatch_file:FILEPATH=${CMAKE_CURRENT_SOURCE_DIR}/thirdparty/00-libapng-ZLIB.patch
+#  -Dout_file:FILEPATH=${libapng-local_BINARY_DIR}/CMakeLists.txt
+#  -P ${CMAKE_CURRENT_SOURCE_DIR}/cmake/PatchFile.cmake
+#DEPENDS ${libapng-local_SOURCE_DIR}/CMakeLists.txt
+#)
+
+set(libapng_INCLUDE_DIRS "${CMAKE_CURRENT_SOURCE_DIR}/libapng" "${libapng_BINARY_DIR}" CACHE PATH "" FORCE)
+
+set(libapng_HEADER "${CMAKE_CURRENT_SOURCE_DIR}/libapng/png.h" "${CMAKE_CURRENT_SOURCE_DIR}/libapng/pngconf.h" CACHE PATH "" FORCE)
diff --git a/thirdparty/cpm-openmpt.cmake b/thirdparty/libopenmpt.cmake
similarity index 82%
rename from thirdparty/cpm-openmpt.cmake
rename to thirdparty/libopenmpt.cmake
index 01f7ff75f64d915799e432f2923a2c7e8c344466..256b4c406b99b73bf96e9488316b1093515f65c9 100644
--- a/thirdparty/cpm-openmpt.cmake
+++ b/thirdparty/libopenmpt.cmake
@@ -1,13 +1,33 @@
-CPMAddPackage(
-	NAME openmpt
-	VERSION 0.4.30
-	URL "https://github.com/OpenMPT/openmpt/archive/refs/tags/libopenmpt-0.4.30.zip"
-	DOWNLOAD_ONLY ON
-)
+if(TARGET libopenmpt)
+    #return()
+endif()
+
+message(STATUS "Third-party: creating target 'libopenmpt'")
+
+
+include(FetchContent)
+
+if (libopenmpt_USE_THIRDPARTY)
+	FetchContent_Declare(
+		libopenmpt-local
+		GITHUB_REPOSITORY openmpt
+		GIT_TAG libopenmpt-0.4.38
+		version 0.4.38
+		EXCLUDE_FROM_ALL ON
+	)
+else()
+	FetchContent_Declare(
+		libopenmpt-local
+		SOURCE_DIR "${CMAKE_SOURCE_DIR}/thirdparty/libopenmpt/"
+		EXCLUDE_FROM_ALL ON
+	)
+endif()
+
+FetchContent_MakeAvailable(libopenmpt)
 
-if(openmpt_ADDED)
+if(aaaa-libopenmpt-local_ADDED)
 	set(
-		openmpt_SOURCES
+		libopenmpt-local_SOURCES
 
 		# minimp3
 		# -DMPT_WITH_MINIMP3
@@ -264,26 +284,26 @@ if(openmpt_ADDED)
 		libopenmpt/libopenmpt_impl.cpp
 		libopenmpt/libopenmpt_ext_impl.cpp
 	)
-	list(TRANSFORM openmpt_SOURCES PREPEND "${openmpt_SOURCE_DIR}/")
+	list(TRANSFORM libopenmpt-local_SOURCES PREPEND "${libopenmpt-local_SOURCE_DIR}/")
 
 	# -DLIBOPENMPT_BUILD
 	configure_file("openmpt_svn_version.h" "svn_version.h")
-	add_library(openmpt "${SRB2_INTERNAL_LIBRARY_TYPE}" ${openmpt_SOURCES} ${CMAKE_CURRENT_BINARY_DIR}/svn_version.h)
+	add_library(libopenmpt STATIC ${libopenmpt-local_SOURCES} ${CMAKE_CURRENT_BINARY_DIR}/svn_version.h)
 	if("${CMAKE_C_COMPILER_ID}" STREQUAL GNU OR "${CMAKE_C_COMPILER_ID}" STREQUAL Clang OR "${CMAKE_C_COMPILER_ID}" STREQUAL AppleClang)
-		target_compile_options(openmpt PRIVATE "-g0")
+		target_compile_options(libopenmpt PRIVATE "-g0")
 	endif()
 	if("${CMAKE_SYSTEM_NAME}" STREQUAL Windows AND "${CMAKE_C_COMPILER_ID}" STREQUAL MSVC)
-		target_link_libraries(openmpt PRIVATE Rpcrt4)
+		target_link_libraries(libopenmpt PRIVATE Rpcrt4)
 	endif()
-	target_compile_features(openmpt PRIVATE cxx_std_11)
-	target_compile_definitions(openmpt PRIVATE -DLIBOPENMPT_BUILD)
+	target_compile_features(libopenmpt PRIVATE cxx_std_11)
+	target_compile_definitions(libopenmpt PRIVATE -DLIBOPENMPT_BUILD)
 
-	target_include_directories(openmpt PRIVATE "${openmpt_SOURCE_DIR}/common")
-	target_include_directories(openmpt PRIVATE "${openmpt_SOURCE_DIR}/src")
-	target_include_directories(openmpt PRIVATE "${openmpt_SOURCE_DIR}/include")
-	target_include_directories(openmpt PRIVATE "${openmpt_SOURCE_DIR}")
-	target_include_directories(openmpt PRIVATE "${CMAKE_CURRENT_BINARY_DIR}")
+	target_include_directories(libopenmpt PRIVATE "${libopenmpt-local_SOURCE_DIR}/common")
+	target_include_directories(libopenmpt PRIVATE "${libopenmpt-local_SOURCE_DIR}/src")
+	target_include_directories(libopenmpt PRIVATE "${libopenmpt-local_SOURCE_DIR}/include")
+	target_include_directories(libopenmpt PRIVATE "${libopenmpt-local_SOURCE_DIR}")
+	target_include_directories(libopenmpt PRIVATE "${CMAKE_CURRENT_BINARY_DIR}")
 
 	# I wish this wasn't necessary, but it is
-	target_include_directories(openmpt PUBLIC "${openmpt_SOURCE_DIR}")
+	target_include_directories(libopenmpt PUBLIC "${libopenmpt-local_SOURCE_DIR}")
 endif()
diff --git a/thirdparty/libpng-1.6.40-apng.patch b/thirdparty/libpng-1.6.40-apng.patch
new file mode 100644
index 0000000000000000000000000000000000000000..c5b870004ad2f7a82df6bbbc061c24cc8f5a5393
--- /dev/null
+++ b/thirdparty/libpng-1.6.40-apng.patch
@@ -0,0 +1,1728 @@
+diff -Naru libpng-1.6.40.org/png.h libpng-1.6.40/png.h
+--- libpng-1.6.40.org/png.h	2023-09-10 11:12:23.044481879 +0900
++++ libpng-1.6.40/png.h	2023-09-10 11:08:58.964075833 +0900
+@@ -330,6 +330,10 @@
+ #   include "pnglibconf.h"
+ #endif
+ 
++#define PNG_APNG_SUPPORTED
++#define PNG_READ_APNG_SUPPORTED
++#define PNG_WRITE_APNG_SUPPORTED
++
+ #ifndef PNG_VERSION_INFO_ONLY
+ /* Machine specific configuration. */
+ #  include "pngconf.h"
+@@ -425,6 +429,17 @@
+  * See pngconf.h for base types that vary by machine/system
+  */
+ 
++#ifdef PNG_APNG_SUPPORTED
++/* dispose_op flags from inside fcTL */
++#define PNG_DISPOSE_OP_NONE        0x00U
++#define PNG_DISPOSE_OP_BACKGROUND  0x01U
++#define PNG_DISPOSE_OP_PREVIOUS    0x02U
++
++/* blend_op flags from inside fcTL */
++#define PNG_BLEND_OP_SOURCE        0x00U
++#define PNG_BLEND_OP_OVER          0x01U
++#endif /* PNG_APNG_SUPPORTED */
++
+ /* This triggers a compiler error in png.c, if png.c and png.h
+  * do not agree upon the version number.
+  */
+@@ -746,6 +761,10 @@
+ #define PNG_INFO_sCAL 0x4000U  /* ESR, 1.0.6 */
+ #define PNG_INFO_IDAT 0x8000U  /* ESR, 1.0.6 */
+ #define PNG_INFO_eXIf 0x10000U /* GR-P, 1.6.31 */
++#ifdef PNG_APNG_SUPPORTED
++#define PNG_INFO_acTL 0x20000U
++#define PNG_INFO_fcTL 0x40000U
++#endif
+ 
+ /* This is used for the transformation routines, as some of them
+  * change these values for the row.  It also should enable using
+@@ -783,6 +802,10 @@
+ #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+ typedef PNG_CALLBACK(void, *png_progressive_info_ptr, (png_structp, png_infop));
+ typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_infop));
++#ifdef PNG_APNG_SUPPORTED
++typedef PNG_CALLBACK(void, *png_progressive_frame_ptr, (png_structp,
++    png_uint_32));
++#endif
+ 
+ /* The following callback receives png_uint_32 row_number, int pass for the
+  * png_bytep data of the row.  When transforming an interlaced image the
+@@ -3226,6 +3249,74 @@
+ /*******************************************************************************
+  *  END OF HARDWARE AND SOFTWARE OPTIONS
+  ******************************************************************************/
++#ifdef PNG_APNG_SUPPORTED
++PNG_EXPORT(250, png_uint_32, png_get_acTL, (png_structp png_ptr,
++   png_infop info_ptr, png_uint_32 *num_frames, png_uint_32 *num_plays));
++
++PNG_EXPORT(251, png_uint_32, png_set_acTL, (png_structp png_ptr,
++   png_infop info_ptr, png_uint_32 num_frames, png_uint_32 num_plays));
++
++PNG_EXPORT(252, png_uint_32, png_get_num_frames, (png_structp png_ptr,
++   png_infop info_ptr));
++
++PNG_EXPORT(253, png_uint_32, png_get_num_plays, (png_structp png_ptr,
++   png_infop info_ptr));
++
++PNG_EXPORT(254, png_uint_32, png_get_next_frame_fcTL,
++   (png_structp png_ptr, png_infop info_ptr, png_uint_32 *width,
++   png_uint_32 *height, png_uint_32 *x_offset, png_uint_32 *y_offset,
++   png_uint_16 *delay_num, png_uint_16 *delay_den, png_byte *dispose_op,
++   png_byte *blend_op));
++
++PNG_EXPORT(255, png_uint_32, png_set_next_frame_fcTL,
++   (png_structp png_ptr, png_infop info_ptr, png_uint_32 width,
++   png_uint_32 height, png_uint_32 x_offset, png_uint_32 y_offset,
++   png_uint_16 delay_num, png_uint_16 delay_den, png_byte dispose_op,
++   png_byte blend_op));
++
++PNG_EXPORT(256, png_uint_32, png_get_next_frame_width,
++   (png_structp png_ptr, png_infop info_ptr));
++PNG_EXPORT(257, png_uint_32, png_get_next_frame_height,
++   (png_structp png_ptr, png_infop info_ptr));
++PNG_EXPORT(258, png_uint_32, png_get_next_frame_x_offset,
++   (png_structp png_ptr, png_infop info_ptr));
++PNG_EXPORT(259, png_uint_32, png_get_next_frame_y_offset,
++   (png_structp png_ptr, png_infop info_ptr));
++PNG_EXPORT(260, png_uint_16, png_get_next_frame_delay_num,
++   (png_structp png_ptr, png_infop info_ptr));
++PNG_EXPORT(261, png_uint_16, png_get_next_frame_delay_den,
++   (png_structp png_ptr, png_infop info_ptr));
++PNG_EXPORT(262, png_byte, png_get_next_frame_dispose_op,
++   (png_structp png_ptr, png_infop info_ptr));
++PNG_EXPORT(263, png_byte, png_get_next_frame_blend_op,
++   (png_structp png_ptr, png_infop info_ptr));
++PNG_EXPORT(264, png_byte, png_get_first_frame_is_hidden,
++   (png_structp png_ptr, png_infop info_ptr));
++PNG_EXPORT(265, png_uint_32, png_set_first_frame_is_hidden,
++   (png_structp png_ptr, png_infop info_ptr, png_byte is_hidden));
++
++#ifdef PNG_READ_APNG_SUPPORTED
++PNG_EXPORT(266, void, png_read_frame_head, (png_structp png_ptr,
++   png_infop info_ptr));
++#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
++PNG_EXPORT(267, void, png_set_progressive_frame_fn, (png_structp png_ptr,
++   png_progressive_frame_ptr frame_info_fn,
++   png_progressive_frame_ptr frame_end_fn));
++#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
++#endif /* PNG_READ_APNG_SUPPORTED */
++
++#ifdef PNG_WRITE_APNG_SUPPORTED
++PNG_EXPORT(268, void, png_write_frame_head, (png_structp png_ptr,
++   png_infop info_ptr, png_bytepp row_pointers,
++   png_uint_32 width, png_uint_32 height,
++   png_uint_32 x_offset, png_uint_32 y_offset,
++   png_uint_16 delay_num, png_uint_16 delay_den, png_byte dispose_op,
++   png_byte blend_op));
++
++PNG_EXPORT(269, void, png_write_frame_tail, (png_structp png_ptr,
++   png_infop info_ptr));
++#endif /* PNG_WRITE_APNG_SUPPORTED */
++#endif /* PNG_APNG_SUPPORTED */
+ 
+ /* Maintainer: Put new public prototypes here ^, in libpng.3, in project
+  * defs, and in scripts/symbols.def.
