See related SimGear commit e8ffe461
Now the orthophoto texture coordinates are contained in gl_TexCoord[2],
so no need to pass any custom vertex attributes to Effects that use
photoscenery.
- Remove all Compositor Effects and Shaders.
- Unify the low-spec and ALS pipelines in a single pipeline called 'Classic'.
- Readd shadow mapping.
- Move the WS30 Effect and fragment shader out of the Compositor-specific directories.
Use two-pass rendering for some shaders to reduce the cost of expensive shaders.
Implement some material animations using a shader uniform.
Eliminate use of gl_FrontFacing. It's too buggy on ATI/ Macintosh.
The main problem was using gl_FrontMaterial.ambient with a color mode
of AMBIENT_AND_DIFFUSE i.e., the fixed function path would take both the
ambient colors from the vertex color value. Also, some vertex shaders
were not writing gl_FrontColor even though the fragment shader was
accessing gl_Color.
Author: Tim Moore <timoore@redhat.com>
