Added, Visual mode: added "Toggle Alpha-based Texture Highlighting" action. When enabled, 3d floor textures and middle textures on double-sided lines will be highlighted only when the crosshair points at a non-transparent pixel.
Changed: multi-part sectors are now better preserved after drawing new lines.
Changed, TEXTURES parser: patch loading errors are now ignored for textures with "NullTexture" option.
Changed, Game configurations: changed default door action arguments to better match vanilla ones.
Fixed, Actions: in some cases keyboard shortcuts involving Ctrl/Alt/Shift modifier keys were displayed incorrectly.
Fixed(?): probably fixed inability to save map wad in Slade 3.
Updated ZDoom_ACS.cfg.
Updated ZDoom_DECORATE.cfg.
Updated ZDoom ACC.

Fixed, Visual mode: alpha-based texture picking didn't work correctly on HiRes images.
Fixed, Visual mode: fog density was calculated incorrectly for things lit by dynamic lights.
Fixed, Edit Sector window, UDMF: "Fade" and "Light" color pickers initial values were incorrect when displaying mixed values.
Fixed, Edit Thing window, UDMF: "Color" color picker initial value was incorrect when displaying mixed values.

Added, Visual mode: "Raise/Lower Floor/Ceiling to adjacent Sector" actions now take surrounding 3d floors into account.
Added, Visual mode: highlight/selection based on texture alpha now works on 3d floors.
Changed, Game configurations, TranslucentLine:208 action: renamed the second argument from "Translucency Amount" to "Opacity".
Internal, documentation: updated udmf_zdoom.txt.

Fixed, Visual mode: in some cases ceiling glow effect was interfering with Transfer Brightness effect resulting in incorrectly lit sidedef geometry.
Fixed, Visual mode: UDMF sidedef brightness should be ignored when a wall section is affected by Transfer Brightness effect.
Fixed, Visual mode: any custom fog should be rendered regardless of sector brightness. 
Fixed, Visual mode: "fogdensity" and "outsidefogdensity" MAPINFO values were processed incorrectly.
Fixed, Visual mode: in some cases Things were rendered twice during a render pass.
Fixed, Visual mode: floor glow effect should affect thing brightness only when applied to floor of the sector thing is in.
Fixed, TEXTURES parser: TEXTURES group was named incorrectly in the Textures Browser window when parsed from a WAD file.
Fixed, MAPINFO, GLDEFS, DECORATE parsers: "//$GZDB_SKIP" special comment was processed incorrectly.
Fixed, MAPINFO parser: "fogdensity" and "outsidefogdensity" properties are now initialized using GZDoom default value (255) instead of 0.

Updated skybox model to better match GZDoom's skybox. Also the sky texture was flipped horizontally.
Fixed, Visual mode: "Select with the same texture" action is now able to select sidedef parts only visible because of slopes.
Fixed, Visual mode: skybox texture was not updated after using "Open map in current wad" action.
Fixed, Visual mode: in some cases Visual camera was placed below sector's floor when "Sync camera position between 2D and 3D modes" setting was enabled.
Fixed: numeric thing flags with inverted UDMF flag defined in "thingflagstranslation" Game configuration block were lost when copy-pasting a thing.
Fixed, command line arguments: fixed a crash when loading a map from a wad with existing .dbs file.

Fixed, Map Analysis mode, "Check stuck things" check: rewritten parts of the flags checking logic to allow more accurate flag checks.
Fixed, Map Analysis mode: fixed a crash when trying to dissolve an invalid sector when one of it's linedefs referenced it on the both sides.
Fixed, Sectors mode: fixed incorrect undo description when deleting sectors.
Internal: joined declaration and assignment of some more variables.

Visual mode: rewritten most of the 3d floor clipping and light/color assignment logic. As a result, 3d floors should look much closer to what's seen in GZDoom.
Fixed, Visual mode: glow effect was not updated when changing sector textures using the "Select Texture" action.
Browse Textures/Flats window: when textures list is focused, you can now start typing to change the Filter.

