The filenames will be "shader_X.vert" or "shader_X.frag" where X
the shader ID.
<li><b>cache_info</b> - print debug information about shader cache
-<li><b>opt</b> - force compiler optimizations
+<li><b>cache_fb</b> - force cached shaders to be ignored and do a full
+ recompile via the fallback path</li>
<li><b>uniform</b> - print message to stdout when glUniform is called
<li><b>nopvert</b> - force vertex shaders to be a simple shader that just transforms
the vertex position with ftransform() and passes through the color and