+@@ -3235,7 +3326,11 @@
+  * one to use is one more than this.)
+  */
+ #ifdef PNG_EXPORT_LAST_ORDINAL
++#ifdef PNG_APNG_SUPPORTED
++  PNG_EXPORT_LAST_ORDINAL(269);
++#else
+   PNG_EXPORT_LAST_ORDINAL(249);
++#endif /* PNG_APNG_SUPPORTED */
+ #endif
+ 
+ #ifdef __cplusplus
+diff -Naru libpng-1.6.40.org/pngget.c libpng-1.6.40/pngget.c
+--- libpng-1.6.40.org/pngget.c	2023-09-10 11:09:32.954139030 +0900
++++ libpng-1.6.40/pngget.c	2023-09-10 11:08:58.922075757 +0900
+@@ -1257,4 +1257,166 @@
+ #  endif
+ #endif
+ 
++#ifdef PNG_APNG_SUPPORTED
++png_uint_32 PNGAPI
++png_get_acTL(png_structp png_ptr, png_infop info_ptr,
++             png_uint_32 *num_frames, png_uint_32 *num_plays)
++{
++    png_debug1(1, "in %s retrieval function", "acTL");
++
++    if (png_ptr != NULL && info_ptr != NULL &&
++        (info_ptr->valid & PNG_INFO_acTL) &&
++        num_frames != NULL && num_plays != NULL)
++    {
++        *num_frames = info_ptr->num_frames;
++        *num_plays = info_ptr->num_plays;
++        return (1);
++    }
++
++    return (0);
++}
++
++png_uint_32 PNGAPI
++png_get_num_frames(png_structp png_ptr, png_infop info_ptr)
++{
++    png_debug(1, "in png_get_num_frames()");
++
++    if (png_ptr != NULL && info_ptr != NULL)
++        return (info_ptr->num_frames);
++    return (0);
++}
++
++png_uint_32 PNGAPI
++png_get_num_plays(png_structp png_ptr, png_infop info_ptr)
++{
++    png_debug(1, "in png_get_num_plays()");
++
++    if (png_ptr != NULL && info_ptr != NULL)
++        return (info_ptr->num_plays);
++    return (0);
++}
++
++png_uint_32 PNGAPI
++png_get_next_frame_fcTL(png_structp png_ptr, png_infop info_ptr,
++             png_uint_32 *width, png_uint_32 *height,
++             png_uint_32 *x_offset, png_uint_32 *y_offset,
++             png_uint_16 *delay_num, png_uint_16 *delay_den,
++             png_byte *dispose_op, png_byte *blend_op)
++{
++    png_debug1(1, "in %s retrieval function", "fcTL");
++
++    if (png_ptr != NULL && info_ptr != NULL &&
++        (info_ptr->valid & PNG_INFO_fcTL) &&
++        width != NULL && height != NULL &&
++        x_offset != NULL && y_offset != NULL &&
++        delay_num != NULL && delay_den != NULL &&
++        dispose_op != NULL && blend_op != NULL)
++    {
++        *width = info_ptr->next_frame_width;
++        *height = info_ptr->next_frame_height;
++        *x_offset = info_ptr->next_frame_x_offset;
++        *y_offset = info_ptr->next_frame_y_offset;
++        *delay_num = info_ptr->next_frame_delay_num;
++        *delay_den = info_ptr->next_frame_delay_den;
++        *dispose_op = info_ptr->next_frame_dispose_op;
++        *blend_op = info_ptr->next_frame_blend_op;
++        return (1);
++    }
++
++    return (0);
++}
++
++png_uint_32 PNGAPI
++png_get_next_frame_width(png_structp png_ptr, png_infop info_ptr)
++{
++    png_debug(1, "in png_get_next_frame_width()");
++
++    if (png_ptr != NULL && info_ptr != NULL)
++        return (info_ptr->next_frame_width);
++    return (0);
++}
++
++png_uint_32 PNGAPI
++png_get_next_frame_height(png_structp png_ptr, png_infop info_ptr)
++{
++    png_debug(1, "in png_get_next_frame_height()");
++
++    if (png_ptr != NULL && info_ptr != NULL)
++        return (info_ptr->next_frame_height);
++    return (0);
++}
++
++png_uint_32 PNGAPI
++png_get_next_frame_x_offset(png_structp png_ptr, png_infop info_ptr)
++{
++    png_debug(1, "in png_get_next_frame_x_offset()");
++
++    if (png_ptr != NULL && info_ptr != NULL)
++        return (info_ptr->next_frame_x_offset);
++    return (0);
++}
++
++png_uint_32 PNGAPI
++png_get_next_frame_y_offset(png_structp png_ptr, png_infop info_ptr)
++{
++    png_debug(1, "in png_get_next_frame_y_offset()");
++
++    if (png_ptr != NULL && info_ptr != NULL)
++        return (info_ptr->next_frame_y_offset);
++    return (0);
++}
++
++png_uint_16 PNGAPI
++png_get_next_frame_delay_num(png_structp png_ptr, png_infop info_ptr)
++{
++    png_debug(1, "in png_get_next_frame_delay_num()");
++
++    if (png_ptr != NULL && info_ptr != NULL)
++        return (info_ptr->next_frame_delay_num);
++    return (0);
++}
++
++png_uint_16 PNGAPI
++png_get_next_frame_delay_den(png_structp png_ptr, png_infop info_ptr)
++{
++    png_debug(1, "in png_get_next_frame_delay_den()");
++
++    if (png_ptr != NULL && info_ptr != NULL)
++        return (info_ptr->next_frame_delay_den);
++    return (0);
++}
++
++png_byte PNGAPI
++png_get_next_frame_dispose_op(png_structp png_ptr, png_infop info_ptr)
++{
++    png_debug(1, "in png_get_next_frame_dispose_op()");
++
++    if (png_ptr != NULL && info_ptr != NULL)
++        return (info_ptr->next_frame_dispose_op);
++    return (0);
++}
++
++png_byte PNGAPI
++png_get_next_frame_blend_op(png_structp png_ptr, png_infop info_ptr)
++{
++    png_debug(1, "in png_get_next_frame_blend_op()");
++
++    if (png_ptr != NULL && info_ptr != NULL)
++        return (info_ptr->next_frame_blend_op);
++    return (0);
++}
++
++png_byte PNGAPI
++png_get_first_frame_is_hidden(png_structp png_ptr, png_infop info_ptr)
++{
++    png_debug(1, "in png_first_frame_is_hidden()");
++
++    if (png_ptr != NULL)
++       return (png_byte)(png_ptr->apng_flags & PNG_FIRST_FRAME_HIDDEN);
++
++    PNG_UNUSED(info_ptr)
++
++    return 0;
++}
++#endif /* PNG_APNG_SUPPORTED */
+ #endif /* READ || WRITE */
+diff -Naru libpng-1.6.40.org/pnginfo.h libpng-1.6.40/pnginfo.h
+--- libpng-1.6.40.org/pnginfo.h	2022-11-24 08:37:51.507052183 +0900
++++ libpng-1.6.40/pnginfo.h	2023-09-10 11:08:58.922075757 +0900
+@@ -263,5 +263,18 @@
+    png_bytepp row_pointers;        /* the image bits */
+ #endif
+ 
++#ifdef PNG_APNG_SUPPORTED
++   png_uint_32 num_frames; /* including default image */
++   png_uint_32 num_plays;
++   png_uint_32 next_frame_width;
++   png_uint_32 next_frame_height;
++   png_uint_32 next_frame_x_offset;
++   png_uint_32 next_frame_y_offset;
++   png_uint_16 next_frame_delay_num;
++   png_uint_16 next_frame_delay_den;
++   png_byte next_frame_dispose_op;
++   png_byte next_frame_blend_op;
++#endif
++
+ };
+ #endif /* PNGINFO_H */
+diff -Naru libpng-1.6.40.org/pngpread.c libpng-1.6.40/pngpread.c
+--- libpng-1.6.40.org/pngpread.c	2022-11-24 08:37:51.507052183 +0900
++++ libpng-1.6.40/pngpread.c	2023-09-10 11:08:58.922075757 +0900
+@@ -195,6 +195,106 @@
+ 
+    chunk_name = png_ptr->chunk_name;
+ 
++#ifdef PNG_READ_APNG_SUPPORTED
++   if (png_ptr->num_frames_read > 0 &&
++       png_ptr->num_frames_read < info_ptr->num_frames)
++   {
++      if (chunk_name == png_IDAT)
++      {
++         /* Discard trailing IDATs for the first frame */
++         if (png_ptr->mode & PNG_HAVE_fcTL || png_ptr->num_frames_read > 1)
++            png_error(png_ptr, "out of place IDAT");
++
++         if (png_ptr->push_length + 4 > png_ptr->buffer_size)
++         {
++            png_push_save_buffer(png_ptr);
++            return;
++         }
++
++         png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
++         return;
++      }
++      else if (chunk_name == png_fdAT)
++      {
++         if (png_ptr->buffer_size < 4)
++         {
++            png_push_save_buffer(png_ptr);
++            return;
++         }
++
++         png_ensure_sequence_number(png_ptr, 4);
++
++         if (!(png_ptr->mode & PNG_HAVE_fcTL))
++         {
++            /* Discard trailing fdATs for frames other than the first */
++            if (png_ptr->num_frames_read < 2)
++               png_error(png_ptr, "out of place fdAT");
++
++            if (png_ptr->push_length + 4 > png_ptr->buffer_size)
++            {
++               png_push_save_buffer(png_ptr);
++               return;
++            }
++
++            png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
++            return;
++         }
++
