Face Problems when Z-Near down!!!

leodeus
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Post: #1
HY again people!!

I have working in this, but the problem persist.
So:

See this : http://labsim.estig.ipb.pt/test1.jpg

In 2, when z-near is down, i dont see the face in a top view... (i can see only the back face if i want), but i want see the front face like in 3.

Any ideias? How force the face to close and can see always the top face?... Is there a problem with the graphic card or with opengl can i force this?...

???
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Luminary
Posts: 5,143
Joined: 2002.04
Post: #2
You have to create a fake face inside the viewing volume if you want to see it.
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leodeus
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Post: #3
Fake face!!!!???? How??
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Luminary
Posts: 5,143
Joined: 2002.04
Post: #4
just make a new quad where you want it (just in front of the near plane).
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leodeus
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Post: #5
Hummm ... ok...
but i want down and down the Z-Near at touch in Z-Far, so that i have make manually many and many quads.... this is not " my" the solution.

Some other ideias?? how to know in there pixeis (case 2 ) I have a face?

Thanks
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Luminary
Posts: 5,143
Joined: 2002.04
Post: #6
you don't have to make many quads, just a different one each time.

In order to find out what kind of "cap" you need to draw, you will have to calculate the intersection of the near plane with your edges to get a new set of vertices, then somehow (perhaps with the GLU tessellator) turn those into triangles.
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