libs/FMOD.props

+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <ImportGroup Label="PropertySheets" />
+  <PropertyGroup Label="UserMacros" />
+  <PropertyGroup>
+    <IncludePath>$(SolutionDir)libs\fmodex\inc;$(IncludePath)</IncludePath>
+    <LibraryPath>$(SolutionDir)libs\fmodex\lib;$(LibraryPath)</LibraryPath>
+  </PropertyGroup>
+  <ItemDefinitionGroup />
+  <ItemDefinitionGroup Condition="'$(PlatformTarget)'=='x64'">
+    <Link>
+      <AdditionalDependencies>fmodexL64_vc.lib;%(AdditionalDependencies)</AdditionalDependencies>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(PlatformTarget)'=='x86'">
+    <Link>
+      <AdditionalDependencies>fmodexL_vc.lib;%(AdditionalDependencies)</AdditionalDependencies>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemGroup />
+</Project>
\ No newline at end of file

libs/SDL2.props

+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <ImportGroup Label="PropertySheets" />
+  <PropertyGroup Label="UserMacros" />
+  <PropertyGroup>
+    <IncludePath>$(SolutionDir)libs\SDL2\include;$(IncludePath)</IncludePath>
+    <LibraryPath>$(SolutionDir)libs\SDL2\lib\$(PlatformTarget);$(LibraryPath)</LibraryPath>
+  </PropertyGroup>
+  <ItemDefinitionGroup>
+    <Link>
+      <AdditionalDependencies>SDL2.lib;%(AdditionalDependencies)</AdditionalDependencies>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemGroup />
+</Project>
\ No newline at end of file

libs/SDL2/BUGS.txt

+
+Bugs are now managed in the SDL bug tracker, here:
+
+    https://bugzilla.libsdl.org/
+
+You may report bugs there, and search to see if a given issue has already
+ been reported, discussed, and maybe even fixed.
+
+
+You may also find help at the SDL forums/mailing list:
+
+    https://discourse.libsdl.org/
+
+Bug reports are welcome here, but we really appreciate if you use Bugzilla, as
+ bugs discussed on the mailing list may be forgotten or missed.
+

libs/SDL2/COPYING.txt

+
+Simple DirectMedia Layer
+Copyright (C) 1997-2019 Sam Lantinga <slouken@libsdl.org>
+  
+This software is provided 'as-is', without any express or implied
+warranty.  In no event will the authors be held liable for any damages
+arising from the use of this software.
+
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it
+freely, subject to the following restrictions:
+  
+1. The origin of this software must not be misrepresented; you must not
+   claim that you wrote the original software. If you use this software
+   in a product, an acknowledgment in the product documentation would be
+   appreciated but is not required. 
+2. Altered source versions must be plainly marked as such, and must not be
+   misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+

libs/SDL2/CREDITS.txt

+
+Simple DirectMedia Layer CREDITS
+Thanks to everyone who made this possible, including:
+
+* Cliff Matthews, for giving me a reason to start this project. :)
+ -- Executor rocks!  *grin*
+
+* Ryan Gordon for helping everybody out and keeping the dream alive. :)
+
+* Gabriel Jacobo for his work on the Android port and generally helping out all around.
+ 
+* Philipp Wiesemann for his attention to detail reviewing the entire SDL code base and proposes patches.
+
+* Andreas Schiffler for his dedication to unit tests, Visual Studio projects, and managing the Google Summer of Code.
+
+* Mike Sartain for incorporating SDL into Team Fortress 2 and cheering me on at Valve.
+
+* Alfred Reynolds for the game controller API and general (in)sanity
+
+* Jørgen Tjernø for numerous magical Mac OS X fixes.
+
+* Pierre-Loup Griffais for his deep knowledge of OpenGL drivers.
+ 
+* Julian Winter for the SDL 2.0 website.
+
+* Sheena Smith for many months of great work on the SDL wiki creating the API documentation and style guides.
+
+* Paul Hunkin for his port of SDL to Android during the Google Summer of Code 2010.
+
+* Eli Gottlieb for his work on shaped windows during the Google Summer of Code 2010.
+
+* Jim Grandpre for his work on multi-touch and gesture recognition during
+  the Google Summer of Code 2010.
+
+* Edgar "bobbens" Simo for his force feedback API development during the
+  Google Summer of Code 2008.
+
+* Aaron Wishnick for his work on audio resampling and pitch shifting during
+  the Google Summer of Code 2008.
+
+* Holmes Futrell for his port of SDL to the iPhone and iPod Touch during the
+  Google Summer of Code 2008.
+
+* Jon Atkins for SDL_image, SDL_mixer and SDL_net documentation.
+
+* Everybody at Loki Software, Inc. for their great contributions!
+
+ And a big hand to everyone else who has contributed over the years.
+
+THANKS! :)
+
+  -- Sam Lantinga			<slouken@libsdl.org>
+

libs/SDL2/INSTALL.txt

+
+The 32-bit files are in i686-w64-mingw32
+The 64-bit files are in x86_64-w64-mingw32
+
+To install SDL for native development:
+    make native
+
+To install SDL for cross-compiling development:
+    make cross
+
+Look at the example programs in ./test, and check out online documentation:
+    http://wiki.libsdl.org/
+
+Join the SDL developer mailing list if you want to join the community:
+    http://www.libsdl.org/mailing-list.php
+
+That's it!
+Sam Lantinga <slouken@libsdl.org>

libs/SDL2/Makefile

+#
+# Makefile for installing the mingw32 version of the SDL library
+
+CROSS_PATH := /usr/local
+ARCHITECTURES := i686-w64-mingw32 x86_64-w64-mingw32
+
+all install:
+	@echo "Type \"make native\" to install 32-bit to /usr"
+	@echo "Type \"make cross\" to install 32-bit and 64-bit to $(CROSS_PATH)"
+
+native:
+	make install-package arch=i686-w64-mingw32 prefix=/usr
+
+cross:
+	for arch in $(ARCHITECTURES); do \
+	    make install-package arch=$$arch prefix=$(CROSS_PATH)/$$arch; \
+	done
+
+install-package:
+	@if test -d $(arch) && test -d $(prefix); then \
+	    (cd $(arch) && cp -rv bin include lib share $(prefix)/); \
+	    sed "s|^prefix=.*|prefix=$(prefix)|" <$(arch)/bin/sdl2-config >$(prefix)/bin/sdl2-config; \
+	    chmod 755 $(prefix)/bin/sdl2-config; \
+	    sed "s|^libdir=.*|libdir=\'$(prefix)/lib\'|" <$(arch)/lib/libSDL2.la >$(prefix)/lib/libSDL2.la; \
+	    sed "s|^libdir=.*|libdir=\'$(prefix)/lib\'|" <$(arch)/lib/libSDL2main.la >$(prefix)/lib/libSDL2main.la; \
+	    sed "s|^prefix=.*|prefix=$(prefix)|" <$(arch)/lib/pkgconfig/sdl2.pc >$(prefix)/lib/pkgconfig/sdl2.pc; \
+	else \
+	    echo "*** ERROR: $(arch) or $(prefix) does not exist!"; \
+	    exit 1; \
+	fi

libs/SDL2/README-SDL.txt

+
+Please distribute this file with the SDL runtime environment:
+
+The Simple DirectMedia Layer (SDL for short) is a cross-platform library
+designed to make it easy to write multi-media software, such as games
+and emulators.
+
+The Simple DirectMedia Layer library source code is available from:
+https://www.libsdl.org/
+
+This library is distributed under the terms of the zlib license:
+http://www.zlib.net/zlib_license.html
+

libs/SDL2/README.txt

+
+                         Simple DirectMedia Layer
+
+                                  (SDL)
+
+                                Version 2.0
+
+---
+https://www.libsdl.org/
+
+Simple DirectMedia Layer is a cross-platform development library designed
+to provide low level access to audio, keyboard, mouse, joystick, and graphics
+hardware via OpenGL and Direct3D. It is used by video playback software,
+emulators, and popular games including Valve's award winning catalog
+and many Humble Bundle games.
+
+More extensive documentation is available in the docs directory, starting
+with README.md
+
+Enjoy!
+	Sam Lantinga				(slouken@libsdl.org)

libs/SDL2/SRB2NOTE.txt

+# SDL Development Libaries
+
+Download both the VC and MinGW packages and extract them here.
+
+https://www.libsdl.org/download-2.0.php
+
+## VC Package
+
+* include
+* lib
+
+## MinGW Package
+
+* i686-w64-mingw32
+* x86_64-w64-mingw32

