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05-14-2001, 05:24 AM
Hi..

I am new one in the world of opengl, and have a problem that needs urgent sollution http://www.opengl.org/discussion_boards/ubb/smile.gif.

My question concerns translating and rotating the display lists. I've created a list (1), and I openned one GLX window to render it. I did menage to see rendered display list in that window. But, I cannot move it. I used standard "gltranslatef" and "glrotatef" commands. I cannot see the process of moving, but just the final result. And one thing more. I have the trail, that means that GL draws the display list whenever I call it with "glcalllist". Is there any chance to avoid these problems? How can I manage the speed of moving the diplay lists? Can I work with display list without calling them again and again? Actually, I have simple model that is represented with a couple of independent display list. I have to move some of them in order to simulate the simple procces. Can you give me some simple example, or some internet address for solving this problem?

Thanks...
Couch

Boresight
05-14-2001, 05:35 AM
Exactly as you describe, the display list work. If you rotate or translate into the display list only the final result is viewed.
The display list store only a set of vertexs (probably triangles, I guess) after apply all transformations.

But you can make transformation call glRotate* or glTranslate* before glCallList. You use list for performance, not for flexibility

[This message has been edited by Boresight (edited 05-14-2001).]

Korval
05-14-2001, 11:38 AM
Remember, OpenGL doesn't deal with animations, only the current frame. If you want to see the object actually move to another point in a given amount of time, you will have to make it do so yourself by incrementally translating and rotating it in each frame.

05-14-2001, 02:19 PM
Thanks for comments...
But, can you give me a couple of lines of the simplest code for doing some elementar moving... rotating or translating?

Thanks
Couch