I remember seeing some utility code from Sun for clipping triangles. I just can't seme to find it. Does anyone know where that is?
Dave Yazel ----- Original Message ----- From: "Mauricio Vives" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Monday, July 15, 2002 4:51 PM Subject: Re: [JAVA3D] Model clipping Dave, It would indeed be tricky to use clipping planes to create holes, and it may not actually be possible. As you already noticed, you end up clipping everything if you use standard clipping planes to try to create a hole. Java 3D uses clipping plane support from the underlying graphics API, and that support is limited to half-spaces as Mark described. But I have heard of stranger things. For example, from the SIGGRAPH 99 OpenGL course notes (a gold mine of tips and tricks), we have an explanation of how to use a stencil buffer for constructive solid geometry (booleans): http://www.opengl.org/developers/code/sig99/advanced99/notes/node22.html Not that this helps with Java 3D, but it is interesting to see what is possible with clever tricks! In any case, I think that for your situation (putting holes in terrain geometry for basements), you will either need to generate the hole in advance, or allow your engine to modify the terrain geometry dynamically (i.e. drop a house here, and the engine cuts out the hole for you). There may be a more clever solution out there, but I imagine that almost all games out there which render terrain with holes use one option or the other. - Mauricio -----Original Message----- From: David Yazel [mailto:[EMAIL PROTECTED]] Sent: Monday, July 15, 2002 2:49 PM To: [EMAIL PROTECTED] Subject: Re: [JAVA3D] Model clipping I never got a response on this, so I thought I would resend it. Also, can anyone explain the Vector4d that defines the clipping planes, or does anyone have examples of how this works? Thanks, David Yazel ----- Original Message ----- From: "David Yazel" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Sunday, June 16, 2002 12:44 AM Subject: [JAVA3D] Model clipping Is it possible to define a model clip such that it makes a hole in geometry? In other words can the clipping planes be defined such that the planes face outward? In particular I want to put holes in the terrain to give access to basements, etc. And when it does clip, does it slice triangles or just render or not render the entire triangle? Thanks in advance! Dave Yazel =========================================================================== 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". =========================================================================== 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". =========================================================================== 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".