Added "Paste Properties Special" actions in "Classic" and "Visual" categories. They work the same way as "Paste Special" action.
Added: "Copy Properties", "Paste Properties" and "Paste Properties Special" options are now shown in the Edit menu if current classic mode supports them.
Changed, Paste Properties Special window: only options relevant to current map format are now displayed.
Changed, Paste Properties Special window, UDMF: all UI-managed options are now available.
Fixed: MAPINFO parser was unable to process "include" directives.
Fixed, General interface: selection info was reset to "Nothing selected" after few seconds regardless of current selection.
Fixed, Visual mode: thing bounding boxes were not updated when changing things positions using Randomize mode.
Fixed, Visual mode: event lines were displayed at incorrect height when entering Visual mode for the first time.
Fixed, Texture Browser window: when MixTexturesFlats Game Configuration option is disabled, textures/flats are no longer shown in the Used group when flats/textures with the same names are used in the map. 
Fixed(?): probably fixed an exception some users reported when trying to initialize a Classic mode after switching from Visual mode with "Sync cameras" option enabled.
Changed, Game configurations, Thing Categories: a block must have at least one thing category property to be recognized as a thing category.
Changed, Visplane Explorer: the plugin now outputs more info when it fails to initialize vpo.dll.
Cosmetic, Thing Edit window, Doom/Hexen map format: adjusted UI layout so thing flags control no longer displays scrollbars in Hexen map format.
Internal: merged methods from UDMFTools into UniFields, removed UDMFTools. 
Updated Inno Setup script (added VC++ 2008 SP1 distributive). 
Updated ZDoom_DECORATE.cfg (A_CheckBlock).
Updated documentation (added "System Requirements" page).

Visual mode: fog distance calculation is now much closer to GZDoom one.
Visual mode: thing brightness calculation when a thing is affected by floor glow is now much closer to GZDoom one.
Linedef edit window, UDMF: added "Reset front/back brightness" buttons.
Sector edit window, UDMF: added "Reset ceiling/floor brightness" buttons.
Internal, Visual mode, Things mode: persistent event lines are now updated only when map objects are changed instead of doing it on every display redraw.
Internal: improved Dictionary lookup times when using map objects and textures as keys.
Internal: added "Release + Profiler" solution configuration.
Updated ZDoom_ACS.cfg (Warp).

Fixed, Visual mode: double-sided middle texture highlighting transparency check didn't take TEXTURES scaling into account.
Fixed, long texture names: textures located in a directory/pk3/pk7 root can't have long texture names.
Fixed, texture selector controls, long texture names: both long and short texture names should be added to texture name auto-completion list. 
Changed: "Grid Increase" and "Grid Decrease" actions can now be bound to mouse wheel.

Fixed, Visual mode: texture coordinate generated to test if double-sided middle texture is transparent was shifted 1 pixel up.
Fixed, Visual mode: offsets of GLDEFS lights were not affected by thing's angle.
Updated SharpCompress (0.10.3 -> 0.11.1).
Updated ZDoom_DECORATE.cfg.

Fixed, Visual mode, since r2336: in some cases local vertical texture offset was calculated incorrectly when checking sidedef's texture alpha.

Changed, Linedef Edit window, Visual mode, UDMF: when "Edit windows remember selected tabs" setting is enabled and Front or Back tab was previously selected, the tab, which corresponds to the highlighted side will be selected.

Fixed, long texture names support: in some cases long texture names were not processed correctly when pasting map geometry.
Fixed, Visual mode: in some cases combined sidedef brightness was calculated incorrectly. Also, MAPINFO FadeColor and OutsideFogColor properties are now taken into account.
Hexen_linedefs.cfg: "Door Raise" and "Door Locked Raise" used incorrect enums for "Close Delay".

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.

Fixed, Texture Browser Form: well, I broke "Tab" key functionality again (in previous commit)...
Maintenance: changed curly braces style to match DB2 one (hopefully not breaking anything in the process...).
Maintenance: changed private method names casing to match DB2 one.

Fixed, WavefrontExporter: floor and ceiling textures were not exported when using "classic" game configurations (ones with disabled "MixTexturesAndFlats" option). This should also fix incorrect flats on exported model when there are flats and textures with the same name.
Fixed, WavefrontExporter: 3d floors geometry and wall geometry around them was created incorrectly.
Fixed, WavefrontExporter: floor and ceiling textures of non-Vavoom 3d floors were swapped on exported geometry.

Added: Map Analysis: added "Check texture alignment" check. Currently it works only in Doom/Hexen map formats.

Linedef Edit Form, Sector Edit Form: when several map elements with different textures are selected, the "texture stack" icon is shown in the texture selectors instead of the "missing texture" icon.
Error Checker mode: added "Check missing flats" check.
Error Checker mode: fixed several descriptions. 
Sprite patches for sprites defined in TEXTURES are now loaded from Sprites namespace.
Some of my older texture alignment code didn't work properly when strict texture/flat handling ("mixtextureflats" game configuration flag set to false) was enabled.
Fixed some incorrect checks for missing texture ("-").

Game configurations: added "fixedrotation" property to dynamic lights, which use the angle property as a parameter.
Maintenance: removed a ton of redundant stuff.

