Fixed, Sectors mode, UDMF: surface cache was not updated after applying floor/ceiling brightness gradients.
Cosmetic, Sectors mode, UDMF: brightness gradient modes now have more descriptive names.
Internal, InterpolationTools: replaced EaseInOutSine equation with one, which actually works.

Sectors mode: "Gradient Interpolation Mode" toolbar menu.
Internal: extracted easing functions from Bridge Mode into InterpolationTools class.
+a couple of cosmetic changes.

Fixed: texture coordinates interpolation during linedef splitting was failing in UDMF map format when target sidedef's texture was in a sub-folder of a PK3 or Folder resource.

Visual mode, "Raise/Lower Sector to Nearest" actions: both floor and ceiling heights of adjacent sectors are now taken into account.

Fixed (DB2 bug): the first texture of every TEXTURE1 lump should be ignored, not the first texture loaded from the first map resource. Also, said texture(s) are no longer shown in the Textures browser.
Cosmetic update in ZDoom_DECORATE.cfg.

+a couple of cosmetic changes.

Fixed, Fit Textures action: sidedefs were not sorted properly when trying to use the action on several disconnected sidedef strips with the same texture.
Fixed, Fit Textures action: update was not triggered when toggling "Fit across connected surfaces" check-box.

Map Analysis mode: selection color is now used when rendering affected things.
Fixed, Map Analysis mode, "Check unused things" check: checker returned false-positive results when used in Doom map format.

Nodes Viewer mode: added more boilerplate to classic nodes reader.
Thing Filters Form: program configuration was not marked as changed when saving thing filters.
Cosmetic layout fixes in Thing/Linedef/Sector Info panels.
Cosmetic text fixes in several Map Analysis results.
Internal: debug console is now cleared when creating a new map.
Updated ZDoom_DECORATE.cfg.

Changed, "Snap selected map elements to grid" action: the action now works on any selected map element type.
Fixed, Sectors mode: holding Alt to (de)select things inside of sectors worked only in band selection mode. Now it also works when selecting individual sectors and when using paint selection mode.
Fixed, Statistics Control: forgot to remove some test code in r2176...
Internal: removed several unused icons.

Statistics control: relevant labels now turn red when current number of given map elements exceeds current map format's maximum.
Statistics control: things count was not updated when adding or deleting things.
Map Analysis mode: "Check texture alignment" is now disabled by default.
Updated Inno Setup script and images.
Added DirectX web installer to Builder\Setup.
Updated MakeRelease.bat.
Updated ZDoom_DECORATE.cfg.

Fixed, Linedef Edit form (classic): it was impossible to enable disabled front/back sides, because corresponding check-boxes were inside of corresponding groups.
Fixed, Nodes Viewer Mode: the mode was unable to handle missing node lumps properly.
Fixed, Nodes Viewer Mode: the mode no longer builds nodes when unable to find both classic nodes and ZNODES at the same time.
Removed SlimDX installer, because it's no longer required.
Internal: debug console is now cleared when opening a map.

High-Dpi: redesigned Docker control's Pin button. Now it is rendered properly when using high-dpi display settings.

DECORATE parser: added multiple actions per frame (http://zdoom.org/Changelog/7d0faa5bd5f39f1b5c721e8287f94dc04811a355/files) support.

Fixed, Visual mode, "Move Texture Up/Down/Left/Right" actions: sidedef textures were moved several units at once when several sidedef parts were selected in Doom and Hexen map formats.

Fixed, Visual Mode: untextured middle parts of double-sided linedefs were selected when Shift-selecting a sidedef part with missing texture ("-").

Map Analysis mode: added "Browse Texture" fix to "Missing Texture" and "Unknown Texture" error results.
Map Analysis mode: added "Browse Flat" fix to "Missing Flat" and "Unknown Flat" error results.
Fixed several typos in ZDoom_misc.cfg.

High-DPI: fixed alignment issues in Sector, Thing, Linedef and Vertex Edit Forms, also in Open Map Options and Map Options Forms.
Changed: Thing Browser Form is now resizeable.
Changed: made default Texture Browser Form size smalled, so it properly fits the screen when using low display resolution.

Linedef Edit Form (Doom/Hexen map formats): fixed incorrect window size when using low display resolution (like 1024x768).

DECORATE parser: added special handling for ZDoom's special sprite names (namely TNT1, "####" and "----").
Internal: changed the way apppath is acquired. It should no longer fail when launching the editor from a shared network folder.
Main Form: changed some labels of dynamic light and model rendering selectors to be less confusing.
Updated ZDoom_DECORATE.cfg.

