Calculating Position of Rectangle Corners

Question

Hello again everyone - I'm in the middle of attempting to write my own collision detection algorithm because the built in 'hitTestObject' function seems to be incredibly inaccurate (it's registering 'hits' when the objects are still a considerable distance from each other).
I need to be able to calculate the position of each of the 4 corners of a rectangle, based on its rotation. Obviously one of the corners will simply be the rectangle's x and y coordinates. I have made a little test program to make sure I am calculating the positions of the corners accurately - it works when the rectangle is rotated to 0, 90, 180 and 270 degrees, but produces strange results for any other angles...
I have attached the program at the bottom, but here is the code:
package
    import flash.display.MovieClip;
    import flash.geom.Point;
    public class CornerFinder extends MovieClip
        //vars
        var myRect:MovieClip;
        //constructor
        public function CornerFinder():void
            myRect = new MyRectangle();
            myRect.x = stage.stageWidth/2;
            myRect.y = stage.stageHeight/2;
            myRect.rotationZ = 270;
            addChild(myRect);
            AddCornerMarkers();
        private function AddCornerMarkers():void
            //The rotation of the rectangle in radians
            var rectRotation = myRect.rotationZ*(Math.PI/180);
            var corners:Array = new Array();
            corners[0] = new Point(myRect.x, myRect.y);
            corners[1] = new Point( (myRect.x + myRect.width * Math.cos(-rectRotation)), (myRect.y + myRect.height*Math.sin((rectRotation) )) );
            corners[2] = new Point( (myRect.x + myRect.width * Math.sin(-rectRotation)), (myRect.y + myRect.height*Math.cos((rectRotation) )) );
            corners[3] = new Point(corners[2].x + (corners[1].x - corners[0].x) , corners[2].y + (corners[1].y - corners[0].y));
            for(var i:uint = 0; i < corners.length; i++)
                var marker:MovieClip = new CornerMarker();
                marker.x = corners[i].x - marker.width/2;
                marker.y = corners[i].y - marker.height/2;
                trace("Adding marker at: " + marker.x + ", " + marker.y);
                addChild(marker);
MyRectangle, as you may have guessed is a simple rectangular symbol that is in the library of my fla file. The CornerMarker is just a red circle symbol.
Can anyone see what the problem is? I thought if it worked for the 'main' angles (e.g. 0, 90, 180, etc) it would work for everything in between, but apparently not...

Answer 1

you misunderstand.
try:
package
    import flash.display.MovieClip;
    import flash.geom.Point;
    public class CornerFinder extends MovieClip
        //vars
        var myRect:MovieClip;
        //constructor
        public function CornerFinder():void
            myRect = new MyRectangle();
            myRect.x = stage.stageWidth/2;
            myRect.y = stage.stageHeight/2;
            myRect.rotationZ = 270;
            addChild(myRect);
            AddCornerMarkers();
        private function AddCornerMarkers():void
            //The rotation of the rectangle in radians
            var rectRotation = myRect.rotationZ*(Math.PI/180);
            var corners:Array = new Array();
myRect.rotationZ=0;
            corners[0] = new Point(myRect.x, myRect.y);
corners[1] = new Point( (myRect.x + myRect.width *
Math.cos(rectRotation)), (myRect.y +
myRect.width*Math.sin((rectRotation) )) );
           // corners[2] = new Point( (myRect.x + myRect.width * Math.sin(-rectRotation)), (myRect.y + myRect.height*Math.cos((rectRotation) )) );
          //  corners[3] = new Point(corners[2].x + (corners[1].x - corners[0].x) , corners[2].y + (corners[1].y - corners[0].y));
myRect.rotationZ=rectRotation*180/Math.PI;
            for(var i:uint = 0; i < corners.length; i++)
                var marker:MovieClip = new CornerMarker();
                marker.x = corners[i].x - marker.width/2;
                marker.y = corners[i].y - marker.height/2;
                trace("Adding marker at: " + marker.x + ", " + marker.y);
                addChild(marker);