Re: overlay planes

New Message Reply Date view Thread view Subject view Author view

Ed Millard (millard++at++hawkeye.newport.sgi.com)
Tue, 25 Apr 1995 09:45:25 -0800 (PDT)

>
> I am wanting to draw in the overlay planes using OpenGL. Can I use overlay
> planes with OpenGL ? If not, how will the new Performer 2.0 support overlay
> plaens.
>
>
>
Yes, you can use overlays in OpenGL. You get a context in the overlay planes
with glXChooseVisual as described in this excerpt from the man page:

     GLX_LEVEL Must be followed by an integer buffer-level
                           specification. This specification is honored
                           exactly. Buffer level zero corresponds to the
                           default frame buffer of the display. Buffer level
                           one is the first overlay frame buffer, level two
                           the second overlay frame buffer, and so on.
                           Negative buffer levels correspond to underlay frame
                           buffers.

I've also used X11 code written by Mark Kilgard that returns all the visuals
with a transparent pixel and then you can look through these for the deepest
visual avialable in the overlay planes.

=============================================================================
Ed Millard | 18201 Von Karman Avenue
Silicon Graphics Inc. | Suite 100
Developer's Support Group | Irvine, CA 92715
millard++at++sgi.com | (714) 756-5975
=============================================================================

New Message Reply Date view Thread view Subject view Author view

This archive was generated by hypermail 2.0b2 on Mon Aug 10 1998 - 17:51:25 PDT

This message has been cleansed for anti-spam protection. Replace '++at++' in any mail addresses with the '@' symbol.