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.

Changed, Draw Lines and Draw Curve modes: "Auto-finish drawing" option now works regardless of "Continuous drawing" option (previously it worked only when the latter was enabled). 
Changed: position and size of the "Errors and Warnings" window is now stored while the editor is running.
Internal: rewritten parts of long texture names support code. It now involves much less special handling.
Updated ZDoom_DECORATE.cfg (A_QuakeEx, A_CheckBlock).
Updated ZDoom_ACS.cfg (QuakeEx).
Updated ZDoom ACC (QuakeEx).

Internal: removed some duplicate casts, marked some classes is IDisposable, some streams were disposed more than once.

Game configurations: added 2 secret Sector_Set3dFloor flags. Shhh! Don't tell anybody!

Added, Draw Ellipse mode: angle setting can now be changed using "Rotate Clockwise" and "Rotate Counterclockwise" actions.
Added, Draw Line and Draw Curve modes: added "Auto-finish drawing" setting. When enabled, the modes will automatically finish drawing when currently drawn lines and already existing level geometry form a closed shape.
Changed: sector-wise linedef flipping is now done using the new "Align Linedefs" action. "Flip Linedefs" action works the same as in DB2 again.
Changed: when a map was already loaded, using "Open Map" action will use that map's directory as the starting directory.
Changed: official IWADs can no longer be saved.
Changed: disabled lump ranges/duplicate entries checks for official IWADs.
Changed: wad type is now preserved when saving a map (previously all wads were saved as PWADs).
Changed: moved Updater.exe launch much closer to the editor termination point to avoid any chance of it closing the editor before it properly closes itself.
Updated ZDoom_DECORATE.cfg (A_Blast).
Updated documentation.

Changed, cosmetic: elapsed time is now displayed after resources loading finishes.
Changed, internal: changed Clock.CurrentTime type to long.
Fixed, Tag Statistics window: in some cases the map view was not updated after selecting items in Sectors/Linedefs/Things columns. 
Fixed, cosmetic: Draw Curve mode icon was missing a shadow.

Fixed, Visual mode: in some cases GLDEFS glow effect was not updated after changing floor/ceiling texture.
Fixed, Draw Rectangle and Draw Ellipse modes: in some cases pressing "Reset" button did not update the shape preview.
Fixed, DB2 bug: sector geometry was not updated after undoing "Flip Sidedefs" action.

Fixed, Visual mode: fixed a crash, which happened after these steps: delete things in Classic mode -> undo things deletion in Visual mode -> redo things deletion in Visual mode.

Fixed, DB2 bug, Visual mode: in some cases (sidedef's sector ceiling lower than other side's sector floor) higher/lower sidedef picking was behaving incorrectly.

Fixed, Visual mode: sector geometry was not updated after changing sector brightness under a 3D floor.

Fixed, Texture Browser window: in some cases navigating the textures list using up/down arrows caused an exception.
Fixed, Map Analysis window: fixed an exception on copying warnings to clipboard when the clipboard was used by other application.
Fixed, TEXTURES parser: added special handling for "TNT1A0" sprite name so a texture with this sprite as a single patch is no longer treated as failed loading.
Fixed, Visual mode: in some cases (like line slopes used in several adjacent sectors) sector effect updates were triggered multiple times for the same sector, resulting in noticeable slowdowns and in some cases in infinite recursion.
Updated ZDoom ACC.

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.

Fixed, Visual mode: fixed inability to drag auto-selected sidedef parts using mouse when "Synchronize selection between Visual and Classic modes" setting was enabled.
Fixed, Visual mode: fixed incorrect auto-selected sidedefs texture offset clamping when "Synchronize selection between Visual and Classic modes" setting was enabled.

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, Visual mode: fixed D3DERR_INVALIDCALL error caused by a bug in classic skybox texture creation.
Fixed, Visual mode: aspect ratio was not updated when render area was resized.
Fixed, Visual mode: vertex handles were disappearing after using Reload Resources (F8) action.
Changed, internal: removed most of the fixed pipeline rendering code. The editor can no longer be used on a video card without Shader Model 2.0 support. 

