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.

Changed, Visual mode: changed thing fog calculation logic. Should be closer to GZDoom now.
Fixed, GLDEFS parser: "height" texture parameter was not treated as optional.
Fixed, text lump parsers: in some cases incorrect line number was displayed in error and warning messages.
Fixed, Visual mode: glow effect was not applied to sectors with 3 sidedefs.
Fixed, Visual mode: in some cases glow effect was not updated when replacing textures. 
Fixed, general interface: "Full Brightness" button state was not updated during map loading.
Fixed, Drag Linedefs/Vertices/Sectors/Things modes: positions of line length labels were not updated while panning the view.
Cosmetic: added a bunch of new icons.
Cosmetic: changed Visual mode crosshair.

Changed, Drag Linedefs/Vertices/Sectors/Things modes: line length labels are now displayed the same way as in Draw modes.
Changed, Drag Linedefs/Vertices/Sectors/Things modes: "lock movement to cardinal directions" mode (Alt-Shift-Drag) now locks movement in 4 directions instead of 8 and doesn't snap map elements to nearest grid intersections when they are not aligned to it. 
Added, Visual mode, GZDoom, DECORATE: FORCEXYBILLBOARD flag is now supported.
Added, Visual mode, GLOOME, DECORATE: FLOORSPRITE, CEILSPRITE, WALLSPRITE, ROLLSPRITE and STICKTOPLANE flags are now supported (implementation is somewhat broken ATM and probably doesn't work the same way as in GLOOME, because Windows build with most these features is nowhere to be found...).
Fixed, Visual mode: in some cases Thing brightness was calculated incorrectly.
Updated ZDoom_DECORATE.cfg.

Changed, Draw Lines/Rectangle/Circle/Curve modes: line length labels are now repositioned to stay on screen when line's start or end is not visible.
Added, Map Analysis mode: added "Check map size" check. It will generate a warning when map's width or height is larger than 32767 m.u.

Added, Things mode, Visual mode: event lines for InterpolationPoints are now curved when appropriate setting is enabled in the control thing (PathFollower/ActorMover/MovingCamera) [heavily inspired by Xabis' patch].
Added, Things mode: the editor will try to reconnect the path when deleting InterpolationPoints and PatrolPoints.
Internal: RenderArrows method now works the same way in Renderer2D and Renderer3D.
Internal: Line3D now has "renderarrowhead" property.

Added, Things mode: target tags are now automatically assigned when duplicating (shift-dragging) PatrolPoints and InterpolationPoints.
Fixed, ThingsMode: fixed highlighted thing disappearing when using paste action while highlighting a thing.

Classic modes: added "Toggle Grid" action (default key is Alt-G), new menu item in the View menu and new toolbar button.
Changed, Things mode, cosmetic: tweaked thing sprite/bounding box appearance a bit more...
Fixed, Linedefs mode, cosmetic: fixed event lines and sector highlights flickering when view panning was started while displaying action highlight.

Changed, Things mode: things are now rendered with a bit of transparency, so things beneath other things are now visible.
Fixed, Things mode: in some cases it was impossible to highlight a thing beneath other thing when their positions were the same.
Changed, 2D modes: changed thing bounding box and arrow image.
Fixed, cosmetic, 2D modes: in some cases thing arrows were rendered bigger than thing bounding boxes.

UDMF: most of the code now supports multiple sector/linedef tags ('moreids' UDMF property). The only things left out are Tag Explorer and Tag Range plugins.

Fixed, Edit Selection mode: "High precision positioning" setting was set to false after using the mode in non-UDMF map format.

Fixed, Classic modes, Visual mode, UDMF: the last argument of Sector_Set3dFloor (160) action must be ignored in UDMF.

General interface: selection info is now always displayed.
Visual mode: you can now hold Alt-Shift or Ctrl-Alt while selecting sidedefs to stop selecting connected sidedefs when already (un)selected sidedef is encountered.
Added, Numeric Textbox: you can now use "+++" and "---" prefixes to incrementally increase or decrease result values by given value.
Fixed, Numeric Textbox: fixed a potential divide by zero exception when using "/" prefix in numeric textboxes with decimal input enabled.
Fixed, Thing Info panel: relative z position of things with "+SPAWNCEILING" flag was incorrect.
Changed: Update checker now displays messages using MessageBoxes when called manually.
Map Analysis: changed result descriptions for Unknown Texture and Missing Texture checks.
Doom map format: renamed "Secret" linedef flag to "Shown as 1-sided on automap".
Updated ZDoom_DECORATE.cfg (A_RadiusGive stuff).

