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Malchivus

OpenGL what is the Vertex Array prototype on Win32 under SDL

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Malchivus    100
Here goes ... The Microsoft Visual c++ 6.0 Docs say that the OpenGL vertex array functions have a 'count' parameter, i.e: void glVertexPointer( GLint size, GLenum type, GLsizei stride, GLsizei count, const GLvoid *pointer ); The OpenGL programming guide lists it as: void glVertexPointer( GLint size, GLenum type, GLsizei stride, <sans count> const GLvoid *pointer ); But the extension registry says the vertex array extension function is: void glVertexPointerEXT( GLint size, GLenum type, GLsizei stride, GLsizei count, const GLvoid *pointer ); So what I seem to see is two diffrent prototypes for "glVertexPointer." I want to use the SDL_GL_GetFunc() function to retrieve my function pointers, but if it is working on Windows ... how do I know which prototype I should use? I know someone will probaly point out that the ARB should be considered the definitive source for this information, but the Windows implementation is provided by Microsoft not the ARB ... or is this just a typo in the otherwise useful documentation?

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Enrico    316
You don't need to retrieve the pointers for core functions (and glVertexPointer() is definitely a core function). They are defined in <GL/GL.h>, so just include that.

If you still want to important that pointer, the definition from VS6 is correct.

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Brother Bob    10344
The correct prototype for glVertexPointer is without count parameter, and the correct prorotype for glVertexPointerEXT is with count parameter. The documentation for VS6 is wrong on that point.

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Malchivus    100
Quote:
Original post by Enrico
You don't need to retrieve the pointers ...


I know that it is unusual, but SDL needs it if you want to load a diffrent OpenGL library. I should have said that though ... sorry.

Quote:
Original post by Brother Bob
... glVertexPointer is without count parameter .... glVertexPointerEXT is with count parameter...


Ok, so passing "glVertexPointer" will get me one without a count, and "glVertexPointerEXT" will get me one with a count. It sounds counter intuitive - that the extension prototype is more developed - but it seems just as possible.

Thank you both.

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Brother Bob    10344
More parameters doesn't necessarily mean a more developed. There was obviously a reason why they removed it when promoting it to the core. What it was, I don't know, but maybe there just wasn't any real need for it at that time?

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