Function ClipSurfaceElement

editor/editor_lighting.cpp:1519–1568

}

void ClipSurfaceElement(vector *surf_verts, rad_element *ep, vector *clip_verts, int nv) {
  rad_point src_verts[50];
  rad_point dest_verts[50];
  rad_point *slist, *dlist;
  uint8_t and = 0xff;
  uint8_t or = 0;
  int i;

  ASSERT(nv < 50);

  ep->flags = 0;

  SetRadClipLines(&clip_verts[0], &clip_verts[1], &clip_verts[2], &clip_verts[3]);

  for (i = 0; i < nv; i++) {
    src_verts[i].pos = surf_verts[i];
    src_verts[i].code = CodeRadPoint(&src_verts[i]);
  }

  for (i = 0; i < nv; i++) {
    and &= src_verts[i].code;
    or |= src_verts[i].code;
  }

  if (and) {
    // This element is not even in the face, ignore it
    ep->flags |= EF_IGNORE;
    ep->num_verts = 0;
    return;
  }

  int pnv = nv, nnv;
  slist = src_verts;
  dlist = dest_verts;

  nnv = ClipRadPointList(&slist, &dlist, &pnv, or);

  ep->num_verts = nnv;

  if (ep->num_verts == 0)
    ep->flags |= EF_IGNORE;
  else {
    ep->verts = (vector *)mem_malloc(sizeof(vector) * nnv);
    ASSERT(ep->verts);

    for (i = 0; i < nnv; i++) {
      ep->verts[i] = dlist[i].pos;
    }
  }
}

// Takes a points and clips all its viewpoints so they fit into the view frustum
// Puts the new clipped list in dest