docs: function(tree, alsoRemovecoplanarFront) {
              var node = this, stack = [];
              do {
                  if(node.polygontreenodes.length > 0) {
                      tree.rootnode.clipPolygons(node.polygontreenodes, alsoRemovecoplanarFront);
                  }
                  if(node.front) stack.push(node.front);
                  if(node.back) stack.push(node.back);
                  node = stack.pop();
              } while(typeof(node) !== 'undefined');
          }