Re: glReadPixels with null pointer

"Mike C. Fletcher" <[email protected]> Wed, 04 Sep 2013 16:46:14 -0400
Newsgroups gmane.comp.python.opengl.devel
Message-ID <[email protected]>
On 13-09-02 01:59 PM, Tim Sheerman-Chase wrote:
> Hi all,
>
> I had problems when using glReadPixels when the data buffer pointer
> passed to the function is zero:
>
> glReadPixels(0, 0, capSize[0], capSize[1], GL_BGRA, GL_UNSIGNED_BYTE, 0)

Hi Tim,

I've merged your patch into bzr head, though with some modifications, as 
"if array != 0:" will trigger "cannot determine the scalar value of an 
array" errors when array is a numpy array (it creates a boolean array of 
size of array then attempts to determine whether array is True/False and 
blows up).

With the modified code *any* integer/long passed in will be converted to 
a ctypes.c_void_p( value ).  I believe that should be fine for all 
normal use cases of the function.

HTH,
Mike

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


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