Function IsRoomVisible

Descent3/TelComAutoMap.cpp:419–445

Returns true if the external room is in the view cone Else returns false

// Returns true if the external room is in the view cone
// Else returns false
bool IsRoomVisible(room *rp, float *nearz) {
  g3Point pnt;
  uint8_t ccode;

  vector corners[8];

  MakePointsFromMinMax(corners, &rp->min_xyz, &rp->max_xyz);

  *nearz = 90000000;
  uint8_t andbyte = 0xff;
  for (int t = 0; t < 8; t++) {
    g3_RotatePoint(&pnt, &corners[t]);

    if (pnt.p3_z < *nearz)
      *nearz = pnt.p3_z;

    ccode = g3_CodePoint(&pnt);
    if (!ccode)
      return true;
    andbyte &= ccode;
  }

  if (andbyte)
    return false;

  return true;
}

void TCAMRenderRoom(int roomnum) {
  ASSERT(Rooms[roomnum].used);