++         else
++         {
++            /* frame data follows */
++            png_ptr->idat_size = png_ptr->push_length - 4;
++            png_ptr->mode |= PNG_HAVE_IDAT;
++            png_ptr->process_mode = PNG_READ_IDAT_MODE;
++
++            return;
++         }
++      }
++
++      else if (chunk_name == png_fcTL)
++      {
++         if (png_ptr->push_length + 4 > png_ptr->buffer_size)
++         {
++            png_push_save_buffer(png_ptr);
++            return;
++         }
++
++         png_read_reset(png_ptr);
++         png_ptr->mode &= ~PNG_HAVE_fcTL;
++
++         png_handle_fcTL(png_ptr, info_ptr, png_ptr->push_length);
++
++         if (!(png_ptr->mode & PNG_HAVE_fcTL))
++            png_error(png_ptr, "missing required fcTL chunk");
++
++         png_read_reinit(png_ptr, info_ptr);
++         png_progressive_read_reset(png_ptr);
++
++         if (png_ptr->frame_info_fn != NULL)
++            (*(png_ptr->frame_info_fn))(png_ptr, png_ptr->num_frames_read);
++
++         png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
++
++         return;
++      }
++
++      else
++      {
++         if (png_ptr->push_length + 4 > png_ptr->buffer_size)
++         {
++            png_push_save_buffer(png_ptr);
++            return;
++         }
++         png_warning(png_ptr, "Skipped (ignored) a chunk "
++                              "between APNG chunks");
++         png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
++         return;
++      }
++
++      return;
++   }
++#endif /* PNG_READ_APNG_SUPPORTED */
++
+    if (chunk_name == png_IDAT)
+    {
+       if ((png_ptr->mode & PNG_AFTER_IDAT) != 0)
+@@ -261,6 +361,9 @@
+ 
+    else if (chunk_name == png_IDAT)
+    {
++#ifdef PNG_READ_APNG_SUPPORTED
++      png_have_info(png_ptr, info_ptr);
++#endif
+       png_ptr->idat_size = png_ptr->push_length;
+       png_ptr->process_mode = PNG_READ_IDAT_MODE;
+       png_push_have_info(png_ptr, info_ptr);
+@@ -406,6 +509,30 @@
+       png_handle_iTXt(png_ptr, info_ptr, png_ptr->push_length);
+    }
+ #endif
++#ifdef PNG_READ_APNG_SUPPORTED
++   else if (chunk_name == png_acTL)
++   {
++      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
++      {
++         png_push_save_buffer(png_ptr);
++         return;
++      }
++
++      png_handle_acTL(png_ptr, info_ptr, png_ptr->push_length);
++   }
++
++   else if (chunk_name == png_fcTL)
++   {
++      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
++      {
++         png_push_save_buffer(png_ptr);
++         return;
++      }
++
++      png_handle_fcTL(png_ptr, info_ptr, png_ptr->push_length);
++   }
++
++#endif /* PNG_READ_APNG_SUPPORTED */
+ 
+    else
+    {
+@@ -539,7 +666,11 @@
+       png_byte chunk_tag[4];
+ 
+       /* TODO: this code can be commoned up with the same code in push_read */
++#ifdef PNG_READ_APNG_SUPPORTED
++      PNG_PUSH_SAVE_BUFFER_IF_LT(12)
++#else
+       PNG_PUSH_SAVE_BUFFER_IF_LT(8)
++#endif
+       png_push_fill_buffer(png_ptr, chunk_length, 4);
+       png_ptr->push_length = png_get_uint_31(png_ptr, chunk_length);
+       png_reset_crc(png_ptr);
+@@ -547,17 +678,64 @@
+       png_ptr->chunk_name = PNG_CHUNK_FROM_STRING(chunk_tag);
+       png_ptr->mode |= PNG_HAVE_CHUNK_HEADER;
+ 
++#ifdef PNG_READ_APNG_SUPPORTED
++      if (png_ptr->chunk_name != png_fdAT && png_ptr->num_frames_read > 0)
++      {
++          if (png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED)
++          {
++              png_ptr->process_mode = PNG_READ_CHUNK_MODE;
++              if (png_ptr->frame_end_fn != NULL)
++                 (*(png_ptr->frame_end_fn))(png_ptr, png_ptr->num_frames_read);
++              png_ptr->num_frames_read++;
++              return;
++          }
++          else
++          {
++              if (png_ptr->chunk_name == png_IEND)
++                  png_error(png_ptr, "Not enough image data");
++              if (png_ptr->push_length + 4 > png_ptr->buffer_size)
++              {
++                 png_push_save_buffer(png_ptr);
++                 return;
++              }
++              png_warning(png_ptr, "Skipping (ignoring) a chunk between "
++                                   "APNG chunks");
++              png_crc_finish(png_ptr, png_ptr->push_length);
++              png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
++              return;
++          }
++      }
++      else
++#endif
++#ifdef PNG_READ_APNG_SUPPORTED
++      if (png_ptr->chunk_name != png_IDAT && png_ptr->num_frames_read == 0)
++#else
+       if (png_ptr->chunk_name != png_IDAT)
++#endif
+       {
+          png_ptr->process_mode = PNG_READ_CHUNK_MODE;
+ 
+          if ((png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED) == 0)
+             png_error(png_ptr, "Not enough compressed data");
+ 
++#ifdef PNG_READ_APNG_SUPPORTED
++         if (png_ptr->frame_end_fn != NULL)
++            (*(png_ptr->frame_end_fn))(png_ptr, png_ptr->num_frames_read);
++         png_ptr->num_frames_read++;
++#endif
++
+          return;
+       }
+ 
+       png_ptr->idat_size = png_ptr->push_length;
++
++#ifdef PNG_READ_APNG_SUPPORTED
++      if (png_ptr->num_frames_read > 0)
++      {
++         png_ensure_sequence_number(png_ptr, 4);
++         png_ptr->idat_size -= 4;
++      }
++#endif
+    }
+ 
+    if (png_ptr->idat_size != 0 && png_ptr->save_buffer_size != 0)
+@@ -631,6 +809,15 @@
+    if (!(buffer_length > 0) || buffer == NULL)
+       png_error(png_ptr, "No IDAT data (internal error)");
+ 
++#ifdef PNG_READ_APNG_SUPPORTED
++   /* If the app is not APNG-aware, decode only the first frame */
++   if (!(png_ptr->apng_flags & PNG_APNG_APP) && png_ptr->num_frames_read > 0)
++   {
++     png_ptr->flags |= PNG_FLAG_ZSTREAM_ENDED;
++     return;
++   }
++#endif
++
+    /* This routine must process all the data it has been given
+     * before returning, calling the row callback as required to
+     * handle the uncompressed results.
+@@ -1085,6 +1272,18 @@
+    png_set_read_fn(png_ptr, progressive_ptr, png_push_fill_buffer);
+ }
+ 
++#ifdef PNG_READ_APNG_SUPPORTED
++void PNGAPI
++png_set_progressive_frame_fn(png_structp png_ptr,
++   png_progressive_frame_ptr frame_info_fn,
++   png_progressive_frame_ptr frame_end_fn)
++{
++   png_ptr->frame_info_fn = frame_info_fn;
++   png_ptr->frame_end_fn = frame_end_fn;
++   png_ptr->apng_flags |= PNG_APNG_APP;
++}
++#endif
++
+ png_voidp PNGAPI
+ png_get_progressive_ptr(png_const_structrp png_ptr)
+ {
+diff -Naru libpng-1.6.40.org/pngpriv.h libpng-1.6.40/pngpriv.h
+--- libpng-1.6.40.org/pngpriv.h	2023-09-10 11:09:32.954139030 +0900
++++ libpng-1.6.40/pngpriv.h	2023-09-10 11:08:58.923075759 +0900
+@@ -628,6 +628,10 @@
+ #define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000U /* Have another chunk after IDAT */
+ #define PNG_WROTE_eXIf            0x4000U
+ #define PNG_IS_READ_STRUCT        0x8000U /* Else is a write struct */
++#ifdef PNG_APNG_SUPPORTED
++#define PNG_HAVE_acTL            0x10000U
++#define PNG_HAVE_fcTL            0x20000U
++#endif
+ 
+ /* Flags for the transformations the PNG library does on the image data */
+ #define PNG_BGR                 0x0001U
+@@ -864,6 +868,16 @@
+ #define png_tRNS PNG_U32(116,  82,  78,  83)
+ #define png_zTXt PNG_U32(122,  84,  88, 116)
+ 
++#ifdef PNG_APNG_SUPPORTED
++#define png_acTL PNG_U32( 97,  99,  84,  76)
++#define png_fcTL PNG_U32(102,  99,  84,  76)
++#define png_fdAT PNG_U32(102, 100,  65,  84)
++
++/* For png_struct.apng_flags: */
++#define PNG_FIRST_FRAME_HIDDEN       0x0001U
++#define PNG_APNG_APP                 0x0002U
++#endif
++
+ /* The following will work on (signed char*) strings, whereas the get_uint_32
+  * macro will fail on top-bit-set values because of the sign extension.
