These are currently the new shader commands implemented in the updated OA3 renderer (code/renderer_oa) on Github. Not supported in current official binaries (0.8.8).
List is subject to changes.
deformVertex wavenormal Edit
Like deformVertex wave, it has a wave. Like deformVertex normal, it shifts the normals. To be used in conjuction with environmentWater stages for a convincing reflecting water pool effect.
rgbGen flatAmbient Edit
lightingDiffuse without normals and without direct light color (ambient color only). Intended to be used with celshading so you don't have to live with a fullbright model nor goraud shading.
rgbGen flatDirect Edit
lightingDiffuse without normals. This gives the model a flat lighting color. Intended for use with eyeballs and celshading.
rgbGen lightingDiffuseSpecular Edit
Deprecated! This is lightingDiffuse with a touch of specular lighitng added to the calculation. Unfortunately this kept breaking, looking wrong, and was overall slower.
rgbGen lightingDynamic Edit
Obsolete. This is what flatDirect was.
rgbGen lightingUniform Edit
Obsolete. This is what flatAmbient was.
rgbGen vertexLighting Edit
This is intended to be rgbGen lightingDiffuse applied on top of rgbGen vertex. Unfinished and untested.
tcGen environmentWater Edit
Like tcGen environment but with a slightly different projection. It's used to make better, less mirroring psuedo-reflections on floors and ceilings is most effective with water (hence the name)
tcGen cel Edit
Adapted from ZEQ2. Obsolete-ish. It's intended for lighting stages. It works best if the texture is a rectangular gradient.
tcGen celshading Edit
Not related to cel, this is an environment map that reflects from light positions in the world. Not obsolete, but not really used for celshading either. May be renamed (environmentLight?)
This is useful for weapons and other metallic objects to add shine and glimmer to them.
tcGen eyeleft Edit
Used for player models' heads eye surfaces. This projects the texture pointing towards a vector from a fixed vector. In layman's terms it makes the eye look.
tcGen eyeright Edit
Same thing, but using the other eye's vector.