View Full Version : To cutoff portion from a object

10-10-2004, 08:47 PM
I am creating simple 3D application. Showing some of the objects such as Rectangle, Triangle etc.

Now I want to cut a portion of an Object and want to make the cutoff area transparent so as to view the other objects from the transparent portion.

For e.g.
Consider A is Rectangle
B is Quadrangle and
C is Circle.

A is on the front screen
C is behind A.
So when I view directly I can see only A, until I rotate, I am unable to view C.

Now, I want to cut B size object from A, making Quad size hole in A, so that I can view the portion of C object from the hole.

So, I want to know from OpenGL Experts is there any in-built functions or properties through which I can cut object using another object and Can I make the cutoff area transparent so that I can view portions of all other objects behind the cutoff area from the cutoff portion.

Please write back to me at dnomula@yahoo.co.in.

Deepa Nomula.
Software Consultant,
CyberMarine Knowledge Systems Pvt. Ltd
Navi Mumbai

10-10-2004, 09:15 PM
This is not an advanced question.

Do a search (on google and this forum) for "CSG". You can do what you want in a number of different ways (stencil, depth test, CSG) but learning about CSG methods will probably give you the larger benefit.