pyopengl-users

[PyOpenGL-Users] glRectfv ctypes bug?

[altern <al...@gm...>]

hi

I am porting an old app to the new PyOPenGL and I get an error at

glRectfv( vlist[0], vlist[2] )

It says

"wrappercall types.Argument.Error: ("argument 1: <type 
'exceptions.TypeError'>: byref() argument must be ctypes instance, not 
'tuple', [(-5.5, -5.5), <OpenGL.arrays.listsc_floatArray_2 object at 
0x02x10210>])"

my bet is that this is a bug because I can replace it by

glBegin(GL_QUADS)
glVertex2fv( vlist[0] )
glVertex2fv( vlist[1] )
glVertex2fv( vlist[2] )
glVertex2fv( vlist[3] )
glEnd()

and this draws the rect with no errors at all.

enrike

Re: [PyOpenGL-Users] glRectfv ctypes bug?

[altern <al...@gm...>]

sorry, this was on windows XP with python 2.5 and pyopengl3.0.0a6-py2.5.egg

altern(e)k dio:
> hi
> 
> I am porting an old app to the new PyOPenGL and I get an error at
> 
> glRectfv( vlist[0], vlist[2] )
> 
> It says
> 
> "wrappercall types.Argument.Error: ("argument 1: <type 
> 'exceptions.TypeError'>: byref() argument must be ctypes instance, not 
> 'tuple', [(-5.5, -5.5), <OpenGL.arrays.listsc_floatArray_2 object at 
> 0x02x10210>])"
> 
> my bet is that this is a bug because I can replace it by
> 
> glBegin(GL_QUADS)
> glVertex2fv( vlist[0] )
> glVertex2fv( vlist[1] )
> glVertex2fv( vlist[2] )
> glVertex2fv( vlist[3] )
> glEnd()
> 
> and this draws the rect with no errors at all.
> 
> enrike
> 

Re: [PyOpenGL-Users] glRectfv ctypes bug?

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

altern wrote:
> sorry, this was on windows XP with python 2.5 and pyopengl3.0.0a6-py2.5.egg
>
> altern(e)k dio:
>   
>> hi
>>
>> I am porting an old app to the new PyOPenGL and I get an error at
>>
>> glRectfv( vlist[0], vlist[2] )
>>
>> It says
>>
>> "wrappercall types.Argument.Error: ("argument 1: <type 
>> 'exceptions.TypeError'>: byref() argument must be ctypes instance, not 
>> 'tuple', [(-5.5, -5.5), <OpenGL.arrays.listsc_floatArray_2 object at 
>> 0x02x10210>])"
>>     
Neat, it was a pretty stupid little bug. I wrapped the function with a
type annotation for the first argument and then immediately threw away
that annotated function when I wrapped the base function again to
annotate the second argument. That said, I wasn't able to reproduce the
precise error (though I got lots of other wonky errors with glRectf as a
result of the problem).

Hopefully that will take care of your issue too,
Mike

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