libs/SDL2/WhatsNew.txt

+
+This is a list of major changes in SDL's version history.
+
+---------------------------------------------------------------------------
+2.0.10:
+---------------------------------------------------------------------------
+
+General:
+* The SDL_RW* macros have been turned into functions that are available only in 2.0.10 and onward
+* Added SDL_SIMDGetAlignment(), SDL_SIMDAlloc(), and SDL_SIMDFree(), to allocate memory aligned for SIMD operations for the current CPU
+* Added SDL_RenderDrawPointF(), SDL_RenderDrawPointsF(), SDL_RenderDrawLineF(), SDL_RenderDrawLinesF(), SDL_RenderDrawRectF(), SDL_RenderDrawRectsF(), SDL_RenderFillRectF(), SDL_RenderFillRectsF(), SDL_RenderCopyF(), SDL_RenderCopyExF(), to allow floating point precision in the SDL rendering API.
+* Added SDL_GetTouchDeviceType() to get the type of a touch device, which can be a touch screen or a trackpad in relative or absolute coordinate mode.
+* The SDL rendering API now uses batched rendering by default, for improved performance
+* Added SDL_RenderFlush() to force batched render commands to execute, if you're going to mix SDL rendering with native rendering
+* Added the hint SDL_HINT_RENDER_BATCHING to control whether batching should be used for the rendering API. This defaults to "1" if you don't specify what rendering driver to use when creating the renderer.
+* Added the hint SDL_HINT_EVENT_LOGGING to enable logging of SDL events for debugging purposes
+* Added the hint SDL_HINT_GAMECONTROLLERCONFIG_FILE to specify a file that will be loaded at joystick initialization with game controller bindings
+* Added the hint SDL_HINT_MOUSE_TOUCH_EVENTS to control whether SDL will synthesize touch events from mouse events
+* Improved handling of malformed WAVE and BMP files, fixing potential security exploits
+
+Linux:
+* Removed the Mir video driver in favor of Wayland
+
+iOS / tvOS:
+* Added support for Xbox and PS4 wireless controllers in iOS 13 and tvOS 13
+* Added support for text input using Bluetooth keyboards
+
+Android:
+* Added low latency audio using OpenSL ES
+* Removed SDL_HINT_ANDROID_SEPARATE_MOUSE_AND_TOUCH (replaced by SDL_HINT_MOUSE_TOUCH_EVENTS and SDL_HINT_TOUCH_MOUSE_EVENTS)
+  SDL_HINT_ANDROID_SEPARATE_MOUSE_AND_TOUCH=1, should be replaced by setting both previous hints to 0.
+  SDL_HINT_ANDROID_SEPARATE_MOUSE_AND_TOUCH=0, should be replaced by setting both previous hints to 1.
+* Added the hint SDL_HINT_ANDROID_BLOCK_ON_PAUSE to set whether the event loop will block itself when the app is paused.
+
+
+---------------------------------------------------------------------------
+2.0.9:
+---------------------------------------------------------------------------
+
+General:
+* Added a new sensor API, initialized by passing SDL_INIT_SENSOR to SDL_Init(), and defined in SDL_sensor.h
+* Added an event SDL_SENSORUPDATE which is sent when a sensor is updated
+* Added SDL_GetDisplayOrientation() to return the current display orientation
+* Added an event SDL_DISPLAYEVENT which is sent when the display orientation changes
+* Added HIDAPI joystick drivers for more consistent support for Xbox, PS4 and Nintendo Switch Pro controller support across platforms. (Thanks to Valve for contributing the PS4 and Nintendo Switch Pro controller support)
+* Added support for many other popular game controllers
+* Added SDL_JoystickGetDevicePlayerIndex(), SDL_JoystickGetPlayerIndex(), and SDL_GameControllerGetPlayerIndex() to get the player index for a controller. For XInput controllers this returns the XInput index for the controller.
+* Added SDL_GameControllerRumble() and SDL_JoystickRumble() which allow simple rumble without using the haptics API
+* Added SDL_GameControllerMappingForDeviceIndex() to get the mapping for a controller before it's opened
+* Added the hint SDL_HINT_MOUSE_DOUBLE_CLICK_TIME to control the mouse double-click time
+* Added the hint SDL_HINT_MOUSE_DOUBLE_CLICK_RADIUS to control the mouse double-click radius, in pixels
+* Added SDL_HasColorKey() to return whether a surface has a colorkey active
+* Added SDL_HasAVX512F() to return whether the CPU has AVX-512F features
+* Added SDL_IsTablet() to return whether the application is running on a tablet
+* Added SDL_THREAD_PRIORITY_TIME_CRITICAL for threads that must run at the highest priority
+
+Mac OS X:
+* Fixed black screen at start on Mac OS X Mojave
+
+Linux:
+* Added SDL_LinuxSetThreadPriority() to allow adjusting the thread priority of native threads using RealtimeKit if available.
+
+iOS:
+* Fixed Asian IME input
+
+Android:
+* Updated required Android SDK to API 26, to match Google's new App Store requirements
+* Added support for wired USB Xbox, PS4, and Nintendo Switch Pro controllers
+* Added support for relative mouse mode on Android 7.0 and newer (except where it's broken, on Chromebooks and when in DeX mode with Samsung Experience 9.0)
+* Added support for custom mouse cursors on Android 7.0 and newer
+* Added the hint SDL_HINT_ANDROID_TRAP_BACK_BUTTON to control whether the back button will back out of the app (the default) or be passed to the application as SDL_SCANCODE_AC_BACK
+* Added SDL_AndroidBackButton() to trigger the Android system back button behavior when handling the back button in the application
+* Added SDL_IsChromebook() to return whether the app is running in the Chromebook Android runtime
+* Added SDL_IsDeXMode() to return whether the app is running while docked in the Samsung DeX
+
+
+---------------------------------------------------------------------------
+2.0.8:
+---------------------------------------------------------------------------
+
+General:
+* Added SDL_fmod() and SDL_log10()
+* Each of the SDL math functions now has the corresponding float version
+* Added SDL_SetYUVConversionMode() and SDL_GetYUVConversionMode() to control the formula used when converting to and from YUV colorspace. The options are JPEG, BT.601, and BT.709
+
+Windows:
+* Implemented WASAPI support on Windows UWP and removed the deprecated XAudio2 implementation
+* Added resampling support on WASAPI on Windows 7 and above
+
+Windows UWP:
+* Added SDL_WinRTGetDeviceFamily() to find out what type of device your application is running on
+
+Mac OS X:
+* Added support for the Vulkan SDK for Mac:
+  https://www.lunarg.com/lunarg-releases-vulkan-sdk-1-0-69-0-for-mac/
+* Added support for OpenGL ES using ANGLE when it's available
+
+Mac OS X / iOS / tvOS:
+* Added a Metal 2D render implementation
+* Added SDL_RenderGetMetalLayer() and SDL_RenderGetMetalCommandEncoder() to insert your own drawing into SDL rendering when using the Metal implementation
+
+iOS:
+* Added the hint SDL_HINT_IOS_HIDE_HOME_INDICATOR to control whether the home indicator bar on iPhone X should be hidden. This defaults to dimming the indicator for fullscreen applications and showing the indicator for windowed applications.
+
+iOS / Android:
+* Added the hint SDL_HINT_RETURN_KEY_HIDES_IME to control whether the return key on the software keyboard should hide the keyboard or send a key event (the default)
+
+Android:
+* SDL now supports building with Android Studio and Gradle by default, and the old Ant project is available in android-project-ant
+* SDL now requires the API 19 SDK to build, but can still target devices down to API 14 (Android 4.0.1)
+* Added SDL_IsAndroidTV() to tell whether the application is running on Android TV
+
+Android / tvOS:
+* Added the hint SDL_HINT_TV_REMOTE_AS_JOYSTICK to control whether TV remotes should be listed as joystick devices (the default) or send keyboard events.
+
+Linux:
+* Added the hint SDL_HINT_VIDEO_X11_NET_WM_BYPASS_COMPOSITOR to control whether the X server should skip the compositor for the SDL application. This defaults to "1"
+* Added the hint SDL_HINT_VIDEO_DOUBLE_BUFFER to control whether the Raspberry Pi and KMSDRM video drivers should use double or triple buffering (the default)
+
+
+---------------------------------------------------------------------------
+2.0.7:
+---------------------------------------------------------------------------
+
+General:
+* Added audio stream conversion functions:
+	SDL_NewAudioStream
+	SDL_AudioStreamPut
+	SDL_AudioStreamGet
+	SDL_AudioStreamAvailable
+	SDL_AudioStreamFlush
+	SDL_AudioStreamClear
+	SDL_FreeAudioStream
+* Added functions to query and set the SDL memory allocation functions:
+	SDL_GetMemoryFunctions()
+	SDL_SetMemoryFunctions()
+	SDL_GetNumAllocations()
+* Added locking functions for multi-threaded access to the joystick and game controller APIs:
+	SDL_LockJoysticks()
+	SDL_UnlockJoysticks()
+* The following functions are now thread-safe:
+	SDL_SetEventFilter()
+	SDL_GetEventFilter()
+	SDL_AddEventWatch()
+	SDL_DelEventWatch()
+
+
+General:
+---------------------------------------------------------------------------
+2.0.6:
+---------------------------------------------------------------------------
+
+General:
+* Added cross-platform Vulkan graphics support in SDL_vulkan.h
+	SDL_Vulkan_LoadLibrary()
+	SDL_Vulkan_GetVkGetInstanceProcAddr()
+	SDL_Vulkan_GetInstanceExtensions()
+	SDL_Vulkan_CreateSurface()
+	SDL_Vulkan_GetDrawableSize()
+	SDL_Vulkan_UnloadLibrary()
+  This is all the platform-specific code you need to bring up Vulkan on all SDL platforms. You can look at an example in test/testvulkan.c
+* Added SDL_ComposeCustomBlendMode() to create custom blend modes for 2D rendering
