For this had to extend WebGLRenderer a bit:
- MeshShaderMaterial now can take non-specific float array uniforms as "fv1"
(there is already "fv" type for array of 3-item-vectors, which probably should be renamed to "fv3" to be consistent)
- render method has yet another parameter "clear" for clearing newly set framebuffer (defaults to true).
This is a bit hackish but it seems necessary to control this somehow. I didn't manage to replicate
desired behavior just with autoClear.
- another dirty thing is accessing GL context from the application side:
renderer.context.disable( renderer.context.DEPTH_TEST );
This should be refactored somehow, wrapped in some API call.
