This release enhances vanilla DOOM render hack support and adds new Doomsday Script bindings.
DOOM render hacks. TNT: Evilution and The Plutonia Experiment use several render/map hacks to take advantage of quirks in the original DOOM renderer. Many of these effects are now supported (or fixed) in Doomsday. Examples: TNT MAP02 deep water, TNT MAP02 windows overlooking the deep water, TNT MAP09 transparent window, TNT MAP31 Arachnotrons inside pillars.
Scripting. Several new Doomsday Script bindings were added, allowing access to game, player, and thing properties. In addition to spawning things, one can now list things by type, check their state and flags, and perform state changes on them. Things can also have an “On death” script that gets run when the thing dies. Bitwise operators are now available in scripts.
Modding. Sprite renaming is supported via DeHackEd. In Heretic, ambient sound sequences can be redefined and new ones can be added via the Audio module. Changing the sequences is also possible during gameplay. The earthquake effect from Hexen is now also available in Heretic. It can be controlled via scripts.
Renderer. Player HUD weapon models may specify a custom FOV value for rendering so that model authors have more control over the appearance, for instance to replicate a 2D sprite appearance more faithfully.