bumps in fixed function shader

Discussion in 'ShaderLab' started by pitibonom, Apr 24, 2013.

  1. pitibonom

    pitibonom

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    Hi all !

    I'm wondering wether it's possible or not to have bumpmaps in fixed function shader ?
    The doc didn't help me very much ( thouth the 'material' keyword might be one possibility ) and the
    awesomely crappy search engine in this forum got me thousands of useless posts...

    Mebe someone already wrote such a simple and fast shader ?
    I'd be please to get more info about this ;)

    thanks for your answers and help !

    regards.
  2. tomvds

    tomvds

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    Bump mapping requires pixel shading, which is not possible in the fixed function pipeline. If you want bump-mapping, you will have to use a Cg shader.
  3. Jessy

    Jessy

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    That's not true; you can do object space normal mapping using the undocumented Dot3 texture combiner.

    http://forum.unity3d.com/threads/14797-colored-speculars-and-bump-map

    That said, there's no reason to use a fixed function shader anymore. I write in GLSL first, so I can get a performance prediction from PVRShaderEditor, and then copy it to Cg if I need to support a blah platform.
  4. pitibonom

    pitibonom

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    Hi !

    Thanks for this accurate answer Jessy !
    Yes i remember in the prehistoric times when the 3Dfx ruled the world, a guy from this company
    found a way to do realtime bump mapping. In this times those boards ( the Voodoo2 ) had nothing but fixed function
    shaders.

    the small fixed func shader:
    works in an interresting way. Now that i know the key is on the combine fixed function i gonna dig this way.

    thanks a lot and have a nice day !
    Last edited: Sep 20, 2013