flash on 2011-5-17

...
@author ton

by ton 17 May 2011

Embed

package {
	import flash.display.Sprite;
	import flash.events.Event;
	import flash.geom.Matrix;

	/**
	 * ...
	 * @author ton
	 */
	public class Main extends Sprite {

		public function Main():void {
			if (stage)
				init();
			else
				addEventListener(Event.ADDED_TO_STAGE, init);
		}

		private function init(e:Event = null):void {
			removeEventListener(Event.ADDED_TO_STAGE, init);
			// entry point

			var mc:Sprite = new Sprite();

			mc.graphics.beginFill(0xff0000);
			mc.graphics.drawRect(0, 0, 100, 100);
			mc.graphics.endFill();

			mc.x = mc.y = 100;

			addChild(mc);

			var tx:Number = mc.x;
			var ty:Number = mc.y;
			var rotate:Number = Math.PI / 4;

			var mat1:Matrix = new Matrix(1, 0, 0, 1, mc.x, mc.y);
			var mat2:Matrix = new Matrix(1, 0, 0, 1, mc.x + mc.width, mc.y);
			var mat3:Matrix = new Matrix(1, 0, 0, 1, mc.x, mc.y + mc.height);
			var mat4:Matrix = new Matrix(1, 0, 0, 1, mc.x + mc.width, mc.y + mc.height);

			mat1 = rotateMat(mat1, tx, ty, rotate);
			trace(mat1);
			mat2 = rotateMat(mat2, tx, ty, rotate);
			trace(mat2);
			mat3 = rotateMat(mat3, tx, ty, rotate);
			trace(mat3);
			mat4 = rotateMat(mat4, tx, ty, rotate);
			trace(mat4);

			mc.transform.matrix = mat1;

		}

		private function rotateMat(mat:Matrix, tx:Number, ty:Number, rotate:Number):Matrix {
			var mat:Matrix = mat.clone();

			mat = translatePost( -tx, -ty, mat);
			mat = rotatePost(rotate, mat);
			mat = translatePost(tx, ty, mat);

			return mat;
		}
		
		private function translatePost(tx:Number, ty:Number, mat:Matrix):Matrix {
			return new Matrix(mat.a, mat.b, mat.c, mat.d, mat.tx + tx, mat.ty + ty);
		}
		
		private function rotatePost(rotateRad:Number, mat:Matrix):Matrix {
			var cos:Number = Math.cos(rotateRad);
			var sin:Number = Math.sin(rotateRad);
			
			return new Matrix(mat.a * cos + mat.b * -sin, mat.a * sin + mat.b * cos, mat.c * cos + mat.d * -sin,
								mat.c * sin + mat.d * cos, mat.tx * cos + mat.ty * -sin, mat.tx * sin + mat.ty * cos);
		}
		
		
	}

}