+* Added SDL_HasNEON() which returns whether the CPU has NEON instruction support
+* Added support for many game controllers, including the Nintendo Switch Pro Controller
+* Added support for inverted axes and separate axis directions in game controller mappings
+* Added functions to return information about a joystick before it's opened:
+	SDL_JoystickGetDeviceVendor()
+	SDL_JoystickGetDeviceProduct()
+	SDL_JoystickGetDeviceProductVersion()
+	SDL_JoystickGetDeviceType()
+	SDL_JoystickGetDeviceInstanceID()
+* Added functions to return information about an open joystick:
+	SDL_JoystickGetVendor()
+	SDL_JoystickGetProduct()
+	SDL_JoystickGetProductVersion()
+	SDL_JoystickGetType()
+	SDL_JoystickGetAxisInitialState()
+* Added functions to return information about an open game controller:
+	SDL_GameControllerGetVendor()
+	SDL_GameControllerGetProduct()
+	SDL_GameControllerGetProductVersion()
+* Added SDL_GameControllerNumMappings() and SDL_GameControllerMappingForIndex() to be able to enumerate the built-in game controller mappings
+* Added SDL_LoadFile() and SDL_LoadFile_RW() to load a file into memory
+* Added SDL_DuplicateSurface() to make a copy of a surface
+* Added an experimental JACK audio driver
+* Implemented non-power-of-two audio resampling, optionally using libsamplerate to perform the resampling
+* Added the hint SDL_HINT_AUDIO_RESAMPLING_MODE to control the quality of resampling
+* Added the hint SDL_HINT_RENDER_LOGICAL_SIZE_MODE to control the scaling policy for SDL_RenderSetLogicalSize():
+	"0" or "letterbox" - Uses letterbox/sidebars to fit the entire rendering on screen (the default)
+	"1" or "overscan"  - Will zoom the rendering so it fills the entire screen, allowing edges to be drawn offscreen
+* Added the hints SDL_HINT_MOUSE_NORMAL_SPEED_SCALE and SDL_HINT_MOUSE_RELATIVE_SPEED_SCALE to scale the mouse speed when being read from raw mouse input
+* Added the hint SDL_HINT_TOUCH_MOUSE_EVENTS to control whether SDL will synthesize mouse events from touch events
+
+Windows:
+* The new default audio driver on Windows is WASAPI and supports hot-plugging devices and changing the default audio device
+* The old XAudio2 audio driver is deprecated and will be removed in the next release
+* Added hints SDL_HINT_WINDOWS_INTRESOURCE_ICON and SDL_HINT_WINDOWS_INTRESOURCE_ICON_SMALL to specify a custom icon resource ID for SDL windows
+* The hint SDL_HINT_WINDOWS_DISABLE_THREAD_NAMING is now on by default for compatibility with .NET languages and various Windows debuggers
+* Updated the GUID format for game controller mappings, older mappings will be automatically converted on load
+* Implemented the SDL_WINDOW_ALWAYS_ON_TOP flag on Windows
+
+Linux:
+* Added an experimental KMS/DRM video driver for embedded development
+
+iOS:
+* Added a hint SDL_HINT_AUDIO_CATEGORY to control the audio category, determining whether the phone mute switch affects the audio
+
+---------------------------------------------------------------------------
+2.0.5:
+---------------------------------------------------------------------------
+
+General:
+* Implemented audio capture support for some platforms
+* Added SDL_DequeueAudio() to retrieve audio when buffer queuing is turned on for audio capture
+* Added events for dragging and dropping text
+* Added events for dragging and dropping multiple items
+* By default the click raising a window will not be delivered to the SDL application. You can set the hint SDL_HINT_MOUSE_FOCUS_CLICKTHROUGH to "1" to allow that click through to the window.
+* Saving a surface with an alpha channel as a BMP will use a newer BMP format that supports alpha information. You can set the hint SDL_HINT_BMP_SAVE_LEGACY_FORMAT to "1" to use the old format.
+* Added SDL_GetHintBoolean() to get the boolean value of a hint
+* Added SDL_RenderSetIntegerScale() to set whether to smoothly scale or use integral multiples of the viewport size when scaling the rendering output
+* Added SDL_CreateRGBSurfaceWithFormat() and SDL_CreateRGBSurfaceWithFormatFrom() to create an SDL surface with a specific pixel format
+* Added SDL_GetDisplayUsableBounds() which returns the area usable for windows. For example, on Mac OS X, this subtracts the area occupied by the menu bar and dock.
+* Added SDL_GetWindowBordersSize() which returns the size of the window's borders around the client area
+* Added a window event SDL_WINDOWEVENT_HIT_TEST when a window had a hit test that wasn't SDL_HITTEST_NORMAL (e.g. in the title bar or window frame)
+* Added SDL_SetWindowResizable() to change whether a window is resizable
+* Added SDL_SetWindowOpacity() and SDL_GetWindowOpacity() to affect the window transparency
+* Added SDL_SetWindowModalFor() to set a window as modal for another window
+* Added support for AUDIO_U16LSB and AUDIO_U16MSB to SDL_MixAudioFormat()
+* Fixed flipped images when reading back from target textures when using the OpenGL renderer
+* Fixed texture color modulation with SDL_BLENDMODE_NONE when using the OpenGL renderer
+* Fixed bug where the alpha value of colorkeys was ignored when blitting in some cases
+
+Windows:
+* Added a hint SDL_HINT_WINDOWS_DISABLE_THREAD_NAMING to prevent SDL from raising a debugger exception to name threads. This exception can cause problems with .NET applications when running under a debugger.
+* The hint SDL_HINT_THREAD_STACK_SIZE is now supported on Windows
+* Fixed XBox controller triggers automatically being pulled at startup
+* The first icon from the executable is used as the default window icon at runtime
+* Fixed SDL log messages being printed twice if SDL was built with C library support
+* Reset dead keys when the SDL window loses focus, so dead keys pressed in SDL applications don't affect text input into other applications.
+
+Mac OS X:
+* Fixed selecting the dummy video driver
+* The caps lock key now generates a pressed event when pressed and a released event when released, instead of a press/release event pair when pressed.
+* Fixed mouse wheel events on Mac OS X 10.12
+* The audio driver has been updated to use AVFoundation for better compatibility with newer versions of Mac OS X
+
+Linux:
+* Added support for the Fcitx IME
+* Added a window event SDL_WINDOWEVENT_TAKE_FOCUS when a window manager asks the SDL window whether it wants to take focus.
+* Refresh rates are now rounded instead of truncated, e.g. 59.94 Hz is rounded up to 60 Hz instead of 59.
+* Added initial support for touchscreens on Raspberry Pi
+
+OpenBSD:
+* SDL_GetBasePath() is now implemented on OpenBSD
+
+iOS:
+* Added support for dynamically loaded objects on iOS 8 and newer
+
+tvOS:
+* Added support for Apple TV
+* Added a hint SDL_HINT_APPLE_TV_REMOTE_ALLOW_ROTATION to control whether he Apple TV remote's joystick axes will automatically match the rotation of the remote.  
+
+Android:
+* Fixed SDL not resizing window when Android screen resolution changes
+* Corrected the joystick Z axis reporting for the accelerometer
+
+Emscripten (running in a web browser):
+* Many bug fixes and improvements
+
+
+---------------------------------------------------------------------------
+2.0.4:
+---------------------------------------------------------------------------
+
+General:
+* Added support for web applications using Emscripten, see docs/README-emscripten.md for more information
+* Added support for web applications using Native Client (NaCl), see docs/README-nacl.md for more information
+* Added an API to queue audio instead of using the audio callback:
+    SDL_QueueAudio(), SDL_GetQueuedAudioSize(), SDL_ClearQueuedAudio()
+* Added events for audio device hot plug support:
+    SDL_AUDIODEVICEADDED, SDL_AUDIODEVICEREMOVED
+* Added SDL_PointInRect()
+* Added SDL_HasAVX2() to detect CPUs with AVX2 support
+* Added SDL_SetWindowHitTest() to let apps treat parts of their SDL window like traditional window decorations (drag areas, resize areas)
+* Added SDL_GetGrabbedWindow() to get the window that currently has input grab, if any
+* Added SDL_RenderIsClipEnabled() to tell whether clipping is currently enabled in a renderer
+* Added SDL_CaptureMouse() to capture the mouse to get events while the mouse is not in your window
+* Added SDL_WarpMouseGlobal() to warp the mouse cursor in global screen space
+* Added SDL_GetGlobalMouseState() to get the current mouse state outside of an SDL window
+* Added a direction field to mouse wheel events to tell whether they are flipped (natural) or not
+* Added GL_CONTEXT_RELEASE_BEHAVIOR GL attribute (maps to [WGL|GLX]_ARB_context_flush_control extension)
+* Added EGL_KHR_create_context support to allow OpenGL ES version selection on some platforms
+* Added NV12 and NV21 YUV texture support for OpenGL and OpenGL ES 2.0 renderers
+* Added a Vivante video driver that is used on various SoC platforms
+* Added an event SDL_RENDER_DEVICE_RESET that is sent from the D3D renderers when the D3D device is lost, and from Android's event loop when the GLES context had to be recreated
+* Added a hint SDL_HINT_NO_SIGNAL_HANDLERS to disable SDL's built in signal handling
+* Added a hint SDL_HINT_THREAD_STACK_SIZE to set the stack size of SDL's threads
+* Added SDL_sqrtf(), SDL_tan(), and SDL_tanf() to the stdlib routines
+* Improved support for WAV and BMP files with unusual chunks in them
+* Renamed SDL_assert_data to SDL_AssertData and SDL_assert_state to SDL_AssertState
+* Added a hint SDL_HINT_WINDOW_FRAME_USABLE_WHILE_CURSOR_HIDDEN to prevent window interaction while cursor is hidden