+  */
+@@ -1635,6 +1649,47 @@
+     */
+ #endif
+ 
++#ifdef PNG_APNG_SUPPORTED
++PNG_INTERNAL_FUNCTION(void,png_ensure_fcTL_is_valid,(png_structp png_ptr,
++   png_uint_32 width, png_uint_32 height,
++   png_uint_32 x_offset, png_uint_32 y_offset,
++   png_uint_16 delay_num, png_uint_16 delay_den,
++   png_byte dispose_op, png_byte blend_op), PNG_EMPTY);
++
++#ifdef PNG_READ_APNG_SUPPORTED
++PNG_INTERNAL_FUNCTION(void,png_handle_acTL,(png_structp png_ptr, png_infop info_ptr,
++   png_uint_32 length),PNG_EMPTY);
++PNG_INTERNAL_FUNCTION(void,png_handle_fcTL,(png_structp png_ptr, png_infop info_ptr,
++   png_uint_32 length),PNG_EMPTY);
++PNG_INTERNAL_FUNCTION(void,png_handle_fdAT,(png_structp png_ptr, png_infop info_ptr,
++   png_uint_32 length),PNG_EMPTY);
++PNG_INTERNAL_FUNCTION(void,png_have_info,(png_structp png_ptr, png_infop info_ptr),PNG_EMPTY);
++PNG_INTERNAL_FUNCTION(void,png_ensure_sequence_number,(png_structp png_ptr,
++   png_uint_32 length),PNG_EMPTY);
++PNG_INTERNAL_FUNCTION(void,png_read_reset,(png_structp png_ptr),PNG_EMPTY);
++PNG_INTERNAL_FUNCTION(void,png_read_reinit,(png_structp png_ptr,
++   png_infop info_ptr),PNG_EMPTY);
++#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
++PNG_INTERNAL_FUNCTION(void,png_progressive_read_reset,(png_structp png_ptr),PNG_EMPTY);
++#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
++#endif /* PNG_READ_APNG_SUPPORTED */
++
++#ifdef PNG_WRITE_APNG_SUPPORTED
++PNG_INTERNAL_FUNCTION(void,png_write_acTL,(png_structp png_ptr,
++   png_uint_32 num_frames, png_uint_32 num_plays),PNG_EMPTY);
++PNG_INTERNAL_FUNCTION(void,png_write_fcTL,(png_structp png_ptr,
++   png_uint_32 width, png_uint_32 height,
++   png_uint_32 x_offset, png_uint_32 y_offset,
++   png_uint_16 delay_num, png_uint_16 delay_den,
++   png_byte dispose_op, png_byte blend_op),PNG_EMPTY);
++PNG_INTERNAL_FUNCTION(void,png_write_fdAT,(png_structp png_ptr,
++   png_const_bytep data, png_size_t length),PNG_EMPTY);
++PNG_INTERNAL_FUNCTION(void,png_write_reset,(png_structp png_ptr),PNG_EMPTY);
++PNG_INTERNAL_FUNCTION(void,png_write_reinit,(png_structp png_ptr,
++   png_infop info_ptr, png_uint_32 width, png_uint_32 height),PNG_EMPTY);
++#endif /* PNG_WRITE_APNG_SUPPORTED */
++#endif /* PNG_APNG_SUPPORTED */
++
+ /* Added at libpng version 1.4.0 */
+ #ifdef PNG_COLORSPACE_SUPPORTED
+ /* These internal functions are for maintaining the colorspace structure within
+diff -Naru libpng-1.6.40.org/pngread.c libpng-1.6.40/pngread.c
+--- libpng-1.6.40.org/pngread.c	2022-11-24 08:37:51.508052181 +0900
++++ libpng-1.6.40/pngread.c	2023-09-10 11:08:58.923075759 +0900
+@@ -161,6 +161,9 @@
+ 
+       else if (chunk_name == png_IDAT)
+       {
++#ifdef PNG_READ_APNG_SUPPORTED
++         png_have_info(png_ptr, info_ptr);
++#endif
+          png_ptr->idat_size = length;
+          break;
+       }
+@@ -255,6 +258,17 @@
+          png_handle_iTXt(png_ptr, info_ptr, length);
+ #endif
+ 
++#ifdef PNG_READ_APNG_SUPPORTED
++      else if (chunk_name == png_acTL)
++         png_handle_acTL(png_ptr, info_ptr, length);
++
++      else if (chunk_name == png_fcTL)
++         png_handle_fcTL(png_ptr, info_ptr, length);
++
++      else if (chunk_name == png_fdAT)
++         png_handle_fdAT(png_ptr, info_ptr, length);
++#endif
++
+       else
+          png_handle_unknown(png_ptr, info_ptr, length,
+              PNG_HANDLE_CHUNK_AS_DEFAULT);
+@@ -262,6 +276,72 @@
+ }
+ #endif /* SEQUENTIAL_READ */
+ 
++#ifdef PNG_READ_APNG_SUPPORTED
++void PNGAPI
++png_read_frame_head(png_structp png_ptr, png_infop info_ptr)
++{
++    png_byte have_chunk_after_DAT; /* after IDAT or after fdAT */
++
++    png_debug(0, "Reading frame head");
++
++    if (!(png_ptr->mode & PNG_HAVE_acTL))
++        png_error(png_ptr, "attempt to png_read_frame_head() but "
++                           "no acTL present");
++
++    /* do nothing for the main IDAT */
++    if (png_ptr->num_frames_read == 0)
++        return;
++
++    png_read_reset(png_ptr);
++    png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
++    png_ptr->mode &= ~PNG_HAVE_fcTL;
++
++    have_chunk_after_DAT = 0;
++    for (;;)
++    {
++        png_uint_32 length = png_read_chunk_header(png_ptr);
++
++        if (png_ptr->chunk_name == png_IDAT)
++        {
++            /* discard trailing IDATs for the first frame */
++            if (have_chunk_after_DAT || png_ptr->num_frames_read > 1)
++                png_error(png_ptr, "png_read_frame_head(): out of place IDAT");
++            png_crc_finish(png_ptr, length);
++        }
++
++        else if (png_ptr->chunk_name == png_fcTL)
++        {
++            png_handle_fcTL(png_ptr, info_ptr, length);
++            have_chunk_after_DAT = 1;
++        }
++
++        else if (png_ptr->chunk_name == png_fdAT)
++        {
++            png_ensure_sequence_number(png_ptr, length);
++
++            /* discard trailing fdATs for frames other than the first */
++            if (!have_chunk_after_DAT && png_ptr->num_frames_read > 1)
++                png_crc_finish(png_ptr, length - 4);
++            else if(png_ptr->mode & PNG_HAVE_fcTL)
++            {
++                png_ptr->idat_size = length - 4;
++                png_ptr->mode |= PNG_HAVE_IDAT;
++
++                break;
++            }
++            else
++                png_error(png_ptr, "png_read_frame_head(): out of place fdAT");
++        }
++        else
++        {
++            png_warning(png_ptr, "Skipped (ignored) a chunk "
++                                 "between APNG chunks");
++            png_crc_finish(png_ptr, length);
++        }
++    }
++}
++#endif /* PNG_READ_APNG_SUPPORTED */
++
+ /* Optional call to update the users info_ptr structure */
+ void PNGAPI
+ png_read_update_info(png_structrp png_ptr, png_inforp info_ptr)
+diff -Naru libpng-1.6.40.org/pngrutil.c libpng-1.6.40/pngrutil.c
+--- libpng-1.6.40.org/pngrutil.c	2022-11-24 08:37:51.510052177 +0900
++++ libpng-1.6.40/pngrutil.c	2023-09-10 11:08:58.923075759 +0900
+@@ -864,6 +864,11 @@
+    filter_type = buf[11];
+    interlace_type = buf[12];
+ 
++#ifdef PNG_READ_APNG_SUPPORTED
++   png_ptr->first_frame_width = width;
++   png_ptr->first_frame_height = height;
++#endif
++
+    /* Set internal variables */
+    png_ptr->width = width;
+    png_ptr->height = height;
+@@ -2858,6 +2863,179 @@
+ }
+ #endif
+ 
++#ifdef PNG_READ_APNG_SUPPORTED
++void /* PRIVATE */
++png_handle_acTL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
++{
++    png_byte data[8];
++    png_uint_32 num_frames;
++    png_uint_32 num_plays;
++    png_uint_32 didSet;
++
++    png_debug(1, "in png_handle_acTL");
++
++    if (!(png_ptr->mode & PNG_HAVE_IHDR))
++    {
++        png_error(png_ptr, "Missing IHDR before acTL");
++    }
++    else if (png_ptr->mode & PNG_HAVE_IDAT)
++    {
++        png_warning(png_ptr, "Invalid acTL after IDAT skipped");
++        png_crc_finish(png_ptr, length);
++        return;
++    }
++    else if (png_ptr->mode & PNG_HAVE_acTL)
++    {
++        png_warning(png_ptr, "Duplicate acTL skipped");
++        png_crc_finish(png_ptr, length);
++        return;
++    }
++    else if (length != 8)
++    {
++        png_warning(png_ptr, "acTL with invalid length skipped");
++        png_crc_finish(png_ptr, length);
++        return;
++    }
++
++    png_crc_read(png_ptr, data, 8);
++    png_crc_finish(png_ptr, 0);
++
++    num_frames = png_get_uint_31(png_ptr, data);
++    num_plays = png_get_uint_31(png_ptr, data + 4);
++
++    /* the set function will do error checking on num_frames */
++    didSet = png_set_acTL(png_ptr, info_ptr, num_frames, num_plays);
++    if(didSet)
++        png_ptr->mode |= PNG_HAVE_acTL;
++}
++
++void /* PRIVATE */
++png_handle_fcTL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
++{
++    png_byte data[22];
++    png_uint_32 width;
++    png_uint_32 height;
++    png_uint_32 x_offset;
++    png_uint_32 y_offset;
++    png_uint_16 delay_num;
++    png_uint_16 delay_den;
++    png_byte dispose_op;
++    png_byte blend_op;
++
++    png_debug(1, "in png_handle_fcTL");
++
++    png_ensure_sequence_number(png_ptr, length);
++
++    if (!(png_ptr->mode & PNG_HAVE_IHDR))
++    {
++        png_error(png_ptr, "Missing IHDR before fcTL");
++    }
++    else if (png_ptr->mode & PNG_HAVE_IDAT)
++    {
++        /* for any frames other then the first this message may be misleading,
++        * but correct. PNG_HAVE_IDAT is unset before the frame head is read
++        * i can't think of a better message */
++        png_warning(png_ptr, "Invalid fcTL after IDAT skipped");
++        png_crc_finish(png_ptr, length-4);
++        return;
++    }
++    else if (png_ptr->mode & PNG_HAVE_fcTL)
++    {
++        png_warning(png_ptr, "Duplicate fcTL within one frame skipped");
++        png_crc_finish(png_ptr, length-4);
++        return;
++    }
++    else if (length != 26)
++    {
++        png_warning(png_ptr, "fcTL with invalid length skipped");
++        png_crc_finish(png_ptr, length-4);
++        return;
++    }
++
++    png_crc_read(png_ptr, data, 22);
++    png_crc_finish(png_ptr, 0);
++
++    width = png_get_uint_31(png_ptr, data);
++    height = png_get_uint_31(png_ptr, data + 4);
++    x_offset = png_get_uint_31(png_ptr, data + 8);
++    y_offset = png_get_uint_31(png_ptr, data + 12);
++    delay_num = png_get_uint_16(data + 16);
++    delay_den = png_get_uint_16(data + 18);
++    dispose_op = data[20];
++    blend_op = data[21];
++
++    if (png_ptr->num_frames_read == 0 && (x_offset != 0 || y_offset != 0))
++    {
++        png_warning(png_ptr, "fcTL for the first frame must have zero offset");
++        return;
++    }
++