Internal: moved TNT1A0 ignoring logic to a more adequate place (why these "proper implementation" ideas always occur right AFTER I commit stuff?..)

Updated ZDoom_DECORATE.cfg. 

High-DPI: added app.manifest, which enables application DPI-awareness.
High-DPI: ExceptionDialog is now displayed properly.

Apparently, we can no longer load a map named "MAP" after r2151. Let's warn a user about this unfortunate event.

Added more checks and fixed incorrect flag assignment in UDMF -> Hexen action conversion from r2155. 

Updated SharpCompress library from 0.8.1 to 0.10.3. This fixes inability to load certain PK7 files and grants a 2x performance boost when loading PK3 and PK7 files.

Added Hexen -> UDMF and UDMF -> Hexen action conversion as described in "Universal Doom Map Format ZDoom extensions" (udmf_zdoom.txt). It is used when changing map format form Hexen to UDMF and from UDMF to Hexen.
Game configurations, Line Identification action: added "Front side only" (128) flag to arg1.
Game configurations, Line Identification action: renamed arg1 flags to match corresponding UDMF flag names.
Updated udmf_zdoom.txt.

Fixed: PairedFloatControl had incorrect initial link icon.
Internal, AngleControl: rewritten AngleChanged event so it behaves like the rest of custom events.
Updated GZDB icon.

Find and Replace mode: only used sidedef parts are now found when searching for missing texture ("-").
Find and Replace mode: only textures on used sidedef parts are now replaced when replacing missing texture ("-"), 

Fixed, Fit Textures action: vertical texture offset of a middle part of double-sided linedef with "Lower unpegged" flag was calculated incorrectly.
Fixed, Fit Textures action: texture offsets were calculated incorrectly when using the action on several groups of connected walls at once with "Fit across connected surfaces" enabled.
Fixed, Visual mode: middle parts of double-sided linedefs were not rendered when ScaleY was negative.
Updated ZDoom_DECORATE.cfg.

Visual mode: "Fit Textures" action can now fit textures across multiple selected surfaces. A number of times to repeat a texture can now be specified.  
Visual mode: removed "Fit Texture's Width" and "Fit Texture's Height" actions.
Visual mode: "Auto-align texture offsets" actions were incorrectly aligning double-sided middle walls in some cases.
Visual mode: "Auto-align texture offsets" actions now align non-wrapped double-sided middle walls to vertical offset closest to their initial vertical offset.
Visual mode: middle parts of double-sided walls were ignored when Shift-selecting walls.
Nodebuilders/Game configurations: GL nodes definitions were missing from game configurations.
Nodebuilders/Game configurations: "~MAP" wildcard can now be a part of a lump name. 
Nodebuilders: GL nodes were not properly handled by the editor.
Main Window: the window is now moved into the view when stored position is ouside of screen bounds. 
Classic and Visual modes: changing thing pitch was ignored in some cases.
Visual mode: raising and lowering a thing with "+SPAWNCEILING" flag now works the same way as when raising/lowering a regular thing.
Visual mode: using "Raise/Lower Floor/Ceiling to adjacent sector" actions on a thing with "+SPAWNCEILING" flag now works the same way as when using them on a regular thing.  
Rendering: even more fixes to MODELDEF and UDMF properties-related model rendering logic.
Internal, ResourceListEditor: rewritten resource validation check in a more OOP-ish way.
Configurations: fixed an infinite loop crash when a file was trying to include() itself.
UDMF thing flags: added Skill 6-8 to the flags list (because there are thing filters for these).
ZDoom_ACS.cfg: added definitions for SetTeleFog and SwapTeleFog.
ZDoom_DECORATE.cfg: added definitions for A_SetTeleFog and A_SwapTeleFog.
Updated ZDoom ACC.
Updated documentation.

Resource List Editor: not existing resources are now shown using different color. 
Map Options, Open Map Options, Game Configurations windows: a warning is now shown when a map resource doesn't exist.
Some minor fixes to Resource List Editor's context menu.
Updated ZDoom_DECORATE.cfg.

Resource List Editor: fixed potential crash on pasting/replacing resources when there are duplicate resources in the list.
Resource List Editor: duplicate resources are no longer added when adding resources using drag and drop.

Resource List Editor now has a context menu.
Fixed misleading warning asking user to install DirectX when unable to detect SlimDX.