+* Added SDL_GetDisplayDPI() to get the DPI information for a display
+* Added SDL_JoystickCurrentPowerLevel() to get the battery level of a joystick
+* Added SDL_JoystickFromInstanceID(), as a helper function, to get the SDL_Joystick* that an event is referring to.
+* Added SDL_GameControllerFromInstanceID(), as a helper function, to get the SDL_GameController* that an event is referring to.
+
+Windows:
+* Added support for Windows Phone 8.1 and Windows 10/UWP (Universal Windows Platform)
+* Timer resolution is now 1 ms by default, adjustable with the SDL_HINT_TIMER_RESOLUTION hint
+* SDLmain no longer depends on the C runtime, so you can use the same .lib in both Debug and Release builds
+* Added SDL_SetWindowsMessageHook() to set a function to be called for every windows message before TranslateMessage()
+* Added a hint SDL_HINT_WINDOWS_ENABLE_MESSAGELOOP to control whether SDL_PumpEvents() processes the Windows message loop
+* You can distinguish between real mouse and touch events by looking for SDL_TOUCH_MOUSEID in the mouse event "which" field
+* SDL_SysWMinfo now contains the window HDC
+* Added support for Unicode command line options
+* Prevent beeping when Alt-key combos are pressed
+* SDL_SetTextInputRect() re-positions the OS-rendered IME
+* Added a hint SDL_HINT_WINDOWS_NO_CLOSE_ON_ALT_F4 to prevent generating SDL_WINDOWEVENT_CLOSE events when Alt-F4 is pressed
+* Added a hint SDL_HINT_XINPUT_USE_OLD_JOYSTICK_MAPPING to use the old axis and button mapping for XInput devices (deprecated)
+
+Mac OS X:
+* Implemented drag-and-drop support
+* Improved joystick hot-plug detection
+* The SDL_WINDOWEVENT_EXPOSED window event is triggered in the appropriate situations
+* Fixed relative mouse mode when the application loses/regains focus
+* Fixed bugs related to transitioning to and from Spaces-aware fullscreen-desktop mode
+* Fixed the refresh rate of display modes
+* SDL_SysWMInfo is now ARC-compatible
+* Added a hint SDL_HINT_MAC_BACKGROUND_APP to prevent forcing the application to become a foreground process
+
+Linux:
+* Enabled building with Mir and Wayland support by default.
+* Added IBus IME support
+* Added a hint SDL_HINT_IME_INTERNAL_EDITING to control whether IBus should handle text editing internally instead of sending SDL_TEXTEDITING events
+* Added a hint SDL_HINT_VIDEO_X11_NET_WM_PING to allow disabling _NET_WM_PING protocol handling in SDL_CreateWindow()
+* Added support for multiple audio devices when using Pulseaudio
+* Fixed duplicate mouse events when using relative mouse motion
+
+iOS:
+* Added support for iOS 8
+* The SDL_WINDOW_ALLOW_HIGHDPI window flag now enables high-dpi support, and SDL_GL_GetDrawableSize() or SDL_GetRendererOutputSize() gets the window resolution in pixels
+* SDL_GetWindowSize() and display mode sizes are in the "DPI-independent points" / "screen coordinates" coordinate space rather than pixels (matches OS X behavior)
+* Added native resolution support for the iPhone 6 Plus
+* Added support for MFi game controllers
+* Added support for the hint SDL_HINT_ACCELEROMETER_AS_JOYSTICK
+* Added sRGB OpenGL ES context support on iOS 7+
+* Added support for SDL_DisableScreenSaver(), SDL_EnableScreenSaver() and the hint SDL_HINT_VIDEO_ALLOW_SCREENSAVER
+* SDL_SysWMinfo now contains the OpenGL ES framebuffer and color renderbuffer objects used by the window's active GLES view
+* Fixed various rotation and orientation issues
+* Fixed memory leaks
+
+Android:
+* Added a hint SDL_HINT_ANDROID_SEPARATE_MOUSE_AND_TOUCH to prevent mouse events from being registered as touch events
+* Added hints SDL_HINT_ANDROID_APK_EXPANSION_MAIN_FILE_VERSION and SDL_HINT_ANDROID_APK_EXPANSION_PATCH_FILE_VERSION
+* Added support for SDL_DisableScreenSaver(), SDL_EnableScreenSaver() and the hint SDL_HINT_VIDEO_ALLOW_SCREENSAVER
+* Added support for SDL_ShowMessageBox() and SDL_ShowSimpleMessageBox()
+
+Raspberry Pi:
+* Added support for the Raspberry Pi 2
+
+
+---------------------------------------------------------------------------
+2.0.3:
+---------------------------------------------------------------------------
+
+Mac OS X:
+* Fixed creating an OpenGL context by default on Mac OS X 10.6
+
+
+---------------------------------------------------------------------------
+2.0.2:
+---------------------------------------------------------------------------
+General:
+* Added SDL_GL_ResetAttributes() to reset OpenGL attributes to default values
+* Added an API to load a database of game controller mappings from a file:
+    SDL_GameControllerAddMappingsFromFile(), SDL_GameControllerAddMappingsFromRW()
+* Added game controller mappings for the PS4 and OUYA controllers
+* Added SDL_GetDefaultAssertionHandler() and SDL_GetAssertionHandler()
+* Added SDL_DetachThread()
+* Added SDL_HasAVX() to determine if the CPU has AVX features
+* Added SDL_vsscanf(), SDL_acos(), and SDL_asin() to the stdlib routines
+* EGL can now create/manage OpenGL and OpenGL ES 1.x/2.x contexts, and share
+  them using SDL_GL_SHARE_WITH_CURRENT_CONTEXT
+* Added a field "clicks" to the mouse button event which records whether the event is a single click, double click, etc.
+* The screensaver is now disabled by default, and there is a hint SDL_HINT_VIDEO_ALLOW_SCREENSAVER that can change that behavior.
+* Added a hint SDL_HINT_MOUSE_RELATIVE_MODE_WARP to specify whether mouse relative mode should be emulated using mouse warping.
+* testgl2 does not need to link with libGL anymore
+* Added testgles2 test program to demonstrate working with OpenGL ES 2.0
+* Added controllermap test program to visually map a game controller
+
+Windows:
+* Support for OpenGL ES 2.x contexts using either WGL or EGL (natively via
+  the driver or emulated through ANGLE)
+* Added a hint SDL_HINT_VIDEO_WIN_D3DCOMPILER to specify which D3D shader compiler to use for OpenGL ES 2 support through ANGLE
+* Added a hint SDL_HINT_VIDEO_WINDOW_SHARE_PIXEL_FORMAT that is useful when creating multiple windows that should share the same OpenGL context.
+* Added an event SDL_RENDER_TARGETS_RESET that is sent when D3D9 render targets are reset after the device has been restored.
+
+Mac OS X:
+* Added a hint SDL_HINT_MAC_CTRL_CLICK_EMULATE_RIGHT_CLICK to control whether Ctrl+click should be treated as a right click on Mac OS X. This is off by default.
+
+Linux:
+* Fixed fullscreen and focused behavior when receiving NotifyGrab events
+* Added experimental Wayland and Mir support, disabled by default
+
+Android:
+* Joystick support (minimum SDK version required to build SDL is now 12, 
+  the required runtime version remains at 10, but on such devices joystick 
+  support won't be available).
+* Hotplugging support for joysticks
+* Added a hint SDL_HINT_ACCELEROMETER_AS_JOYSTICK to control whether the accelerometer should be listed as a 3 axis joystick, which it will by default.
+
+
+---------------------------------------------------------------------------
+2.0.1:
+---------------------------------------------------------------------------
+
+General:
+* Added an API to get common filesystem paths in SDL_filesystem.h:
+    SDL_GetBasePath(), SDL_GetPrefPath()
+* Added an API to do optimized YV12 and IYUV texture updates:
+    SDL_UpdateYUVTexture()
+* Added an API to get the amount of RAM on the system:
+    SDL_GetSystemRAM()
+* Added a macro to perform timestamp comparisons with SDL_GetTicks():
+    SDL_TICKS_PASSED()
+* Dramatically improved OpenGL ES 2.0 rendering performance
+* Added OpenGL attribute SDL_GL_FRAMEBUFFER_SRGB_CAPABLE
+
+Windows:
+* Created a static library configuration for the Visual Studio 2010 project
+* Added a hint to create the Direct3D device with support for multi-threading:
+    SDL_HINT_RENDER_DIRECT3D_THREADSAFE
+* Added a function to get the D3D9 adapter index for a display:
+    SDL_Direct3D9GetAdapterIndex()
+* Added a function to get the D3D9 device for a D3D9 renderer:
+    SDL_RenderGetD3D9Device()
+* Fixed building SDL with the mingw32 toolchain (mingw-w64 is preferred)
+* Fixed crash when using two XInput controllers at the same time
+* Fixed detecting a mixture of XInput and DirectInput controllers
+* Fixed clearing a D3D render target larger than the window
+* Improved support for format specifiers in SDL_snprintf()
+
+Mac OS X:
+* Added support for retina displays:
+  Create your window with the SDL_WINDOW_ALLOW_HIGHDPI flag, and then use SDL_GL_GetDrawableSize() to find the actual drawable size. You are responsible for scaling mouse and drawing coordinates appropriately.
+* Fixed mouse warping in fullscreen mode
+* Right mouse click is emulated by holding the Ctrl key while left clicking
+
+Linux:
+* Fixed float audio support with the PulseAudio driver
+* Fixed missing line endpoints in the OpenGL renderer on some drivers
+* X11 symbols are no longer defined to avoid collisions when linking statically
+
+iOS:
+* Fixed status bar visibility on iOS 7
+* Flipped the accelerometer Y axis to match expected values
+
+Android:
+IMPORTANT: You MUST get the updated SDLActivity.java to match C code
+* Moved EGL initialization to native code 
+* Fixed the accelerometer axis rotation relative to the device rotation
+* Fixed race conditions when handling the EGL context on pause/resume
+* Touch devices are available for enumeration immediately after init
+
+Raspberry Pi:
+* Added support for the Raspberry Pi, see README-raspberrypi.txt for details