++    if (info_ptr != NULL)
++    {
++        if (png_ptr->num_frames_read == 0 &&
++            (width != info_ptr->width || height != info_ptr->height))
++        {
++            png_warning(png_ptr, "size in first frame's fcTL must match "
++                               "the size in IHDR");
++            return;
++        }
++
++        /* The set function will do more error checking */
++        png_set_next_frame_fcTL(png_ptr, info_ptr, width, height,
++                                x_offset, y_offset, delay_num, delay_den,
++                                dispose_op, blend_op);
++
++        png_read_reinit(png_ptr, info_ptr);
++
++        png_ptr->mode |= PNG_HAVE_fcTL;
++    }
++}
++
++void /* PRIVATE */
++png_have_info(png_structp png_ptr, png_infop info_ptr)
++{
++    if((info_ptr->valid & PNG_INFO_acTL) && !(info_ptr->valid & PNG_INFO_fcTL))
++    {
++        png_ptr->apng_flags |= PNG_FIRST_FRAME_HIDDEN;
++        info_ptr->num_frames++;
++    }
++}
++
++void /* PRIVATE */
++png_handle_fdAT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
++{
++    png_ensure_sequence_number(png_ptr, length);
++
++    /* This function is only called from png_read_end(), png_read_info(),
++    * and png_push_read_chunk() which means that:
++    * - the user doesn't want to read this frame
++    * - or this is an out-of-place fdAT
++    * in either case it is safe to ignore the chunk with a warning */
++    png_warning(png_ptr, "ignoring fdAT chunk");
++    png_crc_finish(png_ptr, length - 4);
++    PNG_UNUSED(info_ptr)
++}
++
++void /* PRIVATE */
++png_ensure_sequence_number(png_structp png_ptr, png_uint_32 length)
++{
++    png_byte data[4];
++    png_uint_32 sequence_number;
++
++    if (length < 4)
++        png_error(png_ptr, "invalid fcTL or fdAT chunk found");
++
++    png_crc_read(png_ptr, data, 4);
++    sequence_number = png_get_uint_31(png_ptr, data);
++
++    if (sequence_number != png_ptr->next_seq_num)
++        png_error(png_ptr, "fcTL or fdAT chunk with out-of-order sequence "
++                           "number found");
++
++    png_ptr->next_seq_num++;
++}
++#endif /* PNG_READ_APNG_SUPPORTED */
++
+ #ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
+ /* Utility function for png_handle_unknown; set up png_ptr::unknown_chunk */
+ static int
+@@ -4166,7 +4344,38 @@
+       {
+          uInt avail_in;
+          png_bytep buffer;
++#ifdef PNG_READ_APNG_SUPPORTED
++         png_uint_32 bytes_to_skip = 0;
++
++         while (png_ptr->idat_size == 0 || bytes_to_skip != 0)
++         {
++            png_crc_finish(png_ptr, bytes_to_skip);
++            bytes_to_skip = 0;
+ 
++            png_ptr->idat_size = png_read_chunk_header(png_ptr);
++            if (png_ptr->num_frames_read == 0)
++            {
++               if (png_ptr->chunk_name != png_IDAT)
++                  png_error(png_ptr, "Not enough image data");
++            }
++            else
++            {
++               if (png_ptr->chunk_name == png_IEND)
++                  png_error(png_ptr, "Not enough image data");
++               if (png_ptr->chunk_name != png_fdAT)
++               {
++                  png_warning(png_ptr, "Skipped (ignored) a chunk "
++                                       "between APNG chunks");
++                  bytes_to_skip = png_ptr->idat_size;
++                  continue;
++               }
++
++               png_ensure_sequence_number(png_ptr, png_ptr->idat_size);
++
++               png_ptr->idat_size -= 4;
++            }
++         }
++#else
+          while (png_ptr->idat_size == 0)
+          {
+             png_crc_finish(png_ptr, 0);
+@@ -4178,7 +4387,7 @@
+             if (png_ptr->chunk_name != png_IDAT)
+                png_error(png_ptr, "Not enough image data");
+          }
+-
++#endif /* PNG_READ_APNG_SUPPORTED */
+          avail_in = png_ptr->IDAT_read_size;
+ 
+          if (avail_in > png_ptr->idat_size)
+@@ -4241,6 +4450,9 @@
+ 
+          png_ptr->mode |= PNG_AFTER_IDAT;
+          png_ptr->flags |= PNG_FLAG_ZSTREAM_ENDED;
++#ifdef PNG_READ_APNG_SUPPORTED
++         png_ptr->num_frames_read++;
++#endif
+ 
+          if (png_ptr->zstream.avail_in > 0 || png_ptr->idat_size > 0)
+             png_chunk_benign_error(png_ptr, "Extra compressed data");
+@@ -4678,4 +4890,80 @@
+ 
+    png_ptr->flags |= PNG_FLAG_ROW_INIT;
+ }
++
++#ifdef PNG_READ_APNG_SUPPORTED
++/* This function is to be called after the main IDAT set has been read and
++ * before a new IDAT is read. It resets some parts of png_ptr
++ * to make them usable by the read functions again */
++void /* PRIVATE */
++png_read_reset(png_structp png_ptr)
++{
++    png_ptr->mode &= ~PNG_HAVE_IDAT;
++    png_ptr->mode &= ~PNG_AFTER_IDAT;
++    png_ptr->row_number = 0;
++    png_ptr->pass = 0;
++}
++
++void /* PRIVATE */
++png_read_reinit(png_structp png_ptr, png_infop info_ptr)
++{
++    png_ptr->width = info_ptr->next_frame_width;
++    png_ptr->height = info_ptr->next_frame_height;
++    png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth,png_ptr->width);
++    png_ptr->info_rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth,
++        png_ptr->width);
++    if (png_ptr->prev_row)
++        memset(png_ptr->prev_row, 0, png_ptr->rowbytes + 1);
++}
++
++#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
++/* same as png_read_reset() but for the progressive reader */
++void /* PRIVATE */
++png_progressive_read_reset(png_structp png_ptr)
++{
++#ifdef PNG_READ_INTERLACING_SUPPORTED
++   /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */
++
++   /* Start of interlace block */
++    const int png_pass_start[] = {0, 4, 0, 2, 0, 1, 0};
++
++    /* Offset to next interlace block */
++    const int png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1};
++
++    /* Start of interlace block in the y direction */
++    const int png_pass_ystart[] = {0, 0, 4, 0, 2, 0, 1};
++
++    /* Offset to next interlace block in the y direction */
++    const int png_pass_yinc[] = {8, 8, 8, 4, 4, 2, 2};
++
++    if (png_ptr->interlaced)
++    {
++        if (!(png_ptr->transformations & PNG_INTERLACE))
++            png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 -
++                                png_pass_ystart[0]) / png_pass_yinc[0];
++        else
++            png_ptr->num_rows = png_ptr->height;
++
++        png_ptr->iwidth = (png_ptr->width +
++                           png_pass_inc[png_ptr->pass] - 1 -
++                           png_pass_start[png_ptr->pass]) /
++                           png_pass_inc[png_ptr->pass];
++    }
++    else
++#endif /* PNG_READ_INTERLACING_SUPPORTED */
++    {
++        png_ptr->num_rows = png_ptr->height;
++        png_ptr->iwidth = png_ptr->width;
++    }
++    png_ptr->flags &= ~PNG_FLAG_ZSTREAM_ENDED;
++    if (inflateReset(&(png_ptr->zstream)) != Z_OK)
++        png_error(png_ptr, "inflateReset failed");
++    png_ptr->zstream.avail_in = 0;
++    png_ptr->zstream.next_in = 0;
++    png_ptr->zstream.next_out = png_ptr->row_buf;
++    png_ptr->zstream.avail_out = (uInt)PNG_ROWBYTES(png_ptr->pixel_depth,
++        png_ptr->iwidth) + 1;
++}
++#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
++#endif /* PNG_READ_APNG_SUPPORTED */
+ #endif /* READ */
+diff -Naru libpng-1.6.40.org/pngset.c libpng-1.6.40/pngset.c
+--- libpng-1.6.40.org/pngset.c	2023-09-10 11:09:32.954139030 +0900
++++ libpng-1.6.40/pngset.c	2023-09-10 11:08:58.932075775 +0900
+@@ -280,6 +280,11 @@
+    info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);
+ 
+    info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, width);
++
++#ifdef PNG_APNG_SUPPORTED
++   /* for non-animated png. this may be overwritten from an acTL chunk later */
++   info_ptr->num_frames = 1;
++#endif
+ }
+ 
+ #ifdef PNG_oFFs_SUPPORTED
+@@ -1149,6 +1154,147 @@
+ }
+ #endif /* sPLT */
+ 
++#ifdef PNG_APNG_SUPPORTED
++png_uint_32 PNGAPI
++png_set_acTL(png_structp png_ptr, png_infop info_ptr,
++    png_uint_32 num_frames, png_uint_32 num_plays)
++{
++    png_debug1(1, "in %s storage function", "acTL");
++
++    if (png_ptr == NULL || info_ptr == NULL)
++    {
++        png_warning(png_ptr,
++                    "Call to png_set_acTL() with NULL png_ptr "
++                    "or info_ptr ignored");
++        return (0);
++    }
++    if (num_frames == 0)
++    {
++        png_warning(png_ptr,
++                    "Ignoring attempt to set acTL with num_frames zero");
++        return (0);
++    }
++    if (num_frames > PNG_UINT_31_MAX)
++    {
++        png_warning(png_ptr,
++                    "Ignoring attempt to set acTL with num_frames > 2^31-1");
++        return (0);
++    }
++    if (num_plays > PNG_UINT_31_MAX)
++    {
++        png_warning(png_ptr,
++                    "Ignoring attempt to set acTL with num_plays "
++                    "> 2^31-1");
++        return (0);
++    }
++
++    info_ptr->num_frames = num_frames;
++    info_ptr->num_plays = num_plays;
++
++    info_ptr->valid |= PNG_INFO_acTL;
++
++    return (1);
++}
++
++/* delay_num and delay_den can hold any 16-bit values including zero */
++png_uint_32 PNGAPI
++png_set_next_frame_fcTL(png_structp png_ptr, png_infop info_ptr,
++    png_uint_32 width, png_uint_32 height,
++    png_uint_32 x_offset, png_uint_32 y_offset,
++    png_uint_16 delay_num, png_uint_16 delay_den,
++    png_byte dispose_op, png_byte blend_op)
++{
++    png_debug1(1, "in %s storage function", "fcTL");
++
++    if (png_ptr == NULL || info_ptr == NULL)
++    {
++        png_warning(png_ptr,
++                    "Call to png_set_fcTL() with NULL png_ptr or info_ptr "
++                    "ignored");
++        return (0);
