Rotate Canvas from center code

var point:Point=new Point(myMC.x+myMC.width/2, myMC.y+myMC.height/2);
var m:Matrix=myMC.transform.matrix;
m.tx -= point.x;m.ty -= point.y;
m.rotate (45*(Math.PI/180));
m.tx += point.x;
m.ty += point.y;
myMC.transform.matrix=m;