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powerpad
07-27-2005, 06:52 AM
I have some point p and a plane. Is it possible to defined a matrix like glFrustum with p in the center and the plane be the projection plane?

Do I need to specify near and far always or can near be far since near = 0 is not allowed

memfr0b
07-29-2005, 06:44 AM
Originally posted by powerpad:
I have some point p and a plane. Is it possible to defined a matrix like glFrustum with p in the center and the plane be the projection plane?You can use gluLookAt to align your view frustum with your projection plane normal and center point.


Do I need to specify near and far always or can near be far since near = 0 is not allowedOpenGL does not work by projecting vertices onto a plane, but by transforming them into a unit cube and then dropping the depth component. You still have to specify valid zNear and zFar values for this transformation to work.