PyOpenGL glVertexPointer trouble

[Mike C. Fletcher]

TheDustbustr wrote:
...

>I want to port this to glVertexPointer code.  Here is what I have so far:
>  
>
...

>        glVertexPointer(3, GL_FLOAT, 0, VertexArray)
>  
>
...

>This doesn't work... What am I doing wrong?  I have tried variations to this
>code, end results have been PyGame "parachuting", PyGame segfaulting, or
>nothing being displayed at all.  The glVertex3f code works exactly as expected.
>  
>
Looks like there's something weird going on with the glVertexPointer 
code.  I can imagine that almost no-one has used the raw glVertexPointer 
function, given the alternate spellings being so much easier to use from 
Python.   The segfaulting etceteras is possible because the undecorated 
method is basically letting you specify directly to the OpenGL engine a 
set of array-traversal specs. If you get them slightly off (e.g. length 
 > array) you'll potentially get a memory-access failure.  That, and the 
ease of using the decorated functions is probably why no-one has 
stumbled across the error before.

I've added a bug report to the PyOpenGL project assigned to me, will try 
to get to it fairly soon.

Here's a working version of your code that uses the "decorated" 
function, in case you want it:

points = array([[0,0,0],[1,0,0],[1,1,0],[0,1,0]], 'f')
indices = array( range(len(points)), 'i')

class TestContext( BaseContext ):
    def OnInit( self ):
        """Initialisation"""
        print """Should see square over black background"""
    def Render( self, mode = 0):
        BaseContext.Render( self, mode )
##        glVertexPointer( len(points),GL_FLOAT, 0, points)
        glVertexPointerf( points )
        glEnableClientState(GL_VERTEX_ARRAY);
        glDrawElementsui(
            GL_QUADS,
            indices
        )

Enjoy,
Mike

_______________________________________
  Mike C. Fletcher
  Designer, VR Plumber, Coder
  http://members.rogers.com/mcfletch/