Re: [PyOpenGL-Users] glGenVertexArrays producing 'invalid enumerant' error.

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

On 11-10-12 03:34 AM, tolomea wrote:
> Version stuff:
> Python 2.7.1+ (r271:86832, Apr 11 2011, 18:05:24) 
> [GCC 4.5.2] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
> import OpenGL
> OpenGL.__version__
> '3.0.2a1'
> I'm using FORWARD_COMPATIBLE_ONLY, context version 3.3 and GLUT_CORE_PROFILE.
>
>
> I'm porting a working (same machine and environment etc) C program to Python, 
> and the glGenVertexArrays function is giving me grief.
>
> The pythonic form:
>     vao = glGenVertexArrays(1)
> produces "TypeError: this function takes at least 2 arguments" which I presume 
> means it hasn't been wrapped yet.
Yes.
> I've no idea what could be causing that and googling hasn't turned up anything 
> useful.
>
> Does anyone have any suggestions as to where to look?
> Are there any known working examples of using vertex array objects and pyopengl 
> that I could cross check against?
My go-to guess with almost any Python-differs-from-C problems during
init is to look at the error-checking code.  PyOpenGL's biggest
difference from C code is that it runs error checking after every call. 
I'm guessing either your context isn't quite ready-to-go and you're
getting an error from the error checking, or that the line before had an
error and the error checking picked it up a line late.

import OpenGL
OpenGL.USE_ACCELERATE = False
OpenGL.ERROR_CHECKING = False

at the top of your script should let you quickly determine a) where the
problem is b) whether the problem is with error checking.

HTH,
Mike

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