Copyright 1992 Digital Equipment Corporation.
Distributed only by permission.
Last modified on Wed Jun 23 12:07:25 PDT 1993 by steveg
modified on Fri Aug 7 07:17:10 PDT 1992 by mhb
INTERFACE GraphAnim;
IMPORT GraphVBT, RefList;
<* PRAGMA LL *>
This interface contains a collection of procedures for animating motions on
a collection of GraphVBT.Vertex. Even if a vertex is mentioned multiple
times in the list, it is only moved once.
PROCEDURE Rotate (center : GraphVBT.Vertex;
angle : REAL;
vertices : RefList.T (* of GraphVBT.Vertex *));
<* LL.sup = RefList.First(SELF.vertices).graph.mu *>
Rotate vertices around center by angle degrees. Positive
degrees move in the clockwise direction when x increases to the right
and y increases downward. Reversing the polarity of x or y reverses
the direction of rotation. Reversing the polarity of both x and y,
leaves the direction of rotation unchanged.
PROCEDURE MoveAlongEdges (edges : RefList.T (* of GraphVBT.Edge *);
vertices: RefList.T (* of GraphVBT.Vertex *));
<* LL.sup = RefList.First(SELF.vertices).graph.mu *>
Move vertices along edges. The time spent moving along each edge is
roughly proportionate to the edge's length.
END GraphAnim.