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arthas
03-31-2008, 07:04 AM
Hi, I wrote a program that simulates radiography, I use 3d texture as volumes,GL_QUADS to map the slices of texture and glfunc(add) to blend the quads. the program works but i see some strange lines, anyone knows which could be the problem? I tryed to draw the quads more closest but I always have the problem.. here is an example(i've highlighted examples of the wrong lines):
http://img370.imageshack.us/img370/3771/errimagenz7.th.jpg (http://img370.imageshack.us/my.php?image=errimagenz7.jpg)

Relic
03-31-2008, 07:49 AM
What's the size and content of the texture compared to the rendering output?
That is, if you have any regular pattern in those texture and you filter linearly into a size which is smaller than the textures you might get any sorts of texture aliasing.
(E.g. filter a checkerboard texture smaller with GL_LINEAR minification and you'll see.)

arthas
03-31-2008, 08:05 AM
the texture is a cube that contains a volume made of smaller cubes. The size should be the same of the texture because I use glViewport,glReadPixels, with the dimensions of the texture.. so what could be? it's like the program don't see some pieces of image and so it reads "holes". the position of GL_QUADS and the frustum should be ok, otherwise I should see the image.. what I have to do? :-(