Function SplitFace

editor/HRoom.cpp:2896–2994

Splits a face into two pieces Parameters: rp,facenum - the face to split v0,v1 - the two verts that will form the new edge

// Parameters:	rp,facenum - the face to split
//					v0,v1 - the two verts that will form the new edge
void SplitFace(room *rp, int facenum, int v0, int v1) {
  face *fp = &rp->faces[facenum], *nfp;
  int first_new_face, i;

  if (v0 == v1) {
    OutrageMessageBox("You cannot split a face using the same point twice.");
    return;
  }

  if (v1 < v0) {
    int t = v1;
    v1 = v0;
    v0 = t;
  }

  if (v1 == (v0 + 1) % fp->num_verts) {
    OutrageMessageBox("You cannot split a face using two adjacent points.");
    return;
  }

  if (fp->num_verts == 3) {
    OutrageMessageBox("Face %d has three verts and cannot be split.", facenum);
    return;
  }

  if (fp->portal_num != -1) {
    OutrageMessageBox("You cannot split a face that's part of a portal.");
    return;
  }

  if (fp->flags & (FF_HAS_TRIGGER + FF_FLOATING_TRIG)) {
    OutrageMessageBox("You cannot split a face that has a trigger.");
    return;
  }

  Disable_editor_rendering = 1;

  // Add new faces
  first_new_face = RoomAddFaces(rp, 2);

  // Reset pointer to our old face
  fp = &rp->faces[facenum];

  // Set up each face
  bool ok[2];
  for (i = 0, nfp = &rp->faces[first_new_face]; i < 2; i++, nfp++) {
    int nv, startv;

    if (i == 0) {
      nv = v1 - v0 + 1;
      startv = v0;
    } else {
      nv = fp->num_verts - (v1 - v0) + 1;
      startv = v1;
    }

    InitRoomFace(nfp, nv);