++    }
++
++    png_ensure_fcTL_is_valid(png_ptr, width, height, x_offset, y_offset,
++                             delay_num, delay_den, dispose_op, blend_op);
++
++    if (blend_op == PNG_BLEND_OP_OVER)
++    {
++        if (!(png_ptr->color_type & PNG_COLOR_MASK_ALPHA) &&
++            !(png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)))
++        {
++          png_warning(png_ptr, "PNG_BLEND_OP_OVER is meaningless "
++                               "and wasteful for opaque images, ignored");
++          blend_op = PNG_BLEND_OP_SOURCE;
++        }
++    }
++
++    info_ptr->next_frame_width = width;
++    info_ptr->next_frame_height = height;
++    info_ptr->next_frame_x_offset = x_offset;
++    info_ptr->next_frame_y_offset = y_offset;
++    info_ptr->next_frame_delay_num = delay_num;
++    info_ptr->next_frame_delay_den = delay_den;
++    info_ptr->next_frame_dispose_op = dispose_op;
++    info_ptr->next_frame_blend_op = blend_op;
++
++    info_ptr->valid |= PNG_INFO_fcTL;
++
++    return (1);
++}
++
++void /* PRIVATE */
++png_ensure_fcTL_is_valid(png_structp png_ptr,
++    png_uint_32 width, png_uint_32 height,
++    png_uint_32 x_offset, png_uint_32 y_offset,
++    png_uint_16 delay_num, png_uint_16 delay_den,
++    png_byte dispose_op, png_byte blend_op)
++{
++    if (width == 0 || width > PNG_UINT_31_MAX)
++        png_error(png_ptr, "invalid width in fcTL (> 2^31-1)");
++    if (height == 0 || height > PNG_UINT_31_MAX)
++        png_error(png_ptr, "invalid height in fcTL (> 2^31-1)");
++    if (x_offset > PNG_UINT_31_MAX)
++        png_error(png_ptr, "invalid x_offset in fcTL (> 2^31-1)");
++    if (y_offset > PNG_UINT_31_MAX)
++        png_error(png_ptr, "invalid y_offset in fcTL (> 2^31-1)");
++    if (width + x_offset > png_ptr->first_frame_width ||
++        height + y_offset > png_ptr->first_frame_height)
++        png_error(png_ptr, "dimensions of a frame are greater than"
++                           "the ones in IHDR");
++
++    if (dispose_op != PNG_DISPOSE_OP_NONE &&
++        dispose_op != PNG_DISPOSE_OP_BACKGROUND &&
++        dispose_op != PNG_DISPOSE_OP_PREVIOUS)
++        png_error(png_ptr, "invalid dispose_op in fcTL");
++
++    if (blend_op != PNG_BLEND_OP_SOURCE &&
++        blend_op != PNG_BLEND_OP_OVER)
++        png_error(png_ptr, "invalid blend_op in fcTL");
++
++    PNG_UNUSED(delay_num)
++    PNG_UNUSED(delay_den)
++}
++
++png_uint_32 PNGAPI
++png_set_first_frame_is_hidden(png_structp png_ptr, png_infop info_ptr,
++                              png_byte is_hidden)
++{
++    png_debug(1, "in png_first_frame_is_hidden()");
++
++    if (png_ptr == NULL)
++        return 0;
++
++    if (is_hidden)
++        png_ptr->apng_flags |= PNG_FIRST_FRAME_HIDDEN;
++    else
++        png_ptr->apng_flags &= ~PNG_FIRST_FRAME_HIDDEN;
++
++    PNG_UNUSED(info_ptr)
++
++    return 1;
++}
++#endif /* PNG_APNG_SUPPORTED */
++
+ #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
+ static png_byte
+ check_location(png_const_structrp png_ptr, int location)
+diff -Naru libpng-1.6.40.org/pngstruct.h libpng-1.6.40/pngstruct.h
+--- libpng-1.6.40.org/pngstruct.h	2022-11-24 08:37:51.510052177 +0900
++++ libpng-1.6.40/pngstruct.h	2023-09-10 11:08:58.924075760 +0900
+@@ -399,6 +399,27 @@
+    png_byte filter_type;
+ #endif
+ 
++#ifdef PNG_APNG_SUPPORTED
++   png_uint_32 apng_flags;
++   png_uint_32 next_seq_num;         /* next fcTL/fdAT chunk sequence number */
++   png_uint_32 first_frame_width;
++   png_uint_32 first_frame_height;
++
++#ifdef PNG_READ_APNG_SUPPORTED
++   png_uint_32 num_frames_read;      /* incremented after all image data of */
++                                     /* a frame is read */
++#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
++   png_progressive_frame_ptr frame_info_fn; /* frame info read callback */
++   png_progressive_frame_ptr frame_end_fn;  /* frame data read callback */
++#endif
++#endif
++
++#ifdef PNG_WRITE_APNG_SUPPORTED
++   png_uint_32 num_frames_to_write;
++   png_uint_32 num_frames_written;
++#endif
++#endif /* PNG_APNG_SUPPORTED */
++
+ /* New members added in libpng-1.2.0 */
+ 
+ /* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */
+diff -Naru libpng-1.6.40.org/pngtest.c libpng-1.6.40/pngtest.c
+--- libpng-1.6.40.org/pngtest.c	2023-09-10 11:12:23.044481879 +0900
++++ libpng-1.6.40/pngtest.c	2023-09-10 11:08:58.924075760 +0900
+@@ -875,6 +875,10 @@
+    volatile int num_passes;
+    int pass;
+    int bit_depth, color_type;
++#ifdef PNG_APNG_SUPPORTED
++   png_uint_32 num_frames;
++   png_uint_32 num_plays;
++#endif
+ 
+    row_buf = NULL;
+    error_parameters.file_name = inname;
+@@ -1383,6 +1387,22 @@
+       }
+    }
+ #endif
++
++#ifdef PNG_APNG_SUPPORTED
++   if (png_get_valid(read_ptr, read_info_ptr, PNG_INFO_acTL))
++   {
++      if (png_get_acTL(read_ptr, read_info_ptr, &num_frames, &num_plays))
++      {
++         png_byte is_hidden;
++         pngtest_debug2("Handling acTL chunks (frames %ld, plays %ld)",
++                    num_frames, num_plays);
++         png_set_acTL(write_ptr, write_info_ptr, num_frames, num_plays);
++         is_hidden = png_get_first_frame_is_hidden(read_ptr, read_info_ptr);
++         png_set_first_frame_is_hidden(write_ptr, write_info_ptr, is_hidden);
++      }
++   }
++#endif
++
+ #ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
+    {
+       png_unknown_chunkp unknowns;
+@@ -1463,6 +1483,110 @@
+    t_misc += (t_stop - t_start);
+    t_start = t_stop;
+ #endif
++#ifdef PNG_APNG_SUPPORTED
++   if (png_get_valid(read_ptr, read_info_ptr, PNG_INFO_acTL))
++   {
++      png_uint_32 frame;
++      for (frame = 0; frame < num_frames; frame++)
++      {
++         png_uint_32 frame_width;
++         png_uint_32 frame_height;
++         png_uint_32 x_offset;
++         png_uint_32 y_offset;
++         png_uint_16 delay_num;
++         png_uint_16 delay_den;
++         png_byte dispose_op;
++         png_byte blend_op;
++         png_read_frame_head(read_ptr, read_info_ptr);
++         if (png_get_valid(read_ptr, read_info_ptr, PNG_INFO_fcTL))
++         {
++            png_get_next_frame_fcTL(read_ptr, read_info_ptr,
++                                    &frame_width, &frame_height,
++                                    &x_offset, &y_offset,
++                                    &delay_num, &delay_den,
++                                    &dispose_op, &blend_op);
++         }
++         else
++         {
++            frame_width = width;
++            frame_height = height;
++            x_offset = 0;
++            y_offset = 0;
++            delay_num = 1;
++            delay_den = 1;
++            dispose_op = PNG_DISPOSE_OP_NONE;
++            blend_op = PNG_BLEND_OP_SOURCE;
++         }
++#ifdef PNG_WRITE_APNG_SUPPORTED
++         png_write_frame_head(write_ptr, write_info_ptr, (png_bytepp)&row_buf,
++                              frame_width, frame_height,
++                              x_offset, y_offset,
++                              delay_num, delay_den,
++                              dispose_op, blend_op);
++#endif
++         for (pass = 0; pass < num_passes; pass++)
++         {
++#           ifdef calc_pass_height
++               png_uint_32 pass_height;
++
++               if (num_passes == 7) /* interlaced */
++               {
++                  if (PNG_PASS_COLS(frame_width, pass) > 0)
++                     pass_height = PNG_PASS_ROWS(frame_height, pass);
++
++                  else
++                     pass_height = 0;
++               }
++
++               else /* not interlaced */
++                  pass_height = frame_height;
++#           else
++#              define pass_height frame_height
++#           endif
++
++            pngtest_debug1("Writing row data for pass %d", pass);
++            for (y = 0; y < pass_height; y++)
++            {
++#ifndef SINGLE_ROWBUF_ALLOC
++               pngtest_debug2("Allocating row buffer (pass %d, y = %u)...", pass, y);
++
++               row_buf = (png_bytep)png_malloc(read_ptr,
++                  png_get_rowbytes(read_ptr, read_info_ptr));
++
++               pngtest_debug2("\t0x%08lx (%lu bytes)", (unsigned long)row_buf,
++                  (unsigned long)png_get_rowbytes(read_ptr, read_info_ptr));
++
++#endif /* !SINGLE_ROWBUF_ALLOC */
++               png_read_rows(read_ptr, (png_bytepp)&row_buf, NULL, 1);
++
++#ifdef PNG_WRITE_SUPPORTED
++#ifdef PNGTEST_TIMING
++               t_stop = (float)clock();
++               t_decode += (t_stop - t_start);
++               t_start = t_stop;
++#endif
++               png_write_rows(write_ptr, (png_bytepp)&row_buf, 1);
++#ifdef PNGTEST_TIMING
++               t_stop = (float)clock();
++               t_encode += (t_stop - t_start);
++               t_start = t_stop;
++#endif
++#endif /* PNG_WRITE_SUPPORTED */
++
++#ifndef SINGLE_ROWBUF_ALLOC
++               pngtest_debug2("Freeing row buffer (pass %d, y = %u)", pass, y);
++               png_free(read_ptr, row_buf);
++               row_buf = NULL;
++#endif /* !SINGLE_ROWBUF_ALLOC */
++            }
++         }
++#ifdef PNG_WRITE_APNG_SUPPORTED
++         png_write_frame_tail(write_ptr, write_info_ptr);
++#endif
++      }
++   }
++   else
++#endif
+    for (pass = 0; pass < num_passes; pass++)
+    {
+ #     ifdef calc_pass_height
+diff -Naru libpng-1.6.40.org/pngwrite.c libpng-1.6.40/pngwrite.c
+--- libpng-1.6.40.org/pngwrite.c	2023-09-10 11:09:32.955139032 +0900
++++ libpng-1.6.40/pngwrite.c	2023-09-10 11:08:58.924075760 +0900
+@@ -128,6 +128,10 @@
+        * the application continues writing the PNG.  So check the 'invalid'
+        * flag here too.