libs/SDL2/docs/README-android.md

+Android
+================================================================================
+
+Matt Styles wrote a tutorial on building SDL for Android with Visual Studio:
+http://trederia.blogspot.de/2017/03/building-sdl2-for-android-with-visual.html
+
+The rest of this README covers the Android gradle style build process.
+
+If you are using the older ant build process, it is no longer officially
+supported, but you can use the "android-project-ant" directory as a template.
+
+
+================================================================================
+ Requirements
+================================================================================
+
+Android SDK (version 26 or later)
+https://developer.android.com/sdk/index.html
+
+Android NDK r15c or later
+https://developer.android.com/tools/sdk/ndk/index.html
+
+Minimum API level supported by SDL: 16 (Android 4.1)
+
+
+================================================================================
+ How the port works
+================================================================================
+
+- Android applications are Java-based, optionally with parts written in C
+- As SDL apps are C-based, we use a small Java shim that uses JNI to talk to 
+  the SDL library
+- This means that your application C code must be placed inside an Android 
+  Java project, along with some C support code that communicates with Java
+- This eventually produces a standard Android .apk package
+
+The Android Java code implements an "Activity" and can be found in:
+android-project/app/src/main/java/org/libsdl/app/SDLActivity.java
+
+The Java code loads your game code, the SDL shared library, and
+dispatches to native functions implemented in the SDL library:
+src/core/android/SDL_android.c
+
+
+================================================================================
+ Building an app
+================================================================================
+
+For simple projects you can use the script located at build-scripts/androidbuild.sh
+
+There's two ways of using it:
+
+    androidbuild.sh com.yourcompany.yourapp < sources.list
+    androidbuild.sh com.yourcompany.yourapp source1.c source2.c ...sourceN.c
+
+sources.list should be a text file with a source file name in each line
+Filenames should be specified relative to the current directory, for example if
+you are in the build-scripts directory and want to create the testgles.c test, you'll
+run:
+
+    ./androidbuild.sh org.libsdl.testgles ../test/testgles.c
+
+One limitation of this script is that all sources provided will be aggregated into
+a single directory, thus all your source files should have a unique name.
+
+Once the project is complete the script will tell you where the debug APK is located.
+If you want to create a signed release APK, you can use the project created by this
+utility to generate it.
+
+Finally, a word of caution: re running androidbuild.sh wipes any changes you may have
+done in the build directory for the app!
+
+
+For more complex projects, follow these instructions:
+    
+1. Copy the android-project directory wherever you want to keep your projects
+   and rename it to the name of your project.
+2. Move or symlink this SDL directory into the "<project>/app/jni" directory
+3. Edit "<project>/app/jni/src/Android.mk" to include your source files
+
+4a. If you want to use Android Studio, simply open your <project> directory and start building.
+
+4b. If you want to build manually, run './gradlew installDebug' in the project directory. This compiles the .java, creates an .apk with the native code embedded, and installs it on any connected Android device
+
+Here's an explanation of the files in the Android project, so you can customize them:
+
+    android-project/app
+        build.gradle            - build info including the application version and SDK
+        src/main/AndroidManifest.xml	- package manifest. Among others, it contains the class name of the main Activity and the package name of the application.
+        jni/			- directory holding native code
+        jni/Application.mk	- Application JNI settings, including target platform and STL library
+        jni/Android.mk		- Android makefile that can call recursively the Android.mk files in all subdirectories
+        jni/SDL/		- (symlink to) directory holding the SDL library files
+        jni/SDL/Android.mk	- Android makefile for creating the SDL shared library
+        jni/src/		- directory holding your C/C++ source
+        jni/src/Android.mk	- Android makefile that you should customize to include your source code and any library references
+        src/main/assets/	- directory holding asset files for your application
+        src/main/res/		- directory holding resources for your application
+        src/main/res/mipmap-*	- directories holding icons for different phone hardware
+        src/main/res/values/strings.xml	- strings used in your application, including the application name
+        src/main/java/org/libsdl/app/SDLActivity.java - the Java class handling the initialization and binding to SDL. Be very careful changing this, as the SDL library relies on this implementation. You should instead subclass this for your application.
+
+
+================================================================================
+ Customizing your application name
+================================================================================
+
+To customize your application name, edit AndroidManifest.xml and replace
+"org.libsdl.app" with an identifier for your product package.
+
+Then create a Java class extending SDLActivity and place it in a directory
+under src matching your package, e.g.
+
+    src/com/gamemaker/game/MyGame.java
+
+Here's an example of a minimal class file:
+
+    --- MyGame.java --------------------------
+    package com.gamemaker.game;
+    
+    import org.libsdl.app.SDLActivity; 
+    
+    /**
+     * A sample wrapper class that just calls SDLActivity 
+     */ 
+    
+    public class MyGame extends SDLActivity { }
+    
+    ------------------------------------------
+
+Then replace "SDLActivity" in AndroidManifest.xml with the name of your
+class, .e.g. "MyGame"
+
+
+================================================================================
+ Customizing your application icon
+================================================================================
+
+Conceptually changing your icon is just replacing the "ic_launcher.png" files in
+the drawable directories under the res directory. There are several directories
+for different screen sizes.
+
+
+================================================================================
+ Loading assets
+================================================================================
+
+Any files you put in the "app/src/main/assets" directory of your project
+directory will get bundled into the application package and you can load
+them using the standard functions in SDL_rwops.h.
+
+There are also a few Android specific functions that allow you to get other
+useful paths for saving and loading data:
+* SDL_AndroidGetInternalStoragePath()
+* SDL_AndroidGetExternalStorageState()
+* SDL_AndroidGetExternalStoragePath()
+
+See SDL_system.h for more details on these functions.
+
+The asset packaging system will, by default, compress certain file extensions.
+SDL includes two asset file access mechanisms, the preferred one is the so
+called "File Descriptor" method, which is faster and doesn't involve the Dalvik
+GC, but given this method does not work on compressed assets, there is also the
+"Input Stream" method, which is automatically used as a fall back by SDL. You
+may want to keep this fact in mind when building your APK, specially when large
+files are involved.
+For more information on which extensions get compressed by default and how to
+disable this behaviour, see for example:
+    
+http://ponystyle.com/blog/2010/03/26/dealing-with-asset-compression-in-android-apps/
+
+
+================================================================================
+ Pause / Resume behaviour
+================================================================================
+
+If SDL_HINT_ANDROID_BLOCK_ON_PAUSE hint is set (the default),
+the event loop will block itself when the app is paused (ie, when the user
+returns to the main Android dashboard). Blocking is better in terms of battery
+use, and it allows your app to spring back to life instantaneously after resume
+(versus polling for a resume message).
+
+Upon resume, SDL will attempt to restore the GL context automatically.
+In modern devices (Android 3.0 and up) this will most likely succeed and your
+app can continue to operate as it was.
+
+However, there's a chance (on older hardware, or on systems under heavy load),
+where the GL context can not be restored. In that case you have to listen for
+a specific message, (which is not yet implemented!) and restore your textures
+manually or quit the app (which is actually the kind of behaviour you'll see
+under iOS, if the OS can not restore your GL context it will just kill your app)
+
+
+================================================================================
+ Threads and the Java VM
+================================================================================
+
+For a quick tour on how Linux native threads interoperate with the Java VM, take
+a look here: https://developer.android.com/guide/practices/jni.html
+
+If you want to use threads in your SDL app, it's strongly recommended that you
+do so by creating them using SDL functions. This way, the required attach/detach
+handling is managed by SDL automagically. If you have threads created by other
+means and they make calls to SDL functions, make sure that you call
+Android_JNI_SetupThread() before doing anything else otherwise SDL will attach
+your thread automatically anyway (when you make an SDL call), but it'll never
+detach it.
+
+
+================================================================================
+ Using STL
+================================================================================
+
+You can use STL in your project by creating an Application.mk file in the jni
+folder and adding the following line:
+
+    APP_STL := c++_shared
+
+For more information go here:
+	https://developer.android.com/ndk/guides/cpp-support
+
+
+================================================================================
+ Using the emulator
+================================================================================
+
+There are some good tips and tricks for getting the most out of the
+emulator here: https://developer.android.com/tools/devices/emulator.html
+
+Especially useful is the info on setting up OpenGL ES 2.0 emulation.
+
+Notice that this software emulator is incredibly slow and needs a lot of disk space.
+Using a real device works better.
+
+
+================================================================================
+ Troubleshooting
+================================================================================
+
+You can see if adb can see any devices with the following command:
+
+    adb devices
+
+You can see the output of log messages on the default device with:
+
+    adb logcat
+
+You can push files to the device with:
+
+    adb push local_file remote_path_and_file
+
+You can push files to the SD Card at /sdcard, for example:
+
+    adb push moose.dat /sdcard/moose.dat
+
+You can see the files on the SD card with a shell command:
+
+    adb shell ls /sdcard/
+
+You can start a command shell on the default device with:
+
+    adb shell
+
+You can remove the library files of your project (and not the SDL lib files) with:
+
+    ndk-build clean
+
+You can do a build with the following command:
+
+    ndk-build
+
+You can see the complete command line that ndk-build is using by passing V=1 on the command line:
+
+    ndk-build V=1
+
+If your application crashes in native code, you can use ndk-stack to get a symbolic stack trace:
+	https://developer.android.com/ndk/guides/ndk-stack
+
+If you want to go through the process manually, you can use addr2line to convert the
+addresses in the stack trace to lines in your code.
+
+For example, if your crash looks like this:
+
+    I/DEBUG   (   31): signal 11 (SIGSEGV), code 2 (SEGV_ACCERR), fault addr 400085d0
+    I/DEBUG   (   31):  r0 00000000  r1 00001000  r2 00000003  r3 400085d4
+    I/DEBUG   (   31):  r4 400085d0  r5 40008000  r6 afd41504  r7 436c6a7c
+    I/DEBUG   (   31):  r8 436c6b30  r9 435c6fb0  10 435c6f9c  fp 4168d82c
+    I/DEBUG   (   31):  ip 8346aff0  sp 436c6a60  lr afd1c8ff  pc afd1c902  cpsr 60000030
+    I/DEBUG   (   31):          #00  pc 0001c902  /system/lib/libc.so
+    I/DEBUG   (   31):          #01  pc 0001ccf6  /system/lib/libc.so
+    I/DEBUG   (   31):          #02  pc 000014bc  /data/data/org.libsdl.app/lib/libmain.so
+    I/DEBUG   (   31):          #03  pc 00001506  /data/data/org.libsdl.app/lib/libmain.so
+
+You can see that there's a crash in the C library being called from the main code.
+I run addr2line with the debug version of my code:
+
+    arm-eabi-addr2line -C -f -e obj/local/armeabi/libmain.so
+
+and then paste in the number after "pc" in the call stack, from the line that I care about:
+000014bc
+
+I get output from addr2line showing that it's in the quit function, in testspriteminimal.c, on line 23.
+
+You can add logging to your code to help show what's happening:
+
+    #include <android/log.h>
+    
+    __android_log_print(ANDROID_LOG_INFO, "foo", "Something happened! x = %d", x);
+
+If you need to build without optimization turned on, you can create a file called
+"Application.mk" in the jni directory, with the following line in it:
+
+    APP_OPTIM := debug
+
+
+================================================================================
+ Memory debugging
+================================================================================
+
+The best (and slowest) way to debug memory issues on Android is valgrind.
+Valgrind has support for Android out of the box, just grab code using:
+
+    svn co svn://svn.valgrind.org/valgrind/trunk valgrind
+
+... and follow the instructions in the file README.android to build it.
+
+One thing I needed to do on Mac OS X was change the path to the toolchain,
+and add ranlib to the environment variables:
+export RANLIB=$NDKROOT/toolchains/arm-linux-androideabi-4.4.3/prebuilt/darwin-x86/bin/arm-linux-androideabi-ranlib
+
+Once valgrind is built, you can create a wrapper script to launch your
+application with it, changing org.libsdl.app to your package identifier:
+
+    --- start_valgrind_app -------------------
+    #!/system/bin/sh
+    export TMPDIR=/data/data/org.libsdl.app
+    exec /data/local/Inst/bin/valgrind --log-file=/sdcard/valgrind.log --error-limit=no $*
+    ------------------------------------------
+
+Then push it to the device:
+
+    adb push start_valgrind_app /data/local
+
+and make it executable:
+
+    adb shell chmod 755 /data/local/start_valgrind_app
+
+and tell Android to use the script to launch your application:
+
+    adb shell setprop wrap.org.libsdl.app "logwrapper /data/local/start_valgrind_app"
+
+If the setprop command says "could not set property", it's likely that
+your package name is too long and you should make it shorter by changing
+AndroidManifest.xml and the path to your class file in android-project/src
+
+You can then launch your application normally and waaaaaaaiiittt for it.
+You can monitor the startup process with the logcat command above, and
+when it's done (or even while it's running) you can grab the valgrind
+output file:
+
+    adb pull /sdcard/valgrind.log
+
+When you're done instrumenting with valgrind, you can disable the wrapper:
+
+    adb shell setprop wrap.org.libsdl.app ""
+
+
+================================================================================
+ Graphics debugging
+================================================================================
+
+If you are developing on a compatible Tegra-based tablet, NVidia provides
+Tegra Graphics Debugger at their website. Because SDL2 dynamically loads EGL
+and GLES libraries, you must follow their instructions for installing the
+interposer library on a rooted device. The non-rooted instructions are not
+compatible with applications that use SDL2 for video.
+
+The Tegra Graphics Debugger is available from NVidia here:
+https://developer.nvidia.com/tegra-graphics-debugger
+
+
+================================================================================
+ Why is API level 16 the minimum required?
+================================================================================
+
+The latest NDK toolchain doesn't support targeting earlier than API level 16.
+As of this writing, according to https://developer.android.com/about/dashboards/index.html
+about 99% of the Android devices accessing Google Play support API level 16 or
+higher (January 2018).
+
+
+================================================================================
+ A note regarding the use of the "dirty rectangles" rendering technique
+================================================================================
+
+If your app uses a variation of the "dirty rectangles" rendering technique,
+where you only update a portion of the screen on each frame, you may notice a
+variety of visual glitches on Android, that are not present on other platforms.
+This is caused by SDL's use of EGL as the support system to handle OpenGL ES/ES2
+contexts, in particular the use of the eglSwapBuffers function. As stated in the
+documentation for the function "The contents of ancillary buffers are always 
+undefined after calling eglSwapBuffers".
+Setting the EGL_SWAP_BEHAVIOR attribute of the surface to EGL_BUFFER_PRESERVED
+is not possible for SDL as it requires EGL 1.4, available only on the API level
+17+, so the only workaround available on this platform is to redraw the entire
+screen each frame.
+
+Reference: http://www.khronos.org/registry/egl/specs/EGLTechNote0001.html
+
+
+================================================================================
+ Ending your application
+================================================================================
+
+Two legitimate ways:
+
+- return from your main() function. Java side will automatically terminate the
+Activity by calling Activity.finish().
+
+- Android OS can decide to terminate your application by calling onDestroy()
+(see Activity life cycle). Your application will receive a SDL_QUIT event you 
+can handle to save things and quit.
+
+Don't call exit() as it stops the activity badly.
+
+NB: "Back button" can be handled as a SDL_KEYDOWN/UP events, with Keycode
+SDLK_AC_BACK, for any purpose.
+
+================================================================================
+ Known issues
+================================================================================
+
+- The number of buttons reported for each joystick is hardcoded to be 36, which
+is the current maximum number of buttons Android can report.
+

libs/SDL2/docs/README-cmake.md

+CMake
+================================================================================
+(www.cmake.org)
+
+SDL's build system was traditionally based on autotools. Over time, this
+approach has suffered from several issues across the different supported 
+platforms.
+To solve these problems, a new build system based on CMake is under development.
+It works in parallel to the legacy system, so users can experiment with it
+without complication.
+While still experimental, the build system should be usable on the following
+platforms:
+
+* FreeBSD
+* Linux
+* VS.NET 2010
+* MinGW and Msys
+* OS X with support for XCode
+
+
+================================================================================
+Usage
+================================================================================
+
+Assuming the source for SDL is located at ~/sdl
+
+    cd ~
+    mkdir build
+    cd build
+    cmake ../sdl
+
+This will build the static and dynamic versions of SDL in the ~/build directory.

