Re: [PyOpenGL-Users] Odd framebuffer error

[Derakon <de...@gm...>]

Thanks for your response, Alejandro. Answers inline.

On Wed, Dec 1, 2010 at 10:11 AM, Alejandro Segovia <as...@gm...> wrote:
> Hi Derakon,
>
>
> These are just a couple of things you might want to check (if you haven't
> already). From the top of my head, I would expect all of these to trigger
> Invalid Operation errors:
> 1) Since "megaTileFramebuffer" is a global variable, are you sure you are
> calling glGenFramebuffers with a valid OpenGL context? If you make the
> assignment at file scope, this is probably running before the context is
> created. This could trigger an Invalid Operation. Also, try printing
> "megaTileFramebuffer" to the console and make sure it's not 0.

I initialize megaTileFramebuffer to None when the module is loaded,
and only call glGenFramebuffers the first time the buffer is required.
Printing it prints "1".

> 2) Has the texture identified by "self.texture" already been created
> (glGenTextures) when attempting to bind the FBO?

Yes; glGenTextures is called in the class's __init__, well before this point.

> 3) Have you tried using GL_FRAMEBUFFER as the first parameter for
> glFrameBufferTexture2D?

I'm not even making it that far; the program stops at the
glBindFramebuffer call. But yes, I've tried GL_FRAMEBUFFER as well as
GL_DRAW_FRAMEBUFFER.

> 4) This might sound silly, but are you certain this is not being executed
> "inside" a glBegin?

To the best of my ability, I am -- the code calling my stuff is rather
messy, but I don't see anything beforehand that would be setting up a
special context.

> Good luck!
> Alejandro.-

Thanks.
-Chris