> Date: Wed, 18 Sep 2002 10:38:31 -0400 > From: Lan Wu-Cavener <[EMAIL PROTECTED]> > > I have not seen any response to this note yet. I figured that I may have > not stated the question clearly. I used the ViewFrustum class from j3d.org > to calculate the view frustum for each frame. The depth of the view frustum > I got does not match the distance between the front and back clip distance.
Your description of the definition of the view frustum is correct (at least from the point of the view of the view platform). I'd guess you're having a problem with the difference between physical and virtual coordinates. Java 3D has the unfortunate default of using physical coordinates to define the front and back clip distances. Physical coordinates are how things in the physical world are measured, such as the width of your screen in meters. However, entities in the virtual world are expressed in virtual units, and the view frustum as computed by the j3d.org ViewFrustum class is most likely one of those. The easiest way to get around this is to use the VIRTUAL_EYE front and back clip policies -- that ensures that the clip plane distances you specify are measured from the eyepoint in virtual coordinates. -- Mark Hood =========================================================================== To unsubscribe, send email to [EMAIL PROTECTED] and include in the body of the message "signoff JAVA3D-INTEREST". For general help, send email to [EMAIL PROTECTED] and include in the body of the message "help".