libs/SDL2/docs/README-directfb.md

+DirectFB
+========
+
+Supports:
+
+- Hardware YUV overlays
+- OpenGL - software only
+- 2D/3D accelerations (depends on directfb driver)
+- multiple displays
+- windows
+
+What you need:
+
+* DirectFB 1.0.1, 1.2.x, 1.3.0
+* Kernel-Framebuffer support: required: vesafb, radeonfb .... 
+* Mesa 7.0.x	   - optional for OpenGL
+
+/etc/directfbrc
+
+This file should contain the following lines to make
+your joystick work and avoid crashes:
+------------------------
+disable-module=joystick
+disable-module=cle266
+disable-module=cyber5k
+no-linux-input-grab
+------------------------
+
+To disable to use x11 backend when DISPLAY variable is found use
+
+export SDL_DIRECTFB_X11_CHECK=0
+
+To disable the use of linux input devices, i.e. multimice/multikeyboard support,
+use
+
+export SDL_DIRECTFB_LINUX_INPUT=0
+
+To use hardware accelerated YUV-overlays for YUV-textures, use:
+
+export SDL_DIRECTFB_YUV_DIRECT=1
+
+This is disabled by default. It will only support one 
+YUV texture, namely the first. Every other YUV texture will be
+rendered in software.
+
+In addition, you may use (directfb-1.2.x)
+
+export SDL_DIRECTFB_YUV_UNDERLAY=1
+
+to make the YUV texture an underlay. This will make the cursor to
+be shown.
+
+Simple Window Manager
+=====================
+
+The driver has support for a very, very basic window manager you may
+want to use when running with "wm=default". Use
+
+export SDL_DIRECTFB_WM=1
+
+to enable basic window borders. In order to have the window title rendered,
+you need to have the following font installed:
+
+/usr/share/fonts/truetype/freefont/FreeSans.ttf
+
+OpenGL Support
+==============
+
+The following instructions will give you *software* OpenGL. However this
+works at least on all directfb supported platforms.
+
+As of this writing 20100802 you need to pull Mesa from git and do the following:
+
+------------------------
+git clone git://anongit.freedesktop.org/git/mesa/mesa
+cd mesa 
+git checkout 2c9fdaf7292423c157fc79b5ce43f0f199dd753a
+------------------------
+
+Edit configs/linux-directfb so that the Directories-section looks like
+------------------------
+# Directories
+SRC_DIRS     = mesa glu 
+GLU_DIRS     = sgi
+DRIVER_DIRS  = directfb
+PROGRAM_DIRS = 
+------------------------
+
+make linux-directfb
+make
+
+echo Installing - please enter sudo pw.
+
+sudo make install INSTALL_DIR=/usr/local/dfb_GL
+cd src/mesa/drivers/directfb
+make
+sudo make install INSTALL_DIR=/usr/local/dfb_GL
+------------------------
+
+To run the SDL - testprograms:
+
+export SDL_VIDEODRIVER=directfb
+export LD_LIBRARY_PATH=/usr/local/dfb_GL/lib
+export LD_PRELOAD=/usr/local/dfb_GL/libGL.so.7
+
+./testgl
+

libs/SDL2/docs/README-dynapi.md

+Dynamic API
+================================================================================
+Originally posted by Ryan at:
+  https://plus.google.com/103391075724026391227/posts/TB8UfnDYu4U
+
+Background:
+
+- The Steam Runtime has (at least in theory) a really kick-ass build of SDL2, 
+  but developers are shipping their own SDL2 with individual Steam games. 
+  These games might stop getting updates, but a newer SDL2 might be needed later. 
+  Certainly we'll always be fixing bugs in SDL, even if a new video target isn't 
+  ever needed, and these fixes won't make it to a game shipping its own SDL.
+- Even if we replace the SDL2 in those games with a compatible one, that is to 
+  say, edit a developer's Steam depot (yuck!), there are developers that are 
+  statically linking SDL2 that we can't do this for. We can't even force the 
+  dynamic loader to ignore their SDL2 in this case, of course.
+- If you don't ship an SDL2 with the game in some form, people that disabled the
+  Steam Runtime, or just tried to run the game from the command line instead of 
+  Steam might find themselves unable to run the game, due to a missing dependency.
+- If you want to ship on non-Steam platforms like GOG or Humble Bundle, or target
+  generic Linux boxes that may or may not have SDL2 installed, you have to ship 
+  the library or risk a total failure to launch. So now, you might have to have 
+  a non-Steam build plus a Steam build (that is, one with and one without SDL2 
+  included), which is inconvenient if you could have had one universal build 
+  that works everywhere.
+- We like the zlib license, but the biggest complaint from the open source 
+  community about the license change is the static linking. The LGPL forced this 
+  as a legal, not technical issue, but zlib doesn't care. Even those that aren't
+  concerned about the GNU freedoms found themselves solving the same problems: 
+  swapping in a newer SDL to an older game often times can save the day. 
+  Static linking stops this dead.
+
+So here's what we did:
+
+SDL now has, internally, a table of function pointers. So, this is what SDL_Init
+now looks like:
+
+    UInt32 SDL_Init(Uint32 flags)
+    {
+        return jump_table.SDL_Init(flags);
+    }
+
+Except that is all done with a bunch of macro magic so we don't have to maintain
+every one of these.
+
+What is jump_table.SDL_init()? Eventually, that's a function pointer of the real
+SDL_Init() that you've been calling all this time. But at startup, it looks more 
+like this:
+
+    Uint32 SDL_Init_DEFAULT(Uint32 flags)
+    {
+        SDL_InitDynamicAPI();
+        return jump_table.SDL_Init(flags);
+    }
+
+SDL_InitDynamicAPI() fills in jump_table with all the actual SDL function 
+pointers, which means that this _DEFAULT function never gets called again. 
+First call to any SDL function sets the whole thing up.
+
+So you might be asking, what was the value in that? Isn't this what the operating
+system's dynamic loader was supposed to do for us? Yes, but now we've got this 
+level of indirection, we can do things like this:
+
+    export SDL_DYNAMIC_API=/my/actual/libSDL-2.0.so.0
+    ./MyGameThatIsStaticallyLinkedToSDL2
+
+And now, this game that is statically linked to SDL, can still be overridden 
+with a newer, or better, SDL. The statically linked one will only be used as 
+far as calling into the jump table in this case. But in cases where no override
+is desired, the statically linked version will provide its own jump table, 
+and everyone is happy.
+
+So now:
+- Developers can statically link SDL, and users can still replace it. 
+  (We'd still rather you ship a shared library, though!)
+- Developers can ship an SDL with their game, Valve can override it for, say, 
+  new features on SteamOS, or distros can override it for their own needs, 
+  but it'll also just work in the default case.
+- Developers can ship the same package to everyone (Humble Bundle, GOG, etc), 
+  and it'll do the right thing.
+- End users (and Valve) can update a game's SDL in almost any case, 
+  to keep abandoned games running on newer platforms.
+- Everyone develops with SDL exactly as they have been doing all along. 
+  Same headers, same ABI. Just get the latest version to enable this magic.
+
+
+A little more about SDL_InitDynamicAPI():
+
+Internally, InitAPI does some locking to make sure everything waits until a 
+single thread initializes everything (although even SDL_CreateThread() goes 
+through here before spinning a thread, too), and then decides if it should use
+an external SDL library. If not, it sets up the jump table using the current 
+SDL's function pointers (which might be statically linked into a program, or in
+a shared library of its own). If so, it loads that library and looks for and 
+calls a single function:
+
+    SInt32 SDL_DYNAPI_entry(Uint32 version, void *table, Uint32 tablesize);
+
+That function takes a version number (more on that in a moment), the address of
+the jump table, and the size, in bytes, of the table. 
+Now, we've got policy here: this table's layout never changes; new stuff gets 
+added to the end. Therefore SDL_DYNAPI_entry() knows that it can provide all 
+the needed functions if tablesize <= sizeof its own jump table. If tablesize is
+bigger (say, SDL 2.0.4 is trying to load SDL 2.0.3), then we know to abort, but
+if it's smaller, we know we can provide the entire API that the caller needs.
+
+The version variable is a failsafe switch. 
+Right now it's always 1. This number changes when there are major API changes 
+(so we know if the tablesize might be smaller, or entries in it have changed). 
+Right now SDL_DYNAPI_entry gives up if the version doesn't match, but it's not 
+inconceivable to have a small dispatch library that only supplies this one 
+function and loads different, otherwise-incompatible SDL libraries and has the
+right one initialize the jump table based on the version. For something that 
+must generically catch lots of different versions of SDL over time, like the 
+Steam Client, this isn't a bad option.
+
+Finally, I'm sure some people are reading this and thinking,
+"I don't want that overhead in my project!"  
+To which I would point out that the extra function call through the jump table 
+probably wouldn't even show up in a profile, but lucky you: this can all be 
+disabled. You can build SDL without this if you absolutely must, but we would 
+encourage you not to do that. However, on heavily locked down platforms like 
+iOS, or maybe when debugging, it makes sense to disable it. The way this is
+designed in SDL, you just have to change one #define, and the entire system 
+vaporizes out, and SDL functions exactly like it always did. Most of it is 
+macro magic, so the system is contained to one C file and a few headers. 
+However, this is on by default and you have to edit a header file to turn it 
+off. Our hopes is that if we make it easy to disable, but not too easy, 
+everyone will ultimately be able to get what they want, but we've gently 
+nudged everyone towards what we think is the best solution.