+        */
++#ifdef PNG_WRITE_APNG_SUPPORTED
++      if (info_ptr->valid & PNG_INFO_acTL)
++         png_write_acTL(png_ptr, info_ptr->num_frames, info_ptr->num_plays);
++#endif
+ #ifdef PNG_GAMMA_SUPPORTED
+ #  ifdef PNG_WRITE_gAMA_SUPPORTED
+       if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) == 0 &&
+@@ -373,6 +377,11 @@
+       png_benign_error(png_ptr, "Wrote palette index exceeding num_palette");
+ #endif
+ 
++#ifdef PNG_WRITE_APNG_SUPPORTED
++   if (png_ptr->num_frames_written != png_ptr->num_frames_to_write)
++      png_error(png_ptr, "Not enough frames written");
++#endif
++
+    /* See if user wants us to write information chunks */
+    if (info_ptr != NULL)
+    {
+@@ -1475,6 +1484,43 @@
+ }
+ #endif
+ 
++#ifdef PNG_WRITE_APNG_SUPPORTED
++void PNGAPI
++png_write_frame_head(png_structp png_ptr, png_infop info_ptr,
++    png_bytepp row_pointers, png_uint_32 width, png_uint_32 height,
++    png_uint_32 x_offset, png_uint_32 y_offset,
++    png_uint_16 delay_num, png_uint_16 delay_den, png_byte dispose_op,
++    png_byte blend_op)
++{
++    png_debug(1, "in png_write_frame_head");
++
++    /* there is a chance this has been set after png_write_info was called,
++    * so it would be set but not written. is there a way to be sure? */
++    if (!(info_ptr->valid & PNG_INFO_acTL))
++        png_error(png_ptr, "png_write_frame_head(): acTL not set");
++
++    png_write_reset(png_ptr);
++
++    png_write_reinit(png_ptr, info_ptr, width, height);
++
++    if ( !(png_ptr->num_frames_written == 0 &&
++           (png_ptr->apng_flags & PNG_FIRST_FRAME_HIDDEN) ) )
++        png_write_fcTL(png_ptr, width, height, x_offset, y_offset,
++                       delay_num, delay_den, dispose_op, blend_op);
++
++    PNG_UNUSED(row_pointers)
++}
++
++void PNGAPI
++png_write_frame_tail(png_structp png_ptr, png_infop info_ptr)
++{
++    png_debug(1, "in png_write_frame_tail");
++
++    png_ptr->num_frames_written++;
++
++    PNG_UNUSED(info_ptr)
++}
++#endif /* PNG_WRITE_APNG_SUPPORTED */
+ 
+ #ifdef PNG_SIMPLIFIED_WRITE_SUPPORTED
+ /* Initialize the write structure - general purpose utility. */
+diff -Naru libpng-1.6.40.org/pngwutil.c libpng-1.6.40/pngwutil.c
+--- libpng-1.6.40.org/pngwutil.c	2022-11-24 08:37:51.511052176 +0900
++++ libpng-1.6.40/pngwutil.c	2023-09-10 11:08:58.952075811 +0900
+@@ -821,6 +821,11 @@
+    /* Write the chunk */
+    png_write_complete_chunk(png_ptr, png_IHDR, buf, 13);
+ 
++#ifdef PNG_WRITE_APNG_SUPPORTED
++   png_ptr->first_frame_width = width;
++   png_ptr->first_frame_height = height;
++#endif
++
+    if ((png_ptr->do_filter) == PNG_NO_FILTERS)
+    {
+       if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE ||
+@@ -1002,8 +1007,17 @@
+                optimize_cmf(data, png_image_size(png_ptr));
+ #endif
+ 
+-         if (size > 0)
+-            png_write_complete_chunk(png_ptr, png_IDAT, data, size);
++            if (size > 0)
++#ifdef PNG_WRITE_APNG_SUPPORTED
++            {
++               if (png_ptr->num_frames_written == 0)
++#endif
++               png_write_complete_chunk(png_ptr, png_IDAT, data, size);
++#ifdef PNG_WRITE_APNG_SUPPORTED
++               else
++                  png_write_fdAT(png_ptr, data, size);
++            }
++#endif /* PNG_WRITE_APNG_SUPPORTED */
+          png_ptr->mode |= PNG_HAVE_IDAT;
+ 
+          png_ptr->zstream.next_out = data;
+@@ -1050,7 +1064,17 @@
+ #endif
+ 
+          if (size > 0)
++#ifdef PNG_WRITE_APNG_SUPPORTED
++         {
++            if (png_ptr->num_frames_written == 0)
++#endif
+             png_write_complete_chunk(png_ptr, png_IDAT, data, size);
++#ifdef PNG_WRITE_APNG_SUPPORTED
++            else
++               png_write_fdAT(png_ptr, data, size);
++         }
++#endif /* PNG_WRITE_APNG_SUPPORTED */
++
+          png_ptr->zstream.avail_out = 0;
+          png_ptr->zstream.next_out = NULL;
+          png_ptr->mode |= PNG_HAVE_IDAT | PNG_AFTER_IDAT;
+@@ -1885,6 +1909,82 @@
+ }
+ #endif
+ 
++#ifdef PNG_WRITE_APNG_SUPPORTED
++void /* PRIVATE */
++png_write_acTL(png_structp png_ptr,
++    png_uint_32 num_frames, png_uint_32 num_plays)
++{
++    png_byte buf[8];
++
++    png_debug(1, "in png_write_acTL");
++
++    png_ptr->num_frames_to_write = num_frames;
++
++    if (png_ptr->apng_flags & PNG_FIRST_FRAME_HIDDEN)
++        num_frames--;
++
++    png_save_uint_32(buf, num_frames);
++    png_save_uint_32(buf + 4, num_plays);
++
++    png_write_complete_chunk(png_ptr, png_acTL, buf, (png_size_t)8);
++}
++
++void /* PRIVATE */
++png_write_fcTL(png_structp png_ptr, png_uint_32 width, png_uint_32 height,
++    png_uint_32 x_offset, png_uint_32 y_offset,
++    png_uint_16 delay_num, png_uint_16 delay_den, png_byte dispose_op,
++    png_byte blend_op)
++{
++    png_byte buf[26];
++
++    png_debug(1, "in png_write_fcTL");
++
++    if (png_ptr->num_frames_written == 0 && (x_offset != 0 || y_offset != 0))
++        png_error(png_ptr, "x and/or y offset for the first frame aren't 0");
++    if (png_ptr->num_frames_written == 0 &&
++        (width != png_ptr->first_frame_width ||
++         height != png_ptr->first_frame_height))
++        png_error(png_ptr, "width and/or height in the first frame's fcTL "
++                           "don't match the ones in IHDR");
++
++    /* more error checking */
++    png_ensure_fcTL_is_valid(png_ptr, width, height, x_offset, y_offset,
++                             delay_num, delay_den, dispose_op, blend_op);
++
++    png_save_uint_32(buf, png_ptr->next_seq_num);
++    png_save_uint_32(buf + 4, width);
++    png_save_uint_32(buf + 8, height);
++    png_save_uint_32(buf + 12, x_offset);
++    png_save_uint_32(buf + 16, y_offset);
++    png_save_uint_16(buf + 20, delay_num);
++    png_save_uint_16(buf + 22, delay_den);
++    buf[24] = dispose_op;
++    buf[25] = blend_op;
++
++    png_write_complete_chunk(png_ptr, png_fcTL, buf, (png_size_t)26);
++
++    png_ptr->next_seq_num++;
++}
++
++void /* PRIVATE */
++png_write_fdAT(png_structp png_ptr,
++    png_const_bytep data, png_size_t length)
++{
++    png_byte buf[4];
++
++    png_write_chunk_header(png_ptr, png_fdAT, (png_uint_32)(4 + length));
++
++    png_save_uint_32(buf, png_ptr->next_seq_num);
++    png_write_chunk_data(png_ptr, buf, 4);
++
++    png_write_chunk_data(png_ptr, data, length);
++
++    png_write_chunk_end(png_ptr);
++
++    png_ptr->next_seq_num++;
++}
++#endif /* PNG_WRITE_APNG_SUPPORTED */
++
+ /* Initializes the row writing capability of libpng */
+ void /* PRIVATE */
+ png_write_start_row(png_structrp png_ptr)
+@@ -2778,4 +2878,39 @@
+    }
+ #endif /* WRITE_FLUSH */
+ }
++
++#ifdef PNG_WRITE_APNG_SUPPORTED
++void /* PRIVATE */
++png_write_reset(png_structp png_ptr)
++{
++    png_ptr->row_number = 0;
++    png_ptr->pass = 0;
++    png_ptr->mode &= ~PNG_HAVE_IDAT;
++}
++
++void /* PRIVATE */
++png_write_reinit(png_structp png_ptr, png_infop info_ptr,
++                 png_uint_32 width, png_uint_32 height)
++{
++    if (png_ptr->num_frames_written == 0 &&
++        (width != png_ptr->first_frame_width ||
++         height != png_ptr->first_frame_height))
++        png_error(png_ptr, "width and/or height in the first frame's fcTL "
++                           "don't match the ones in IHDR");
++    if (width > png_ptr->first_frame_width ||
++        height > png_ptr->first_frame_height)
++        png_error(png_ptr, "width and/or height for a frame greater than"
++                           "the ones in IHDR");
++
++    png_set_IHDR(png_ptr, info_ptr, width, height,
++                 info_ptr->bit_depth, info_ptr->color_type,
++                 info_ptr->interlace_type, info_ptr->compression_type,
++                 info_ptr->filter_type);
++
++    png_ptr->width = width;
++    png_ptr->height = height;
++    png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, width);
++    png_ptr->usr_width = png_ptr->width;
++}
++#endif /* PNG_WRITE_APNG_SUPPORTED */
+ #endif /* WRITE */
+diff -Naru libpng-1.6.40.org/scripts/symbols.def libpng-1.6.40/scripts/symbols.def
+--- libpng-1.6.40.org/scripts/symbols.def	2022-11-24 08:37:51.515052168 +0900
++++ libpng-1.6.40/scripts/symbols.def	2023-09-10 11:08:58.925075762 +0900
+@@ -253,3 +253,23 @@
+  png_set_eXIf @247
+  png_get_eXIf_1 @248
+  png_set_eXIf_1 @249
++ png_get_acTL @250
++ png_set_acTL @251
++ png_get_num_frames @252
++ png_get_num_plays @253
++ png_get_next_frame_fcTL @254
