Changes from 3.1.0:
Merged with QZDoom 2.0.0
"Software" light mode (in OpenGL) now supports radial fog setting
Unsloped Flats can now use non-power-2 textures in software mode
Menus now merge in with a mod's custom MENUDEF when it provides menu replacements. This is due to older mods' menus becoming very quickly outdated.
Rise of the Wool Ball is now supported as an IWAD
Custom IWAD support is now available. A custom IWAD file must have the extension ipk3/iwad, and contain a "iwadinfo" lump similar to GZDoom.pk3's with only this IWAD's information and no file list.
"Classic Transparency" option - turn off ZDoom's additive transparency effects for the original game resources.
Better non-accelerated buffer support for software rendering - when vid_hw2d is disabled or otherwise using an unaccelerated framebuffer, stencils and on-screen objects now show up better.
(Windows only) vid_used3d is now renamed to vid_glswfb. This matches the same CVAR that is available on Mac/Linux.
vid_glswfb is now exposed to the menu.
r_visibility now affects GL's Software lightmode as well as Softpoly.
Player Sprite overlays now support the PSPF_MIRROR flag which flips the sprite horizontally across the entire screen.
Menu Blurring option - when running in OpenGL mode, a mod can now blur the screen when the menu is active.
Unfriendly players - when a PlayerPawn object has -FRIENDLY set, they become a playable monster and interact with the game world as one. Additionally, they become deathmatch opponents, capable of dealing and taking damage from other players.
Custom Screen Shaders - mods are now able to include their own post processing shaders, insertable before the bloom pass ("beforebloom"), before 2D objects are drawn ("scene"), and after everything is on the screen ("screen").
vid_saturation saturates/desaturates the screen - improves the appearance of the screen when using certain brightness/gamma settings as well as allowing the user to play in 'black and white' (similar to the display control panel option). (Requires post-processing shaders to be active and hardware gamma must be disabled)