Added some boilerplate to CommentsDocker.
Internal: converted a bunch of if-elses to switches.

Sectors, Linedefs, Things modes: comment icons for appropriate map elements with comments are now rendered in these modes. This can be disabled using either the new "Toggle Comments" action, "View -> Show Comments" menu item, or "Show Comments" button on the main toolbar.

Changed, Edit Text window: the form is no longer accepted when pressing the Enter key, so line breaks can now be added easily.
Versioning: GZDB version is now determined by the first 2 revision digits, so now it's GZDB 2.3, not 1.14.

Map Analysis mode: added "Check very short linedefs" check (unchecked by default), which finds linedefs shorter than 1 m.u.
Fixed: script editor must be closed during "Open map in current WAD" action.
Added: PNG offsets are now taken into account when loading sprites.

Changed: current 2D position and zoom is now stored in the .dbs file when saving the map and restored when opening it (should this be turned into toggleable option?).
Draw Lines mode, Draw Curve mode: you can now hold Alt - Shift to snap to 8 cardinal directions.
Draw Rectangle mode, Draw Grid mode: you can now hold Alt - Shift to draw square shapes.
Draw Ellipse mode: you can now hold Alt - Shift to draw circle shapes.
You can now hold Alt - Shift to snap to 8 cardinal directions while dragging map objects.
Fixed, Draw Lines mode: line angle is now displayed in 0..359 range (was -45..314).
Fixed, Linedef info panel: line angle is now displayed in 0..359 range (was -45..314).

Changed, Sound Environments mode: previously selected sound environment is now automatically selected when inserting a new sound environment item. Also it's now impossible to accept the form without selecting a sound environment.
Changed, Sound Propagation mode: single-sided lines with sound zone boundary flag are now highlightable and clickable.

Fixed, Wavefront .obj Export: long texture names were handled incorrectly causing exceptions during textures export.

Fixed, Linedefs mode, since r2346: some event lines were not redrawn when updating insert vertex preview. 

Classic modes: changed the way event lines are rendered. Should work much faster now. Event lines are now displayed while panning the view.

Fixed, Visual mode, "Auto-align textures" actions: auto alignment was applied incorrectly to middle parts of doublesided lines.
Fixed, Visual mode, "Auto-align textures" actions: in some cases generated texture offsets were not rounded to map format decimal number precision.

Edit Selection mode, UDMF: added "High precision positioning" setting. When enabled, thing and vertex positions will be set using floating point precision. Otherwise, they will be rounded to the nearest integer.

Fixed, Edit Selection mode: floor/ceiling textures rotation was not converted from radians to degrees when "Transform Texture Rotation" setting was disabled.

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

Fixed, Visual mode, UDMF: in some cases texture offsets were changed incorrectly while dragging sidedefs with negative texture scale.

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, Visual mode: z position of info lines for polyobject setup things was calculated incorrectly.
Updated ZDoom_DECORATE.cfg.

Added, Edit Selection mode, UDMF: textures offset, rotation and scale an now be updated while using the mode.
Documentation: updated "DECORATE keys" page.

DECORATE: added "//$ArgNDefault" special comment. It can be used to specify the default argument value.
Visual mode, 3d floors: sloped 3d floors are now always rendered as opaque (just like in GZDoom).
Fixed a crash when creating a new unknown thing (introduced in r2324).
Documentation: updated "Action Argument Settings" and "DECORATE keys" pages.

Game Configurations: added "Thing Radius" (23) and "Thing Height" (24) action argument types. When non-zero, arguments of these types will affect the size of associated thing in Classic and Visual modes.
Game Configurations: updated things in ZDoom "Bridges" category to use argument types 23 and 24.
Documentation: added "Action Argument Settings" page, updated "Basic Settings", "Map Format Settings", "Linedefs Settings" and "Things Settings" pages in Configurations -> Game Configurations group.
Documentation: updated "DECORATE keys" page.

Fixed(?), PK3: SharpCompress doesn't like it when several threads try to read PK3 archive entries at the same time.
Fixed, Visual mode, 3d floors: floor and ceiling alpha calculation was broken.

Updated ZDoom_ACS.cfg and ZDoom_DECORATE.cfg.

Fixed, "Flip Linedefs" action: in some cases my sector based flipping logic was behaving incorrectly.

Added: thing and linedef action arguments can now have tooltips defined in both Game Configuration (using "tooltip" action argument definition property) and DECORATE (using "$argNtooltip" special comment).
Removed "Sectors Brightness Mode" action, because the mode itself was removed long ago...
Documentation: updated "DECORATE keys", "Things Settings" and "Linedefs Settings" pages.