Function PhysPastPortal

physics/findintersection.cpp:4438–4451

}

bool PhysPastPortal(const room *rp, portal *pp) {
  // If we don't render the portal's faces, then we see through it
  if (!(pp->flags & PF_RENDER_FACES))
    return 1;

  // Check if the face's texture has transparency
  face *fp = &rp->faces[pp->portal_face];
  int bm_handle = GetTextureBitmap(fp->tmap, 0);

  if (GetFaceAlpha(fp, bm_handle))
    return 1; // Face has alpha or transparency, so we can see through it
  else
    return 0; // Not transparent, so no render past
}

int fvi_room(int room_index, int from_portal, int room_obj) {
  vector hit_point; // where we hit