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From: Lawrence D'Oliveiro <ldo@nz.invalid>
Newsgroups: comp.lang.python
Subject: Python OpenGL The Proper Way (Posting On Python-List Prohibited)
Date: Thu, 26 Sep 2024 05:42:44 -0000 (UTC)
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Funny thing: the OpenGL specs document all routines and constants
*without* “gl” and “GL_” prefixes. It makes sense to add these in a
language that does not have namespaces, like C. In Python, it does
not. So this routine takes apart the contents of the PyOpenGL modules
into separate pieces, with those unnecessary prefixes stripped. So
instead of calling OpenGL.GL.glClear(), say, you can call gl.Clear().
And instead of referring to OpenGL.GL.GL_ACCUM, you can use GL.ACCUM
instead. Much more concise all round.

    import types
    import OpenGL
    import OpenGL.GL
    import OpenGL.GLU

    def gen_gl() :
        "generates versions of the PyOpenGL modules without spurious prefixes on names."
        gl = types.ModuleType("gl", doc = "OpenGL routines")
        GL = types.ModuleType("GL", doc = "OpenGL constants")
        glu = types.ModuleType("glu", doc = "OpenGL utility routines")
        GLU = types.ModuleType("GLU", doc = "OpenGL utility constants")
        for prefix, src, dest in \
            (
                ("gl", OpenGL.GL, gl),
                ("GL_", OpenGL.GL, GL),
                ("glu", OpenGL.GLU, glu),
                ("GLU_", OpenGL.GLU, GLU),
            ) \
        :
            for name in dir(src) :
                if name.startswith(prefix) :
                    setattr(dest, name[len(prefix):], getattr(src, name))
                #end if
            #end for
        #end for
        return \
            gl, GL, glu, GLU
    #end gen_gl
    gl, GL, glu, GLU = gen_gl()

Now you can write code like

    gl.Clear(GL.COLOR_BUFFER_BIT | GL.DEPTH_BUFFER_BIT)
    gl.MatrixMode(GL.PROJECTION)
    gl.LoadIdentity()
    gl.Ortho(0, 640, 0, 480, 0, 1)
    gl.Color3f(0, 0.5, 0.5)
    gl.Begin(GL.QUADS)
    for v in \
        (
            (100, 100),
            (100, 200),
            (200, 200),
            (200, 100),
        ) \
    :
        gl.Vertex2f(*v)
    #end for
    gl.End()

etc. Much cleaner, don’t you think?