How does opengl-es 2 assemble primitives?

Posted by stephelton on Game Development See other posts from Game Development or by stephelton
Published on 2011-06-29T23:17:04Z Indexed on 2011/06/30 0:31 UTC
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glsl

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opengl-es2

Two things I'm quite confused about.

1) OpenGL ES 2.0 creates primitives before the vertex shader is invoked. Why, then, does it not automatically provide the vertex shader the position of the vertex?

2) OpenGL ES 2.0 supports glDrawElements(), but it does not support glEnableClientState() or GL_VERTEX_ARRAY, so how can this call possibly be used to construct primitives?

NOTE: this is OpenGL ES 2.0, NOT normal OpenGL!

Thanks!

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