   Problem in Perspective projection
  Being successful in rendering 3D walls in Orthographic projection, I simply tried to change the Projection to Perspective which gave some wierd rendering. The Walls could be seen properly, but some strips/bands appeared on the wall surface. As I rotated the wall, the bands were found to change their positions and sizes.The only thing I changed was as follows:gluPerspective(60f, (double)this.Width /(double) this.Height, 0.001, 100.0f);glTranslatef(-3f, -2f, -20f);Could someone please help me out?   
  Could you post a screenshot showing the 'stripes'?I'm unsure what you mean by stripes. It could be aliasing. But a screenshot would make it easier to solve your problem.   ;  Can it be a Z-buffer precision problem ? Do your walls have the "two sides" very close ?;  It may be a problem of Z-precision, because the stripes which I talk about, have the color of the backside of the wall. So, I am sure that this is a z-precision problem. But the question is that why does this issues arise only for Perspective projection? And what do we do to repair it?   ;  Where are your walls positioned in relation to the front and back clipping planes of the view frustum? Have you considered the 1/z-relation in the z-buffer?   ;  I am making this sure that the front and back clipping planes do not cut the walls. But what is this 1/z relation in the z-buffer? And isn't it required for Orthogonal projection?   ;  Hi All,I am uploading the snap of my Perspective View against the Orthogonal View. Please have a look. Dybbuk, what you say seems to be right. I too feel that aliasing is causing a problem.The link for the snap is:http://www.geocities.com/vivekdharm/perspective_vs_orthogonal.jpgAlso note that edges of the wall are not clearly visible in the Perspective view.   ;  Increase zNear a bit, try 1.0.   ;  You seem to be a very good friend of mine Kalidor. This is for the second time I receive a perfect solution from you and my forum thread ends up with a gratitude mail for you. Thanks again.   ;Quote:Original post by vivekdYou seem to be a very good friend of mine Kalidor. This is for the second time I receive a perfect solution from you and my forum thread ends up with a gratitude mail for you. Thanks again.Hah, it's my pleasure. [smile]For a good introduction to how the depth buffer works, go here.  The server seems to be down right now so try it again later.  Or google for "Learning to Love Your Z-buffer" because it's probably hosted somewhere else as well.   