View Full Version : writing to buffer WITHOUT writing to screen

09-30-2000, 04:04 PM
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? http://www.opengl.org/discussion_boards/ubb/smile.gif

09-30-2000, 05:39 PM
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....

09-30-2000, 05:56 PM
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.

Kilam Malik
10-01-2000, 09:01 AM
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.

10-01-2000, 02:08 PM
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)