PICTURE Shikaku
   SET AREA COLOR 2
   PLOT AREA:  0,0;1,1;2,0
   SET AREA COLOR 3
   PLOT AREA:  2,0;1,1;2,2
   SET AREA COLOR 4
   PLOT AREA: 2,2;1,1;0,2
   SET AREA COLOR 5
   PLOT AREA: 0,2;1,1;0,0
END PICTURE

SET WINDOW -3,3,-3,3
DRAW grid
DRAW Shikaku
LET theta=ATN(-1)
PLOT LINES: -3,3;3,-3
DRAW Shikaku WITH ROTATE(-theta)*SCALE(1,-1)*ROTATE(theta)
PLOT TEXT ,AT 0.8,2.1, USING "##":"‚`"
PLOT TEXT ,AT -1.2,0.1, USING "##":"‚a"
END