WarpZones:

WarpZones:
- entities with a camera_transform function field
  arguments: vector origin, vector angles
  global input: v_forward, v_right, v_up = camera orientation
  return value: new origin
  global output: v_forward, v_right, v_up = new camera orientation
  global output: trace_endpos = origin on "remote side" for culling purposes
- on server, only the trace_endpos return value is used, and '0 0 0' angles are passed, and only the trace_endpos is used (this may be subject to change)
- a warpzone is an above described entity that contains a surface of a shader that uses the keywords dp_camera AND dp_refract
- a camera is an above described entity that contains a surface of a shader that JUST uses the keyword dp_camera
- in case of a camera, preferably the camera_transform function shall not use the input values (except for use for certain special effects)
- rendering of these warpzones is not recursive (yet)
- the warpzones do not have any impact on gameplay - QC support code is needed both on client and server
- example support code will be committed to Nexuiz SVN
- the interface is not stable yet and may be subject to change

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@10035 d7cf8633-e32d-0410-b094-e92efae38249
::stable-branch::merge=f2467d484c38a13d23bb92f91c19a9d6a71f7bec