Fixed, Visual mode: "Select with the same texture" action should not select invisible geometry (like sidedef parts hidden by slopes).
Changed, Sector drawing: default sector height is now used when the nearest sector's height is <= 0.

Fixed, Visual mode: "render as sky" flag was not updated for upper wall geometry when pasting textures (and in some other cases).

Added "Toggle sky rendering" action and toolbar button.
Added, MAPINFO parser: the editor now recognizes map number from classic map definition format. Hexen MAPINFO is now properly parsed.
Added, MAPINFO support: if current map definition contains map name as a text string, it will be shown in the editor's header.
Changed: "Toggle dynamic lights rendering" now toggles between "Don't show dynamic lights" and "Show dynamic lights" when used in Classic modes. 
Changed, Things mode: lowered the opacity of dynamic light radii.
Changed, (G)ZDoom text parsers: empty include files now trigger a warning instead of an error and no longer abort parsing.
Fixed, Game configurations: moved Stalagmite:5050 thing to Doom block (so the editor no longer tries to load it for non-Doom game configurations).
Fixed(?), Visual mode: probably fixed a hard-to-trigger exception when sorting translucent geometry.
Fixed, Visual mode: floor glow effect was incorrectly applied to walls (was broken in R2452).
Internal: restructured most of MAPINFO and GLDEFS parsers. Should be more maintainable now.  
Updated ZDoom ACC.
Updated zdbsp to 1.19.
Updated documentation.

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.

Updated ZDoom ACC and ZDoom_ACS.cfg (added GetInventoryMax()).

Changed, "Select Similar", "Paste Properties Special" actions properties windows, Linedefs: removed "Sidedef Properties" from Linedef flags tab.
Fixed several issues with "Synchronized Things Selection" setting:
- Things were not deselected after dragging a single sector.
- Things were not deselected after editing properties of a single sector.
- Things sector references were not updated after using "Join Sectors" and "Merge Sectors" actions.
- Things (de)selection is now applied to all things, instead of only the ones visible using current Things Filter.

Cosmetic, actions: renamed "Lower Floor/Ceiling by 8 mp" to "Lower Floor/Ceiling/Thing by 8 mp", "Raise Floor/Ceiling by 8 mp" to "Raise Floor/Ceiling/Thing by 8 mp", "Lower Floor/Ceiling by 1 mp" to "Lower Floor/Ceiling/Thing by 1 mp", "Raise Floor/Ceiling by 1 mp" to "Raise Floor/Ceiling/Thing by 1 mp", "Lower Floor/Ceiling to adjacent sector" to "Lower Floor/Ceiling/Thing to adjacent Sector/Thing", "Raise Floor/Ceiling to adjacent sector" to "Raise Floor/Ceiling/Thing to adjacent Sector/Thing".
Updated, Visual mode, "Raise Floor/Ceiling/Thing to adjacent Sector/Thing" / "Lower Floor/Ceiling/Thing to adjacent Sector/Thing" actions: sectors across targeted sectors are now taken into account when determining target height.
Updated, Visual mode, "Raise Floor/Ceiling/Thing to adjacent Sector/Thing" / "Lower Floor/Ceiling/Thing to adjacent Sector/Thing" actions: the actions can now stack things on top of other things when their bounding boxes intersect. 
Internal: cosmetic changes to shader update logic.
Internal: thing bounding box is now used when adding a thing to VisualBlockMap.

Fixed, Visual mode: fixed a crash when showing Edit Vertex window when several selected vertices belonged to the same sector.

Fixed, Visual mode: in some cases fog density of 3d floor floors/ceilings was calculated incorrectly. 

Fixed, Visual mode, "Auto-align textures" actions, UDMF: vertical offsets of non-wrapped middle textures should not be clamped.
Fixed, Visual mode: brightness of 3d floors with "disable lighting" flag was calculated incorrectly.
Fixed, Sectors mode: 3d floor linedef indicators were not updated after using "Join Sectors" and "Merge Sectors" actions.

Fixed, Visual mode, fog rendering: things with Bright setting should still be affected by custom fade.
Updated ZDoom_DECORATE.cfg.