libs/SDL2/docs/README-emscripten.md

+Emscripten
+================================================================================
+
+Build:
+
+    $ mkdir build
+    $ cd build
+    $ emconfigure ../configure --host=asmjs-unknown-emscripten --disable-assembly --disable-threads --disable-cpuinfo CFLAGS="-O2"
+    $ emmake make
+
+Or with cmake:
+
+    $ mkdir build
+    $ cd build
+    $ emcmake cmake ..
+    $ emmake make
+
+To build one of the tests:
+
+    $ cd test/
+    $ emcc -O2 --js-opts 0 -g4 testdraw2.c -I../include ../build/.libs/libSDL2.a ../build/libSDL2_test.a -o a.html
+
+Uses GLES2 renderer or software
+
+Some other SDL2 libraries can be easily built (assuming SDL2 is installed somewhere):
+
+SDL_mixer (http://www.libsdl.org/projects/SDL_mixer/):
+
+    $ EMCONFIGURE_JS=1 emconfigure ../configure
+    build as usual...
+
+SDL_gfx (http://cms.ferzkopp.net/index.php/software/13-sdl-gfx):
+
+    $ EMCONFIGURE_JS=1 emconfigure ../configure --disable-mmx
+    build as usual...

libs/SDL2/docs/README-gesture.md

+Dollar Gestures
+===========================================================================
+SDL provides an implementation of the $1 gesture recognition system. This allows for recording, saving, loading, and performing single stroke gestures.
+
+Gestures can be performed with any number of fingers (the centroid of the fingers must follow the path of the gesture), but the number of fingers must be constant (a finger cannot go down in the middle of a gesture). The path of a gesture is considered the path from the time when the final finger went down, to the first time any finger comes up. 
+
+Dollar gestures are assigned an Id based on a hash function. This is guaranteed to remain constant for a given gesture. There is a (small) chance that two different gestures will be assigned the same ID. In this case, simply re-recording one of the gestures should result in a different ID.
+
+Recording:
+----------
+To begin recording on a touch device call:
+SDL_RecordGesture(SDL_TouchID touchId), where touchId is the id of the touch device you wish to record on, or -1 to record on all connected devices.
+
+Recording terminates as soon as a finger comes up. Recording is acknowledged by an SDL_DOLLARRECORD event.
+A SDL_DOLLARRECORD event is a dgesture with the following fields:
+
+* event.dgesture.touchId   - the Id of the touch used to record the gesture.
+* event.dgesture.gestureId - the unique id of the recorded gesture.
+
+
+Performing:
+-----------
+As long as there is a dollar gesture assigned to a touch, every finger-up event will also cause an SDL_DOLLARGESTURE event with the following fields:
+
+* event.dgesture.touchId    - the Id of the touch which performed the gesture.
+* event.dgesture.gestureId  - the unique id of the closest gesture to the performed stroke.
+* event.dgesture.error      - the difference between the gesture template and the actual performed gesture. Lower error is a better match.
+* event.dgesture.numFingers - the number of fingers used to draw the stroke.
+
+Most programs will want to define an appropriate error threshold and check to be sure that the error of a gesture is not abnormally high (an indicator that no gesture was performed).
+
+
+
+Saving:
+-------
+To save a template, call SDL_SaveDollarTemplate(gestureId, dst) where gestureId is the id of the gesture you want to save, and dst is an SDL_RWops pointer to the file where the gesture will be stored.
+
+To save all currently loaded templates, call SDL_SaveAllDollarTemplates(dst) where dst is an SDL_RWops pointer to the file where the gesture will be stored.
+
+Both functions return the number of gestures successfully saved.
+
+
+Loading:
+--------
+To load templates from a file, call SDL_LoadDollarTemplates(touchId,src) where touchId is the id of the touch to load to (or -1 to load to all touch devices), and src is an SDL_RWops pointer to a gesture save file. 
+
+SDL_LoadDollarTemplates returns the number of templates successfully loaded.
+
+
+
+===========================================================================
+Multi Gestures
+===========================================================================
+SDL provides simple support for pinch/rotate/swipe gestures. 
+Every time a finger is moved an SDL_MULTIGESTURE event is sent with the following fields:
+
+* event.mgesture.touchId - the Id of the touch on which the gesture was performed.
+* event.mgesture.x       - the normalized x coordinate of the gesture. (0..1)
+* event.mgesture.y       - the normalized y coordinate of the gesture. (0..1)
+* event.mgesture.dTheta  - the amount that the fingers rotated during this motion.
+* event.mgesture.dDist   - the amount that the fingers pinched during this motion.
+* event.mgesture.numFingers - the number of fingers used in the gesture.
+
+
+===========================================================================
+Notes
+===========================================================================
+For a complete example see test/testgesture.c
+
+Please direct questions/comments to:
+   jim.tla+sdl_touch@gmail.com

libs/SDL2/docs/README-hg.md

+Mercurial
+=========
+
+The latest development version of SDL is available via Mercurial.
+Mercurial allows you to get up-to-the-minute fixes and enhancements;
+as a developer works on a source tree, you can use "hg" to mirror that
+source tree instead of waiting for an official release. Please look
+at the Mercurial website ( https://www.mercurial-scm.org/ ) for more
+information on using hg, where you can also download software for
+Mac OS X, Windows, and Unix systems.
+
+    hg clone http://hg.libsdl.org/SDL
+
+If you are building SDL via configure, you will need to run autogen.sh
+before running configure.
+
+There is a web interface to the subversion repository at:
+	http://hg.libsdl.org/SDL/
+
+There is an RSS feed available at that URL, for those that want to
+track commits in real time.
+

