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OpenGL Z-buffer seems to be drawing backwards....

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Hey all, I'm a newbie to OpenGL, so bear with me here.... I'm making a maze program for my graphics class and I'm running into problems with the Z buffer (I think). All my walls and the ground draw, but it seems that if any polygons are supposed to be drawn "behind" another, the closer one will stop drawing at that point. For example, with closer walls in the maze, I can only see the top of the wall, while the wall behind it fills in the rest of the space. To see the current state of my maze, you can go to http://www.drewan.cc/openGL/maze.exe. Some of you might recognize the maze-creation algorithm from http://www.gamedev.net/reference/articles/article1637.asp (the objective of this program is not to demonstrate the capability to create a maze, but to demonstrate understanding of the camera). For controls, use the arrow keys. Keys 1-9 adjust the camera independently, modifying the 9 glLookAt parameters individually (hold shift to go the other way). If anyone could let me know where I am going wrong with this, I would greatly appreciate it. If all else fails, I'll just remove the floor and turn all the walls a single solid color again, so you can't tell the difference between a close wall and a near wall. =D Edit: Oops, my bad, uploaded the wrong version of the maze....

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a screenshot would be more helpful, usually dont download programs like these from the net. My guess is that you are setting your near and far plane too far apart, try bringing the far plane closer or pushing the near plane back. The ratio between them should be no more than 1000.

HTH

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Sorry, here's a screenshot:

http://www.drewan.cc/openGL/screenshot1.jpg

I'm not sure if GameDev allows image insertion into posts.

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I just tried playing with the near and far planes and that seemed to work. Thanks!

Here's my confusion, though.... The near plane was set to -10, the far to +10, and the scale I use for each "square" of the maze is 100x100. So why is it that when I switched the near plane to +10 and the far plane to -10, it showed up correctly? Is it just me, or does this sound backwards?

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