topical media & game development
#graphic-flex-image-effects-03-Flex-DrawTest.ax
#graphic-flex-image-effects-03-Flex-DrawTest.ax
[swf]
[flash]
flex
package {
import flash.display.Bitmap;
import flash.display.BitmapData;
import flash.display.Sprite;
import flash.events.KeyboardEvent;
import flash.geom.ColorTransform;
import flash.geom.Matrix;
import flash.ui.Keyboard;
[SWF(width=600, height=400, backgroundColor=0x000000)]
Demonstrates BitmapData's draw() command by duplicating the entirety of the stage using draw()
whenever the space bar is pressed. A smaller copy is also drawn onto the stage to show how draw()
can be used to transform the pixels in the image being drawn.
public class @ax-graphic-flex-image-effects-03-Flex-DrawTest extends Sprite {
private var _circle:Sprite;
private var _bitmapData:BitmapData;
Constructor. Creates bitmap that will be drawn into and circle that will follow the mouse.
A listener is also set up to handle then a key is pressed.
public function @ax-graphic-flex-image-effects-03-Flex-DrawTest() {
createBitmap();
createCircle();
stage.addEventListener(KeyboardEvent.KEY_DOWN, onStageKeyDown);
}
Creates bitmap data that the stage contents will be drawn into and adds this to the stage.
private function createBitmap():void {
_bitmapData = new BitmapData(stage.stageWidth, stage.stageHeight, true, 0x00000000);
var bitmap:Bitmap = new Bitmap(_bitmapData);
addChild(bitmap);
}
Creates a circle shape that is set to follow the mouse as it moves.
private function createCircle():void {
_circle = new Sprite();
_circle.graphics.beginFill(0xFF0000);
_circle.graphics.drawCircle(0, 0, 25);
_circle.graphics.endFill();
addChild(_circle);
_circle.x = stage.mouseX;
_circle.y = stage.mouseY;
_circle.startDrag();
}
Handler for when a key is pressed. If it is the space bar, the current stage view is drawn into bitmap.
parameter: event Event dispatched by stage.
private function onStageKeyDown(event:KeyboardEvent):void {
if (event.keyCode == Keyboard.SPACE) {
_bitmapData.draw(stage);
// added in step 2, this enables the scaling down of a smaller copy of the stage image data
var matrix:Matrix = new Matrix();
matrix.scale(.5, .5);
// added in step 3, this moves the smaller copy to the lower right corner of the bitmap
matrix.translate(300, 200);
// added in step 4, this inverts the colors of the smaller copy
var transform:ColorTransform = new ColorTransform(-1, -1, -1, 1, 255, 255, 255);
_bitmapData.draw(stage, matrix, transform);
// transform the current color of the circle
transform = new ColorTransform();
transform.color = Math.random()*0xFFFFFF;
_circle.transform.colorTransform = transform;
}
}
}
}
(C) Æliens
04/09/2009
You may not copy or print any of this material without explicit permission of the author or the publisher.
In case of other copyright issues, contact the author.
