Formats/Known regressions since Tremulous

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As a mapper or someone creating assets for the game, you may be aware of those pitfalls that can be considered as regressions when comparing with Tremulous or Quake Ⅲ.

See also the Limitations that are not regressions page for things that are not regressions.

Regressions that may make the game look broken

Missing portal blending

Portal blending is not implemented yet in the renderer.

What happens is that the renderer that was used in Quake Ⅲ and Tremulous were OpenGL 1 renderers, and the Dæmon engine renderer is an OpenGL 3+ renderer. The difference between OpenGL 1 and OpenGL 3+ is similar to the difference between OpenGL 4.6 and Vulkan. Those renderers are different software. Everything from the OpenGL 1 renderer had to be re-implemented in OpenGL 3+ renderer with new code.

So the lack of portable blending is not technically a regression as the code never existed in the renderer to begin with. It also means there is no bug in our code.

Though, we fully agree this means a map ported from Tremulous that was using that feature will look broken and that then can be considered as a regression from a player or mapper point of view.

From the code point of view, this is a feature request and we need someone to implement it. We are looking for renderer developers and OpenGL 3+ specialist to implement the feature in our engine.

Missing RoQ video

RoQ video support was removed long time ago as Unvanquished did not make use of it.

Later the last remaining video format was removed, it was a format from an alternate reality that never happened : OGM with Vorbis and Theora. OGM with Vorbis and Theora is not OGG with Vorbis and Theora. The OGM format was a hack purposed for DivX piracy scene to mux XviD video with Vorbis audio, and while OGM with XviD was pretty popular, no one known tool can produce OGM with Vorbis and Theora. illwieckz tried a bunch of current and old software from the era and none was able to produce OGM with Theora and Vorbis. Neither oggenc from vorbis-tools, neither ogmtools, neither ffmpeg (recent and old), neither mencoder, neither OggMux, neither OGMMuxer, neither VirtualDubMod (modded VirtualDub for OGM support), neither ffdshow with OGM, Theora and Vorbis codecs. The only remaining thing untested is some obscure Visual Studio plugin that was mentioned in some places but for which no one file was found yet. We know something existed since Smokin' Guns game uses such OGM with Theora and Vorbis title video. That's all.

Once that cursed OGM with Theora and Vorbis format was removed, the Theora codec was dead code and the Video support was dead code. This dead code was removed at some point because of being dead code.

The removal of Video playing feature and the removal of RoQ support without alternative was controversial, and Dæmon 0.54 will bring back videoMap support with RoQ format.

Regressions that may make the game look broken, but with workaround

Stereo sound effect not being positional

Currently only mono sound files are played properly as positional audio, stereo sound files are played in your face. We need to fix this.

A simple workaround can be applied when repackaging the files: just convert the positional stereo sound as mono, this would make no difference to the player (stereo positional sound is meaningless anyway).

Regressions that don't make the game look broken

Missing alphaGen lightingSpecular

The alphaGen lightingSpecular was a subtle effect applied on some textures. This feature being missing doesn't break the rendering of the texture and if you look at the surface you may not notice something is wrong, unless you do comparative screenshots with Tremulous and Unvanquished.

Implementing this feature has very low priority as there is no impact on gameplay and textures don't look bad without it. The game don't look broken without it and one cannot know the feature is missing just by playing the game, unless some warning tells it in log.