writing to buffer WITHOUT writing to screen

So, I want to process a batch of files, outputting a bitmap. I’ve got the rendering and the bitmap part done. But I’d like to do it without ever writing to the monitor, and ideally without even having X running concurrently (I’m running Linux). Some ideas were floated in this disussion board a few weeks ago, but no resolution was reached. Any new ideas? (if you use glutHideWindow, it just never draws to the buffer…)

Any suggestions?

So what you are saying is that you can’t get a backbuffer up and running to make things easier?

Sorry if my X and *nix knowledge is very limited…

It’s more complicated than that. I think I might have found a non-portable way to do it- it looks like Mesa (the OpenGL clone for Linux that I’m using) has some special functions for off-screen buffers. I haven’t had a chance to code it yet, though. No GLUT way that I can find, unless somebody else has suggestions.

I’m not very much into UNIX and glut, but in windows you can render into a bitmap by specifying a bitmap as your render context rather than a window. Maybe there are similar functions in glut. With mesa I know it’s possible.

See my post in the Linux discussion forum
for code that draws to a .bmp without opening
a window.

It does require X to be running though
(but not necessarily on the local machine…
mmm… networking)