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pythonopenglpyopenglvertex-buffer

How to specify buffer offset with PyOpenGL

What is the PyOpenGL equivalent of

#define BUFFER_OFFSET(i) (reinterpret_cast<void*>(i))

glDrawElements(GL_TRIANGLE_STRIP, count, GL_UNSIGNED_SHORT, BUFFER_OFFSET(offset))

If the offset is 0, then 

glDrawElements(GL_TRIANGLE_STRIP, count, GL_UNSIGNED_SHORT, None)

works, but I can not figure out how to specify a non-zero offset into a buffer object.

Solution

  • You're supposed to pass a ctypes void pointer, which can constructed by :

    ctypes.c_void_p(offset)

    There seems to be a more PyOpenGL specific option using a VBO class, and gotcha with some versions of PyOpenGL according to this.