++ png_set_next_frame_fcTL @255
++ png_get_next_frame_width @256
++ png_get_next_frame_height @257
++ png_get_next_frame_x_offset @258
++ png_get_next_frame_y_offset @259
++ png_get_next_frame_delay_num @260
++ png_get_next_frame_delay_den @261
++ png_get_next_frame_dispose_op @262
++ png_get_next_frame_blend_op @263
++ png_get_first_frame_is_hidden @264
++ png_set_first_frame_is_hidden @265
++ png_read_frame_head @266
++ png_set_progressive_frame_fn @267
++ png_write_frame_head @268
++ png_write_frame_tail @269
diff --git a/thirdparty/openmpt_svn_version.h b/thirdparty/openmpt_svn_version.h
deleted file mode 100644
index a45ed9f22449e7a4164bd2a7881c5ae52f805087..0000000000000000000000000000000000000000
--- a/thirdparty/openmpt_svn_version.h
+++ /dev/null
@@ -1,10 +0,0 @@
-
-#pragma once
-#define OPENMPT_VERSION_SVNVERSION "17963"
-#define OPENMPT_VERSION_REVISION 17963
-#define OPENMPT_VERSION_DIRTY 0
-#define OPENMPT_VERSION_MIXEDREVISIONS 0
-#define OPENMPT_VERSION_URL "https://source.openmpt.org/svn/openmpt/tags/libopenmpt-0.4.32"
-#define OPENMPT_VERSION_DATE "2022-09-25T14:19:05.052596Z"
-#define OPENMPT_VERSION_IS_PACKAGE 1
-
diff --git a/thirdparty/sdl2-mixer-ext.cmake b/thirdparty/sdl2-mixer-ext.cmake
new file mode 100644
index 0000000000000000000000000000000000000000..a52b11584ae747630ed4c44af6282fb8cc9dea75
--- /dev/null
+++ b/thirdparty/sdl2-mixer-ext.cmake
@@ -0,0 +1,39 @@
+if(TARGET SDL2_mixer_ext_Static)
+    return()
+endif()
+
+message(STATUS "Third-party: creating target 'SDL2_mixer_ext::SDL2_mixer_ext'")
+
+set(SDL_MIXER_X_SHARED ${SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES} CACHE BOOL "" FORCE)
+set(SDL_MIXER_X_STATIC ${NOT_SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES} CACHE BOOL "" FORCE)
+set(SDL_MIXER_X_DISABLE_INSTALL ON CACHE BOOL "" FORCE)
+set(USE_SYSTEM_SDL2 ON CACHE BOOL "" FORCE)
+set(SDL2_INCLUDE_PATH ${SDL2_INCLUDE_DIR} CACHE PATH "" FORCE)
+set(USE_XMP OFF CACHE PATH "" FORCE)
+
+set(
+	internal_SDL2_mixer_ext_options
+		"SDL_MIXER_X_SHARED ${SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES}"
+		"SDL_MIXER_X_STATIC ${NOT_SRB2_CONFIG_SHARED_INTERNAL_LIBRARIES}"
+		"SDL_MIXER_X_DISABLE_INSTALL ON"
+		"USE_SYSTEM_SDL2 ON"
+		"USE_XMP OFF"
+)
+
+if(${CMAKE_SYSTEM} MATCHES Windows)
+	#list(APPEND internal_SDL2_mixer_ext_options "DOWNLOAD_AUDIO_CODECS_DEPENDENCY ON")
+	#set(DOWNLOAD_AUDIO_CODECS_DEPENDENCY ON CACHE BOOL "" FORCE)
+endif()
+
+include(FetchContent)
+
+
+FetchContent_Declare(
+	SDL2_mixer_ext
+	OPTIONS ${internal_SDL2_mixer_ext_options}
+	GIT_TAG "2.6.0-1"
+	GIT_REPOSITORY "https://github.com/STJr/SDL-Mixer-X.git"
+)
+
+FetchContent_MakeAvailable(SDL2_mixer_ext)
+
diff --git a/thirdparty/sdl2.cmake b/thirdparty/sdl2.cmake
new file mode 100644
index 0000000000000000000000000000000000000000..16fbd7563b2f1c57a12a9202c3e89a69a2f9c191
--- /dev/null
+++ b/thirdparty/sdl2.cmake
@@ -0,0 +1,61 @@
+if(TARGET SDL2-static)
+    return()
+endif()
+
+message(STATUS "Third-party: creating target 'SDL2::SDL2'")
+
+set(SDL_STATIC ON CACHE BOOL "" FORCE)
+set(SDL_SHARED OFF CACHE BOOL "" FORCE)
+set(SDL_TEST OFF CACHE BOOL "" FORCE)
+set(SDL2_DISABLE_INSTALL OFF CACHE BOOL "" FORCE)
+
+set(
+	internal_sdl2_options
+
+		"SDL_STATIC ON"
+		"SDL_SHARED OFF"
+		"SDL_TEST OFF"
+		"SDL2_DISABLE_INSTALL OFF"
+)
+
+if(${CMAKE_SYSTEM} MATCHES Windows)
+	list(APPEND internal_sdl2_options "SDL2_DISABLE_SDL2MAIN OFF")
+	option(SDL2_DISABLE_SDL2MAIN   "Disable building/installation of SDL2main" OFF)
+	set(SDL2_DISABLE_SDL2MAIN OFF CACHE BOOL "" FORCE)
+endif()
+if(${CMAKE_SYSTEM} MATCHES Darwin)
+	list(APPEND internal_sdl2_options "SDL2_DISABLE_SDL2MAIN OFF")
+	option(SDL2_DISABLE_SDL2MAIN   "Disable building/installation of SDL2main" OFF)
+	set(SDL2_DISABLE_SDL2MAIN OFF CACHE BOOL "" FORCE)
+endif()
+if(${CMAKE_SYSTEM} MATCHES Linux)
+	list(APPEND internal_sdl2_options "SDL2_DISABLE_SDL2MAIN ON")
+	option(SDL2_DISABLE_SDL2MAIN   "Disable building/installation of SDL2main" ON)
+	set(SDL2_DISABLE_SDL2MAIN ON CACHE BOOL "" FORCE)
+endif()
+
+include(FetchContent)
+
+if (SDL2_USE_THIRDPARTY)
+	FetchContent_Declare(
+		SDL2
+		VERSION 2.30.0
+		GITHUB_REPOSITORY "libsdl-org/SDL"
+		GIT_TAG release-2.30.0
+		OPTIONS ${internal_sdl2_options}
+		OVERRIDE_FIND_PACKAGE
+	)
+else()
+	FetchContent_Declare(
+		SDL2
+		SOURCE_DIR "${CMAKE_SOURCE_DIR}/thirdparty/SDL2/"
+		OPTIONS ${internal_sdl2_options}
+		OVERRIDE_FIND_PACKAGE
+	)
+endif()
+
+FetchContent_MakeAvailable(SDL2)
+
+set(SDL2_INCLUDE_DIR "${SDL2_BINARY_DIR}/include" CACHE PATH "" FORCE)
+set(SDL2_LIBRARY "${SDL2_BINARY_DIR}/SDL2-staticd.lib" CACHE PATH "" FORCE)
+set(SDL2_DIR ${SDL2_BINARY_DIR} CACHE PATH "" FORCE)
diff --git a/thirdparty/vcpkg-overlays/.placeholder b/thirdparty/vcpkg-overlays/.placeholder
new file mode 100644
index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391
diff --git a/thirdparty/zlib.cmake b/thirdparty/zlib.cmake
new file mode 100644
index 0000000000000000000000000000000000000000..257609f775ae9f7c325665198f0e8804a5cb6030
--- /dev/null
+++ b/thirdparty/zlib.cmake
@@ -0,0 +1,36 @@
+if(TARGET ZLIB::ZLIB)
+    return()
+endif()
+
+message(STATUS "Third-party: creating target 'ZLIB::ZLIB'")
+
+set(BUILD_SHARED_LIBS OFF CACHE BOOL "" FORCE)
+
+include(FetchContent)
+
+if (zlib_USE_THIRDPARTY)
+	FetchContent_Declare(
+		ZLIB
+		GITHUB_REPOSITORY "madler/zlib"
+		GIT_TAG v1.3.1
+		OVERRIDE_FIND_PACKAGE
+		OPTIONS
+			"ZLIB_BUILD_EXAMPLES OFF"
+	)
+else()
+	FetchContent_Declare(
+		ZLIB
+		SOURCE_DIR "${CMAKE_SOURCE_DIR}/thirdparty/zlib/"
+		OVERRIDE_FIND_PACKAGE
+		OPTIONS
+			"ZLIB_BUILD_EXAMPLES OFF"
+	)
+endif()
+
+FetchContent_MakeAvailable(ZLIB)
+
+
+add_library(ZLIB::ZLIB ALIAS zlibstatic)
+
+set(ZLIB_INCLUDE_DIRS "${CMAKE_CURRENT_SOURCE_DIR}/zlib" "${zlib_BINARY_DIR}" CACHE PATH "" FORCE)
+
diff --git a/vcpkg-configuration.json b/vcpkg-configuration.json
new file mode 100644
index 0000000000000000000000000000000000000000..547114800f3088a704ec397b482c4bfed86cea3d
--- /dev/null
+++ b/vcpkg-configuration.json
@@ -0,0 +1,6 @@
+{
+  "$schema": "https://raw.githubusercontent.com/microsoft/vcpkg-tool/main/docs/vcpkg-configuration.schema.json",
+  "overlay-ports": [
+    "./thirdparty/vcpkg-overlays"
+  ]
+}
diff --git a/vcpkg.json b/vcpkg.json
new file mode 100644
index 0000000000000000000000000000000000000000..07c4244ad3affde086c98bd46867ae8cd0d02b18
--- /dev/null
+++ b/vcpkg.json
@@ -0,0 +1,85 @@
+{
+  "$schema": "https://raw.githubusercontent.com/microsoft/vcpkg-tool/main/docs/vcpkg.schema.json",
+  "name": "srb2",
+  "version": "1.0.0",
+  "builtin-baseline": "c823fd3e57035b10d970a96da2796a2db55e5df5",
+  "dependencies": [
+    "curl",
+    {
+      "name": "libgme",
+      "platform": "!(windows & mingw) & !native"
+    },
+    {
+      "name": "libopenmpt",
+      "platform": "!(windows & mingw)"
+    },
+    "libpng",
+    "miniupnpc",
+    "sdl2",
+    {
+      "name": "sdl2-mixer-ext",
+      "features": [
+        {
+          "name": "cmd",
+          "platform": "linux"
+        },
+        {
+          "name": "libflac",
+          "platform": "!(windows & mingw & !static)"
+        },
+        {
+          "name": "libgme",
+          "platform": "!(windows & mingw) & !native"
+        },
+        {
+          "name": "libmodplug",
+          "platform": "!(windows & mingw)"
+        },
+        {
+          "name": "libopnmidi",
+          "platform": "!(windows & mingw)"
+        },
+        {
+          "name": "libvorbis",
+          "platform": "!(windows & mingw & !static)"
+        },
+        {
+          "name": "libxmp",
+          "platform": "!(windows & mingw)"
+        },
+        {
+          "name": "mpg123",
+          "platform": "!(windows & mingw)"
+        },
+        {
+          "name": "nativemidi",
+          "platform": "!(windows & mingw)"
+        },
+        {
+          "name": "opusfile",
+          "platform": "!(windows & mingw)"
+        },
+        {
+          "name": "pxtone",
+          "platform": "!(windows & mingw)"
+        },
+        {
+          "name": "timidity",
+          "platform": "!(windows & mingw)"
+        },
+        {
+          "name": "wavpack",
+          "platform": "!(windows & mingw)"
+        }
+      ]
+    },
+    "zlib"
+  ],
+  "overrides": [
+    {
+      "name": "sdl2",
+      "version": "2.28.5",
+      "port-version": 1
+    }
+  ]
+}