Other features:

Perhaps each shader/ffp at level geometry, terrain and model last one with move, turn and animation) inside and outside.

Plants with some of that shaders, if possible. I would like to have ffp env_mapping on one of Loopix plants.

Critiques:

The bump mapping has awfully dark 'shadows', and the highlights of the others are a bit too light.

Input:

In HL2 they seemed to relate the ffp env_mapping to the shadowmap, so that you mainly see it in the shadowy part of the levelgeometry.

If you find a way to fix the parallax mapping that it is correct at every surface angle and view angle, that would be great, although I fear that it is tough.

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Perhaps the best way is to start with a basic demo, that can get more and more additions with the help of the community here.

What about collaboration with Rigoletto, maybe he would add an ingame tutorial about how one can modify an ffp or shader!

If one can help out with textures models, level, geometry - just tell us!

This are just suggestions! Thanks for your efforts!