libs/SDL2/docs/README-ios.md

+iOS
+======
+
+==============================================================================
+Building the Simple DirectMedia Layer for iOS 5.1+
+==============================================================================
+
+Requirements: Mac OS X 10.8 or later and the iOS 7+ SDK.
+
+Instructions:
+
+1.  Open SDL.xcodeproj (located in Xcode-iOS/SDL) in Xcode.
+2.  Select your desired target, and hit build.
+
+There are three build targets:
+- libSDL.a:
+	Build SDL as a statically linked library
+- testsdl:
+	Build a test program (there are known test failures which are fine)
+- Template:
+	Package a project template together with the SDL for iPhone static libraries and copies of the SDL headers.  The template includes proper references to the SDL library and headers, skeleton code for a basic SDL program, and placeholder graphics for the application icon and startup screen.
+
+
+==============================================================================
+Build SDL for iOS from the command line
+==============================================================================
+
+1. cd (PATH WHERE THE SDL CODE IS)/build-scripts
+2. ./iosbuild.sh
+
+If everything goes fine, you should see a build/ios directory, inside there's
+two directories "lib" and "include". 
+"include" contains a copy of the SDL headers that you'll need for your project,
+make sure to configure XCode to look for headers there.
+"lib" contains find two files, libSDL2.a and libSDL2main.a, you have to add both 
+to your XCode project. These libraries contain three architectures in them,
+armv6 for legacy devices, armv7, and i386 (for the simulator).
+By default, iosbuild.sh will autodetect the SDK version you have installed using 
+xcodebuild -showsdks, and build for iOS >= 3.0, you can override this behaviour 
+by setting the MIN_OS_VERSION variable, ie:
+
+MIN_OS_VERSION=4.2 ./iosbuild.sh
+
+==============================================================================
+Using the Simple DirectMedia Layer for iOS
+==============================================================================
+
+FIXME: This needs to be updated for the latest methods
+
+Here is the easiest method:
+1.  Build the SDL library (libSDL2.a) and the iPhone SDL Application template.
+2.  Install the iPhone SDL Application template by copying it to one of Xcode's template directories.  I recommend creating a directory called "SDL" in "/Developer/Platforms/iOS.platform/Developer/Library/Xcode/Project Templates/" and placing it there.
+3.  Start a new project using the template.  The project should be immediately ready for use with SDL.
+
+Here is a more manual method:
+1.  Create a new iOS view based application.
+2.  Build the SDL static library (libSDL2.a) for iOS and include them in your project.  Xcode will ignore the library that is not currently of the correct architecture, hence your app will work both on iOS and in the iOS Simulator.
+3.  Include the SDL header files in your project.
+4.  Remove the ApplicationDelegate.h and ApplicationDelegate.m files -- SDL for iOS provides its own UIApplicationDelegate.  Remove MainWindow.xib -- SDL for iOS produces its user interface programmatically.
+5.  Delete the contents of main.m and program your app as a regular SDL program instead.  You may replace main.m with your own main.c, but you must tell Xcode not to use the project prefix file, as it includes Objective-C code.
+
+==============================================================================
+Notes -- Retina / High-DPI and window sizes
+==============================================================================
+
+Window and display mode sizes in SDL are in "screen coordinates" (or "points",
+in Apple's terminology) rather than in pixels. On iOS this means that a window
+created on an iPhone 6 will have a size in screen coordinates of 375 x 667,
+rather than a size in pixels of 750 x 1334. All iOS apps are expected to
+size their content based on screen coordinates / points rather than pixels,
+as this allows different iOS devices to have different pixel densities
+(Retina versus non-Retina screens, etc.) without apps caring too much.
+
+By default SDL will not use the full pixel density of the screen on
+Retina/high-dpi capable devices. Use the SDL_WINDOW_ALLOW_HIGHDPI flag when
+creating your window to enable high-dpi support.
+
+When high-dpi support is enabled, SDL_GetWindowSize() and display mode sizes
+will still be in "screen coordinates" rather than pixels, but the window will
+have a much greater pixel density when the device supports it, and the
+SDL_GL_GetDrawableSize() or SDL_GetRendererOutputSize() functions (depending on
+whether raw OpenGL or the SDL_Render API is used) can be queried to determine
+the size in pixels of the drawable screen framebuffer.
+
+Some OpenGL ES functions such as glViewport expect sizes in pixels rather than
+sizes in screen coordinates. When doing 2D rendering with OpenGL ES, an
+orthographic projection matrix using the size in screen coordinates
+(SDL_GetWindowSize()) can be used in order to display content at the same scale
+no matter whether a Retina device is used or not.
+
+==============================================================================
+Notes -- Application events
+==============================================================================
+
+On iOS the application goes through a fixed life cycle and you will get
+notifications of state changes via application events. When these events
+are delivered you must handle them in an event callback because the OS may
+not give you any processing time after the events are delivered.
+
+e.g.
+
+    int HandleAppEvents(void *userdata, SDL_Event *event)
+    {
+        switch (event->type)
+        {
+        case SDL_APP_TERMINATING:
+            /* Terminate the app.
+               Shut everything down before returning from this function.
+            */
+            return 0;
+        case SDL_APP_LOWMEMORY:
+            /* You will get this when your app is paused and iOS wants more memory.
+               Release as much memory as possible.
+            */
+            return 0;
+        case SDL_APP_WILLENTERBACKGROUND:
+            /* Prepare your app to go into the background.  Stop loops, etc.
+               This gets called when the user hits the home button, or gets a call.
+            */
+            return 0;
+        case SDL_APP_DIDENTERBACKGROUND:
+            /* This will get called if the user accepted whatever sent your app to the background.
+               If the user got a phone call and canceled it, you'll instead get an SDL_APP_DIDENTERFOREGROUND event and restart your loops.
+               When you get this, you have 5 seconds to save all your state or the app will be terminated.
+               Your app is NOT active at this point.
+            */
+            return 0;
+        case SDL_APP_WILLENTERFOREGROUND:
+            /* This call happens when your app is coming back to the foreground.
+               Restore all your state here.
+            */
+            return 0;
+        case SDL_APP_DIDENTERFOREGROUND:
+            /* Restart your loops here.
+               Your app is interactive and getting CPU again.
+            */
+            return 0;
+        default:
+            /* No special processing, add it to the event queue */
+            return 1;
+        }
+    }
+    
+    int main(int argc, char *argv[])
+    {
+        SDL_SetEventFilter(HandleAppEvents, NULL);
+    
+        ... run your main loop
+    
+        return 0;
+    }
+
+    
+==============================================================================
+Notes -- Accelerometer as Joystick
+==============================================================================
+
+SDL for iPhone supports polling the built in accelerometer as a joystick device.  For an example on how to do this, see the accelerometer.c in the demos directory.
+
+The main thing to note when using the accelerometer with SDL is that while the iPhone natively reports accelerometer as floating point values in units of g-force, SDL_JoystickGetAxis() reports joystick values as signed integers.  Hence, in order to convert between the two, some clamping and scaling is necessary on the part of the iPhone SDL joystick driver.  To convert SDL_JoystickGetAxis() reported values BACK to units of g-force, simply multiply the values by SDL_IPHONE_MAX_GFORCE / 0x7FFF.
+
+==============================================================================
+Notes -- OpenGL ES
+==============================================================================
+
+Your SDL application for iOS uses OpenGL ES for video by default.
+
+OpenGL ES for iOS supports several display pixel formats, such as RGBA8 and RGB565, which provide a 32 bit and 16 bit color buffer respectively. By default, the implementation uses RGB565, but you may use RGBA8 by setting each color component to 8 bits in SDL_GL_SetAttribute().
+
+If your application doesn't use OpenGL's depth buffer, you may find significant performance improvement by setting SDL_GL_DEPTH_SIZE to 0.
+
+Finally, if your application completely redraws the screen each frame, you may find significant performance improvement by setting the attribute SDL_GL_RETAINED_BACKING to 0.
+
+OpenGL ES on iOS doesn't use the traditional system-framebuffer setup provided in other operating systems. Special care must be taken because of this:
+
+- The drawable Renderbuffer must be bound to the GL_RENDERBUFFER binding point when SDL_GL_SwapWindow() is called.
+- The drawable Framebuffer Object must be bound while rendering to the screen and when SDL_GL_SwapWindow() is called.
+- If multisample antialiasing (MSAA) is used and glReadPixels is used on the screen, the drawable framebuffer must be resolved to the MSAA resolve framebuffer (via glBlitFramebuffer or glResolveMultisampleFramebufferAPPLE), and the MSAA resolve framebuffer must be bound to the GL_READ_FRAMEBUFFER binding point, before glReadPixels is called.
+
+The above objects can be obtained via SDL_GetWindowWMInfo() (in SDL_syswm.h).
+
+==============================================================================
+Notes -- Keyboard
+==============================================================================
+
+The SDL keyboard API has been extended to support on-screen keyboards:
+
+void SDL_StartTextInput()
+	-- enables text events and reveals the onscreen keyboard.
+
+void SDL_StopTextInput()
+	-- disables text events and hides the onscreen keyboard.
+
+SDL_bool SDL_IsTextInputActive()
+	-- returns whether or not text events are enabled (and the onscreen keyboard is visible)
+
+
+==============================================================================
+Notes -- Reading and Writing files
+==============================================================================
+
+Each application installed on iPhone resides in a sandbox which includes its own Application Home directory.  Your application may not access files outside this directory.
+
+Once your application is installed its directory tree looks like:
+
+    MySDLApp Home/
+        MySDLApp.app
+        Documents/
+        Library/
+            Preferences/
+        tmp/
+
+When your SDL based iPhone application starts up, it sets the working directory to the main bundle (MySDLApp Home/MySDLApp.app), where your application resources are stored.  You cannot write to this directory.  Instead, I advise you to write document files to "../Documents/" and preferences to "../Library/Preferences".  
+
+More information on this subject is available here:
+http://developer.apple.com/library/ios/#documentation/iPhone/Conceptual/iPhoneOSProgrammingGuide/Introduction/Introduction.html
+
+==============================================================================
+Notes -- iPhone SDL limitations
+==============================================================================
+
+Windows:
+	Full-size, single window applications only.  You cannot create multi-window SDL applications for iPhone OS.  The application window will fill the display, though you have the option of turning on or off the menu-bar (pass SDL_CreateWindow() the flag SDL_WINDOW_BORDERLESS).
+
+Textures:
+	The optimal texture formats on iOS are SDL_PIXELFORMAT_ABGR8888, SDL_PIXELFORMAT_ABGR8888, SDL_PIXELFORMAT_BGR888, and SDL_PIXELFORMAT_RGB24 pixel formats.
+
+Loading Shared Objects:
+	This is disabled by default since it seems to break the terms of the iOS SDK agreement for iOS versions prior to iOS 8. It can be re-enabled in SDL_config_iphoneos.h.
+
+==============================================================================
+Game Center 
+==============================================================================
+
+Game Center integration might require that you break up your main loop in order to yield control back to the system. In other words, instead of running an endless main loop, you run each frame in a callback function, using:
+
+    int SDL_iPhoneSetAnimationCallback(SDL_Window * window, int interval, void (*callback)(void*), void *callbackParam);
+
+This will set up the given function to be called back on the animation callback, and then you have to return from main() to let the Cocoa event loop run.
+
+e.g.
+
+    extern "C"
+    void ShowFrame(void*)
+    {
+        ... do event handling, frame logic and rendering ...
+    }
+    
+    int main(int argc, char *argv[])
+    {
+        ... initialize game ...
+    
+    #if __IPHONEOS__
+        // Initialize the Game Center for scoring and matchmaking
+        InitGameCenter();
+    
+        // Set up the game to run in the window animation callback on iOS
+        // so that Game Center and so forth works correctly.
+        SDL_iPhoneSetAnimationCallback(window, 1, ShowFrame, NULL);
+    #else
+        while ( running ) {
+            ShowFrame(0);
+            DelayFrame();
+        }
+    #endif
+        return 0;
+    }
+
+==============================================================================
+Deploying to older versions of iOS
+==============================================================================
+
+SDL supports deploying to older versions of iOS than are supported by the latest version of Xcode, all the way back to iOS 6.1
+
+In order to do that you need to download an older version of Xcode:
+https://developer.apple.com/download/more/?name=Xcode
+
+Open the package contents of the older Xcode and your newer version of Xcode and copy over the folders in Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/DeviceSupport
+
+Then open the file Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS.sdk/SDKSettings.plist and add the versions of iOS you want to deploy to the key Root/DefaultProperties/DEPLOYMENT_TARGET_SUGGESTED_VALUES
+
+Open your project and set your deployment target to the desired version of iOS
+
+Finally, remove GameController from the list of frameworks linked by your application and edit the build settings for "Other Linker Flags" and add -weak_framework GameController

libs/SDL2/docs/README-linux.md

+Linux
+================================================================================
+
+By default SDL will only link against glibc, the rest of the features will be
+enabled dynamically at runtime depending on the available features on the target
+system. So, for example if you built SDL with Xinerama support and the target
+system does not have the Xinerama libraries installed, it will be disabled
+at runtime, and you won't get a missing library error, at least with the 
+default configuration parameters.
+
+
+================================================================================
+Build Dependencies
+================================================================================
+    
+Ubuntu 13.04, all available features enabled:
+
+sudo apt-get install build-essential mercurial make cmake autoconf automake \
+libtool libasound2-dev libpulse-dev libaudio-dev libx11-dev libxext-dev \
+libxrandr-dev libxcursor-dev libxi-dev libxinerama-dev libxxf86vm-dev \
+libxss-dev libgl1-mesa-dev libesd0-dev libdbus-1-dev libudev-dev \
+libgles1-mesa-dev libgles2-mesa-dev libegl1-mesa-dev libibus-1.0-dev \
+fcitx-libs-dev libsamplerate0-dev libsndio-dev
+
+Ubuntu 16.04+ can also add "libwayland-dev libxkbcommon-dev wayland-protocols"
+to that command line for Wayland support.
+
+NOTES:
+- This includes all the audio targets except arts, because Ubuntu pulled the 
+  artsc0-dev package, but in theory SDL still supports it.
+- libsamplerate0-dev lets SDL optionally link to libresamplerate at runtime
+  for higher-quality audio resampling. SDL will work without it if the library
+  is missing, so it's safe to build in support even if the end user doesn't
+  have this library installed.
+- DirectFB isn't included because the configure script (currently) fails to find
+  it at all. You can do "sudo apt-get install libdirectfb-dev" and fix the 
+  configure script to include DirectFB support. Send patches.  :)
+
+
+================================================================================
+Joystick does not work
+================================================================================
+
+If you compiled or are using a version of SDL with udev support (and you should!)
+there's a few issues that may cause SDL to fail to detect your joystick. To
+debug this, start by installing the evtest utility. On Ubuntu/Debian:
+
+    sudo apt-get install evtest
+    
+Then run:
+    
+    sudo evtest
+    
+You'll hopefully see your joystick listed along with a name like "/dev/input/eventXX"
+Now run:
+    
+    cat /dev/input/event/XX
+
+If you get a permission error, you need to set a udev rule to change the mode of
+your device (see below)    
+    
+Also, try:
+    
+    sudo udevadm info --query=all --name=input/eventXX
+    
+If you see a line stating ID_INPUT_JOYSTICK=1, great, if you don't see it,
+you need to set up an udev rule to force this variable.
+
+A combined rule for the Saitek Pro Flight Rudder Pedals to fix both issues looks 
+like:
+    
+   SUBSYSTEM=="input", ATTRS{idProduct}=="0763", ATTRS{idVendor}=="06a3", MODE="0666", ENV{ID_INPUT_JOYSTICK}="1"
+   SUBSYSTEM=="input", ATTRS{idProduct}=="0764", ATTRS{idVendor}=="06a3", MODE="0666", ENV{ID_INPUT_JOYSTICK}="1"
+   
+You can set up similar rules for your device by changing the values listed in
+idProduct and idVendor. To obtain these values, try:
+    
+    sudo udevadm info -a --name=input/eventXX | grep idVendor
+    sudo udevadm info -a --name=input/eventXX | grep idProduct
+    
+If multiple values come up for each of these, the one you want is the first one of each.    
+
+On other systems which ship with an older udev (such as CentOS), you may need
+to set up a rule such as:
+    
+    SUBSYSTEM=="input", ENV{ID_CLASS}=="joystick", ENV{ID_INPUT_JOYSTICK}="1"
+