Polygone Crossing

Why do I have THIS http://www.kuenzle-family.ch/philippe/error.jpg
when two object are overlapping using a GForce2 MX and I don’t when I am using a GForce3…
Also, I saw some demo running open GL on my GForce2 MX not having this problem. The “sea” was one huge polygone and “mountain” was coming out of those and the border between mountain and sea wasn’t doing that mess…

Thanks

Your depth buffer precision is too low. Either increase your zNear or decrease your zFar, or do both. You are probably setting these variables with a call to gluPerspective somewhere in your initialization code. zNear and zFar are the last 2 parameters.

As a side note, this question has been asked many times before. This problem and many others that get asked quite often are in the OpenGL FAQ, which you can find at http://www.opengl.org/developers/faqs/technical.html

j

Thank you very much.
I have to say that I looked through those, but it is not easy to find what you are looking for when you don’t know what it is called and what is creating a problem

i have the exact same problem and the same 24 bit depth buffers activated on a geforce 2 and a geforce 3 result in the gf3 not having these artifacts and the geforce 2 having them. of course, minimizing view depth solves this problem, but why can this happen if the precision bit’s are actually same on both cards??? some one have an idea on that one? from my understanding this should not happen.

regards,
chris

Originally posted by j:
[b]Your depth buffer precision is too low. Either increase your zNear or decrease your zFar, or do both. You are probably setting these variables with a call to gluPerspective somewhere in your initialization code. zNear and zFar are the last 2 parameters.

As a side note, this question has been asked many times before. This problem and many others that get asked quite often are in the OpenGL FAQ, which you can find at http://www.opengl.org/developers/faqs/technical.html

j[/b]