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1) What to do if part of a shader pair is not present? DISCUSSION: There are several shader types that go together. For example, a VERTEX_SHADER and a FRAGMENT_SHADER form a pair that is part of the geometry pipeline. It is not required to supply both shader types of a pair in a program object. RESOLUTION: If one or the other of a pair is not present in the program object, OpenGL will substitute the standard 1.4 OpenGL pipeline for the one not present.
if someone wants to submit a patch I will roll it in.
mPosShader = gl::GlslProg( shared_ptr<DataSourcePath>(), loadResource("pos.frag"));
Is this normal? It's not very intuitive...