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Stan
06-05-2002, 07:50 PM
I'm drawing an imitation of disco ball by calling glClear only once for several turns of the display function. It turns out pretty cool. However, when I need to combine it will other drawing that do need glClear all the time, I get stuck.
Is there anyway I can combine the two successfully or is it simply impossible?

P.S. Anyone have suggestion of how to draw an imitation of disco ball that is quick and easy? No need to be very realistic.

dorbie
06-06-2002, 07:23 AM
Use texgen on a spheremap (or cubemap) and a piece of faceted geometry to create a mirror effect. Optionally apply a second texture to modulate the first so that there are non reflecting gaps between facets.

[This message has been edited by dorbie (edited 06-06-2002).]

Stan
06-06-2002, 12:18 PM
Thanks. I'm VERY new to OpenGL, thus I don't really know what are the things you mentioned. Could you or anybody else answer my question about glClear though?

zeckensack
06-06-2002, 06:17 PM
Originally posted by Stan:
Thanks. I'm VERY new to OpenGL, thus I don't really know what are the things you mentioned. Could you or anybody else answer my question about glClear though?Hmm, could you rephrase your question again? All I understood so far is that you draw something by not clearing buffers. Never worked for me http://www.opengl.org/discussion_boards/ubb/wink.gif

More details please http://www.opengl.org/discussion_boards/ubb/smile.gif

Mazy
06-06-2002, 10:06 PM
Sorry, you cant do that in a easy way, the next best think would be to draw the discoball in a pBuffer and use it as a texture billboarded) on the screen every frame, then you dont need to clear the pbuffer every frame, but the normal framebuffer could be cleared