Database Traversals

Performer operates on its scene graph via traversals, where nodes are recursively visited. Traversals occur in the application, cull, and draw stages, each performing different operations. Various default operations are performed on the graph automatically; application-specific operations can be performed by traversal callbacks. e.g.:

	int draw_callback(pfTraverser *trav,void *travData);

	node->setTravFuncs(PFTRAV_DRAW,draw_callback,NULL);
	node->setTravData(PFTRAV_DRAW,node_data);

causes draw_callback() to be called in the draw stage when node is visited. Note - node will not be visited in the draw stage if it has been culled.

Navigation example using traversal callback

Table of contents

Last modified 5 February 1996.

Dave Pape, pape@evl.uic.edu