In #developer-talk, Xenthio explained that his Source 2-style renderer is a replacement for shaderapi plus his own lightmap baker. Baking takes about 40 seconds on a map's first load; after that the map opens instantly.

Badger9 confirmed tex2Dlod returns 0 in vs_3_0 shaders and asked for $vertextexture0 support, for things like deformable snow and water ripples.

Cheatoid posted a snippet crashing x64 with mcore. robotboy655 couldn't reproduce; Cheatoid then concluded it's a race condition.

artemking4 explained on the hardware skinning request that the third weight can be inferred in the vertex shader, so the engine expects at most 2 stored weights. In #next-update he called it "very important" for the shader folks; march noted that means 3 weights work.

In #next-update, Evgeny Akabenko asked Rubat to publish on GitHub the source of GMod's own, non-Valve shaders: g_bloom, g_blurx, g_blury, g_bokehblur, g_colormodify, g_downsample, g_morph, g_premultiplied, g_refract, g_screenspace, g_sharpen, g_sky, g_sobel, g_sunbeams and g_texturize. not.ejay noted they could already be decompiled half decently with vcs-decompiler, but saw no reason not to publish them.

Akabenko wrote on his request to add the 3D skybox to SSAO_DepthPass that a stencil is needed, because the game world is expected to always render on top of the 3D skybox.

In #next-update, Earu asked why fading static props stop writing depth while they fade out. Artemking4 and Evgeny Akabenko explained that fading props are moved to the translucent pass, and translucent objects don't write depth. In the evening discussion, Rubat asked why transparent props would write depth at all, and said alpha testing is irrelevant for fadeouts. Earu said he would remove his issue. Evgeny Akabenko and Earu then discussed dithered fades combined with TAA.

robotboy655 closed Akabenko's PR using string.find to detect cable shaders: it wouldn't be faster and would let non-existent shaders with "cable" in the name through.

a-straight-white-male reported that $seamless_scale breaks the second normal map on WorldVertexTransition materials.

Commit 4e35e7 on main fixes the spawnmenu middle mouse click regression, makes the spawnmenu survive addons that provide incomplete NPC weapon data, and replaces the shipped edited Infected materials with a fallback done in code.

Akabenko asked to stop overwriting the original L4D2 .vmt files and instead set the Infected shader's fallback to VertexLitGeneric. It was closed as completed on 5 October; commit 4e35e7 does the fallback in code.