Re: [PyOpenGL-Users] Problems with glReadPixels

[Mike C. F. <mcf...@vr...>]

Dirk Reiners wrote:
> 	Hi everybody,
>
> we're trying to use glReadPixels with PyOpenGL, but we're running into exceptions:
>
> Traceback (most recent call last):
> File "/store/home/mukaissi/MetNetVis/MetNetVis/UI/graphdrawwidget.py",
> line 155, in mousePressEvent
>
> index=GL.glReadPixels(event.x,event.y,1,1,GL.GL_RGB,GL.GL_UNSIGNED_BYTE)
> File
> "/store/home/mukaissi/software/PyOpenGL-3.0.0a6/OpenGL/GL/images.py", line
> 279, in glReadPixels
> ctypes.c_void_p( arrayType.dataPointer(array))
> ctypes.ArgumentError: argument 1: <type 'exceptions.TypeError'>: wrong
> type
>   
...
> This is using 3.0.0a6 on an x86_64 (RHEL) system.
>
> Is anybody using glReadPixels successfully? What are we missing?
>   
I don't have any code that uses the un-decorated version.  
glReadPixelsub seems to work fine (at least, the 
OpenGLContext/tests/saveimage.py test works fine on my CVS-based version 
of PyOpenGL).  That's on an AMD64 Gentoo machine.  Code looks identical 
for the two versions of the function (other than a type being specified 
by default).

If you have failing code I could pdb through it might be easier to track 
down the issue.  One other thing, what versions of ctypes and numpy are 
you using?

Good luck,
Mike

-- 
________________________________________________
  Mike C. Fletcher
  Designer, VR Plumber, Coder
  http://www.vrplumber.com
  http://blog.vrplumber.com