Error checks: added "Check unused textures" option.
Replaced MissingTexture3D and UnknownTexture3D.
Sectors mode: restored "Lower/Raise Floor/Ceiling by 8 mp" actions.
Visual mode: in some cases sidedefs were rendered as selected when they were not.
Existing linedefs were not split while drawing new lines in some cases.
Texture and height overrides were not applied correctly in some cases.
Preferences form: "Ctrl+Alt+ScrollUp" and "Ctrl+Alt+ScrollDown" dropdown items were setting the shortcut to "Ctrl+Shift+ScrollUp" and "Ctrl+Shift+ScrollDown".

Visual mode: offsets of double-sided middle textures were still clamped when not required in some cases.
Updated documentation.

Visual mode: fixed a crash when trying to move texture offsets of invisible sidedef.

UDMF fields, handled by UI, had broken field types after r1758.
Removed some redundant type casts.

ACS support: script numbers/names without space between them and script arguments (like 'script 999(void)' or 'script "test"(void)') were not parsed.

Visual mode: texture offsets are now clamped to texture size when dragging textures with mouse.
Visual mode, UDMF: when gravity is enabled, sector gravity now affects camera movement.

Textures were not loaded properly from PK3/PK7 archives.
Visual mode: restored ability to remove textures using Delete action.
Visual mode: fixed several bugs in Cut/Copy/Paste things actions.
Visual mode: vavoom style 3d floors were not displayed properly.
Visual mode, 3d floors: added support for "RestrictLighting" (2) flag.
Visual mode, 3d floors: inner sides of 3d floors with "swimmable"/"render inside" flags used incorrect brightness value.

Texture scale controls now have "Link" button. 
Thing, Sector (UDMF) and Linedef edit forms now work in realtime mode.
Some more fixes in Edit form realtime update stuff.
Removed some unused variables and functions.

Visual mode, UDMF: OffsetX and OffsetY were not properly taken into account in "Fit Texture Width/Height" actions.
UDMF: different Sector Edit Form is now used in UDMF map format.
Some fixes in Linedef edit form.
Added missing icons.

Visual mode, UDMF: added "Scale Texture Up (X)", "Scale Texture Down (X)", "Scale Texture Up (Y)", "Scale Texture Down (Y)" actions. Default keys are Num6, Num4, Num8, Num5.
Visual mode, UDMF: renamed "Rotate Thing Clockwise" and "Rotate Thing Counterclockwise" actions to "Rotate Clockwise" and "Rotate Counterclockwise". These actions can now be used to change rotation of floor/ceiling textures.
Visual mode, UDMF: "Reset Texture Offsets" action now also resets sidedef's scale and floor/ceiling's scale and rotation.
Visual mode, UDMF: control line's OffsetX and OffsetY were not taken into account when calculating texture offsets of 3d floors' sides.
Visual mode, UDMF: fixed a ton of bugs in Auto align functions.
Visual mode, UDMF: when using "Move Texture Left/Right/Up/Down by 1" actions texture offsets were not updated properly when texture's scale was < 1.0.
Visual mode, UDMF: OffsetX and OffsetY were not taken into account in "Fit Texture Width/Height" actions.
Dockers Panel: added Pin/Unpin button, which acts the same as "Preferences -> Interface -> Side panels -> Auto hide" checkbox.
Texture size labels can now be disabled by unchecking "Preferences -> Interface -> Show texture and flat sizes in browsers" checkbox.
Texture size labels now are not shown for unknown textures.
Most of texture size labels had incorrect bg color.
ZDoom_linedefs.cfg: action specials 223 and 224 had incorrect Arg0.

Visual Mode, UDMF: added "Fit Texture", "Fit Texture's Width" and "Fit Texture's Height" Actions.cfg
Visual Mode, UDMF, Visual Vertices: you can now press "Delete" key to clear z-offsets of selected vertices.
Visual Mode, UDMF, Visual Vertices: the logic, which decides whether z-offset should be kept or removed, was not working properly.
Visual Mode, UDMF: Auto-align Textures (Y) action was not working properly when targeted texture was lower wall without "Lower Unpegged" flag.

Visual Mode: You can now Shift-Select (usually Select = LMB) to select all adjacent surfaces with same texture, Ctrl-Select to select all adjacent surfaces with same height.
Added Selection Groups options to Edit menu.
Selection Groups can now be cleared using either Edit -> Clear Group or Ctrl-Shift-[group number] shortcut.
Toolbar button groups can now be toggled using context menu. Hold "Shift" to toggle several button groups at once.

Merged Visual mode and GZDoom Visual mode into GZDB Visual mode. GZDoomEditing.dll is no longer required.

Added UDMF Controls plugin.
Added "Snap selected vertices to grid" mode (Found in Edit menu).

Doom-style walls shading is now applied in Visual Mode