Re: [Opensg-users] rendering to memory buffer

[Joerg B. <jb...@ot...>]

Dirk Reiners wrote:

>>is it possible to let OpenSG render a scene directly to a buffer in
>>memory? The image grabber foregrounds do glReadPixels but maybe one can 
>>do this without this copy operation.
> 
> if you really want to get into memory, I don't think you can. Given that
> the graphics card can only render into memory on the card, at some point
> you will have to copy it from the card, and glReadPixels is as good a
> way as any.

In my case will glReadPixels do some conversions of the image (like
flipping it vertically, aligning every scan line to word boundaries),
because I want to use it in a Windows GDI bitmap.
I don't believe that these operations are done by the graphics hardware
- at least not on my card. So this is a little bit slow.

What I want is that the scene is directly rendered into the bitmap in
this odd Windows format. Ok, this looks like OpenGL wizardry. :(


Regards, Joerg.