Fixed, Visual mode: fixed incorrect GLDEFS glow brightness calculation for Things.
Updated ZDoom_DECORATE.cfg.

Fixed, Script Editor, cosmetic: we should not show error line number when we don't have one.
ZDoom acc.exe: several error types now output more detailed info.
Fixed, Visual mode: UDMF thing alpha property was applied only when UDMF renderstyle property was also set (should also be applied when renderstyle property is set in the DECORATE actor definition).
Game configurations, ZDoom family: Pistol and Gold Wand actors now use internal sprites.
Updated ZDoom ACC and ZDoom_ACS.cfg (PickActor flags).

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.

Fixed, Visual mode, UDMF: incorrect texture name was copied when using "Copy Texture" action when copying a texture stored in a folder resource when "Use long texture names" settings was enabled.

Fixed, Script Editor: in some cases includes list was not updated before trying to compile the script leading to compilation failure.
Changed, ACC compiler: when building includes list, the compiler no longer tries to find/copy include files defined in current script configuration (previously it was hardcoded to skip "zcommon.acs" and "common.acs" only).
Fixed, Visual mode: things with Additive RenderStyle were rendered as additive only when their alpha was less than 1.0.

Fixed, Visual mode: fixed a crash when trying to render a Thing with translucent or additive renderstyle outside of any sector.
Fixed, Classic modes: 3d floor linedef indicators shown in Classic modes were not updated after finishing sector drawing.
Updated ZDoom ACC to git rev. f92fbb9.
Updated ZDoom_ACS.cfg.

Fixed: 3d floor linedef indicators shown in Classic modes were not updated when 3d floor creation was undone in Visual mode.
Performance optimization when selecting sectors in Sectors mode with "Synchronized Things selection" setting enabled. 

Sectors mode: removed "Move Things in Selected Sectors" toolbar button.
Sectors mode: added "Synchronized Things Editing" menu item, action and toolbar button. When enabled, things dragging will be synchronized to sector dragging. Regular, Paint and Rectangular selection will also select things (holding Alt while selecting inverts this behavior). Deleting sectors will also delete selected things.
Linedefs mode: added "Synchronized Things Editing" menu item, action and toolbar button. When enabled, selected things will be dragged when dragging linedefs. Rectangular selection will also select things (holding Alt while selecting inverts this behavior).
Changed: selection info now always displays info about all types of map elements.
Fixed: .dbs containing only current map settings was created when trying to save unchanged map. 
Fixed, Visual mode, "Copy Texture" action: when "Use long texture names" option is disabled, texture name as stored in Sidedef should be used, not the 8-char texture name.
Updated documentation.

Added "makedoorceil" game configuration property. Works the same way as "makedoortrack" and "makedoordoor", but for ceilings of door sectors. 
Changed, Game configurations: the editor no longer tries to load DECORATE/MODELDEF/VOXELDEF/GLDEFS/REVERBS lumps when "decorategames" setting is not specified / is set to empty string.
Changed, General interface: "Tools -> Reload MODELDEF/VOXELDEF" and "Tools -> Reload GLDEFS" menu items are no longer shown when current game configuration doesn't support DECORATE. 
Fixed a crash when pasting linedef/thing properties in Hexen map format.
Fixed, Visual mode: Visual Thing resources were not fully unloaded when resetting D3D device leading to crash when switching to the editor from a DX-using game engine (like ZDoom) running in fullscreen.
Fixed: in some cases, when current game configuration supported multiple script compilers, it was possible to open/create a map or change map options without selecting any script compiler.
Fixed, New Map Options window: default map name was not updated when switching game configurations.
Fixed: copied map element properties were not reset after switching to another map.
Fixed: stored textures for "Make Door" action were not reset after switching to another map.
Fixed, Game Configurations window: currently selected test engine name was not updated when pasting test engines from another configuration. 
Fixed, Game Configurations: all "Heretic in Doom map format" configurations were using Doom sector effects list.
Fixed, Game Configurations: all "Strife in Doom map format" configurations were using Doom sector effects list.