[JAVA3D] View Projection values

[Zak Nixon]

I am trying to get the values for the view volumes for the parallel and perspective views.   I am currently studying OpenGL, and trying to make an application that will show the viewing volumes in a 3D application.   How can I retrieve these values, for example in OpenGL       glFrustrum(top,bottom,left,right,near,far);     glPerspective(fovy,aspectRatio, near,far);     glOrtho(top,bottom,left,right,near, far);     and so on.   Thanks for the help   Zak