Portal tracer glitch

[stohrendorf]

The portal tracer stops too early when the camera is close to a portal and oriented nearly parallel to it.

[stohrendorf]

Maybe this will work:

• For each pair of vertices (A,B) of the portal:
  • if (A--B) does not cross the view plane (aka sign(A.z) == sign(B.z)), do nothing.
  • if A.x<0 && B.x<0, extend bounding box X=-1,
  • else if A.x>0 && B.x>0, extend bounding box X=1
  • else extend bounding box X=[-1, 1]
  • same for Y