Function RotateAllExternalRooms

Descent3/render.cpp:688–738

Prerotates all external room points and caches them

}
// Prerotates all external room points and caches them
void RotateAllExternalRooms() {
  // Build the external room list if needed
  if (N_external_rooms == -1) {
    // Set up our z wall
    float zclip = (Detail_settings.Terrain_render_distance) * Matrix_scale.z;
    g3_SetFarClipZ(zclip);
    N_external_rooms = 0;

    int i;
    for (i = 0; i <= Highest_room_index; i++) {
      if ((Rooms[i].flags & RF_EXTERNAL) && Rooms[i].used) {
        External_room_list[N_external_rooms++] = i;
      }
    }
    ASSERT(N_external_rooms < MAX_EXTERNAL_ROOMS); // Get Jason if hit this
    // Rotate all the points
    vector corners[8];
    for (i = 0; i < N_external_rooms; i++) {
      int roomnum = External_room_list[i];
      room *rp = &Rooms[roomnum];
      MakePointsFromMinMax(corners, &rp->min_xyz, &rp->max_xyz);

      uint8_t andbyte = 0xff;
      g3Point pnt;
      External_room_codes[i] = 0xff;
      External_room_project_net[i] = 0;
      bool behind = 0;
      bool infront = 0;
      for (int t = 0; t < 8; t++) {
        g3_RotatePoint(&pnt, &corners[t]);
        External_room_codes[i] &= pnt.p3_codes;
        if (pnt.p3_codes & CC_BEHIND)
          behind = true;
        else
          infront = true;
        pnt.p3_codes &= ~CC_BEHIND;
        g3_ProjectPoint(&pnt);
        External_room_corners[i][t].x = pnt.p3_sx;
        External_room_corners[i][t].y = pnt.p3_sy;
      }
      if (infront && behind) {
        External_room_codes[i] = 0;
        External_room_project_net[i] = 1;
      } else {
        if (behind) {
          External_room_codes[i] = CC_BEHIND;
        }
      }
    }
  }
}

void CheckFogPortalExtents(int roomnum, int portalnum) {
  room *rp = &Rooms[roomnum];