topical media & game development
#graphic-flex-image-effects-04-Flex-ColorReplaceTest.ax
#graphic-flex-image-effects-04-Flex-ColorReplaceTest.ax
[swf]
[flash]
flex
package {
import flash.display.BitmapData;
import flash.display.BitmapDataChannel;
import flash.filters.BlurFilter;
import flash.geom.ColorTransform;
import flash.geom.Point;
[SWF(width=300, height=300, backgroundColor=0xFFFFFF)]
public class @ax-graphic-flex-image-effects-04-Flex-ColorReplaceTest extends graphic_flex_image_effects_04_Flex_AbstractImageLoader {
private static const COLOR_TO_REPLACE:uint = 0x819AD3;
private static const TOLERANCE:uint = 32;
private var _originalData:BitmapData;
private var _isolatedData:BitmapData;
Constructor. Passes path of image to load to super class.
public function @ax-graphic-flex-image-effects-04-Flex-ColorReplaceTest() {
super("graphic-flex-image-effects-04-assets-goat.jpg");
}
Run after the image loads in super class. This creates an image of clouds, then removes pixels from
this image by using multiple calls to the threshold() method. The resulting image is copied into the
loaded image's data.
override protected function runPostImageLoad():void {
_originalData = _loadedBitmap.bitmapData;
// creates a cloud image
_isolatedData = createCloudImage(_originalData.width, _originalData.height);
// finds the brightness to replace in each channel
var red:uint = COLOR_TO_REPLACE>>16 & 0xFF;
var green:uint = COLOR_TO_REPLACE>>8 & 0xFF;
var blue:uint = COLOR_TO_REPLACE & 0xFF;
// removes all pixels that are above and bloew the threshold around each channel's required value
applyThreshold("<", Math.max(0, red-TOLERANCE)<<16, 0x00FF0000);
applyThreshold(">", Math.min(255, red+TOLERANCE)<<16, 0x00FF0000);
applyThreshold("<", Math.max(0, green-TOLERANCE)<<8, 0x0000FF00);
applyThreshold(">", Math.min(255, green+TOLERANCE)<<8, 0x0000FF00);
applyThreshold("<", Math.max(0, blue-TOLERANCE), 0x000000FF);
applyThreshold(">", Math.min(255, blue+TOLERANCE), 0x000000FF);
// blurs the clouds image slightly so that the edges where pixels were removed aren't jagggy
_isolatedData.applyFilter(_isolatedData, _isolatedData.rect, new Point(), new BlurFilter(2, 2));
// copies the cloud image into the loaded image
_originalData.copyPixels(_isolatedData, _isolatedData.rect, new Point());
_isolatedData.dispose();
addChild(_loadedBitmap);
}
creates a cloud image using Perlin noise. This will be placed into the keyed out areas of the image.
parameter: width The pixel width of the image to create.
parameter: height The pixel height of the image to create.
returns: The cloud image created.
private function createCloudImage(width:Number, height:Number):BitmapData {
var bitmapData:BitmapData = new BitmapData(width, height, true, 0x00000000);
// noise only created in the red channel
bitmapData.perlinNoise(100, 100, 3, 0, false, true, BitmapDataChannel.RED, true);
// image lightened, with more lightening done in the red channel
var colorTransform:ColorTransform = new ColorTransform(1.5, 1.4, 1.2, 1, 20, 20, 20);
bitmapData.colorTransform(bitmapData.rect, colorTransform);
return bitmapData;
}
Calls theshold() on bitmap data.
parameter: operation The operation to call as required by the threshold() method.
parameter: threshold The threshold value to pass to the threshold() method.
parameter: mask The mask value to pass to the threshold method.
private function applyThreshold(
operation:String,
threshold:uint,
mask:uint
):void {
_isolatedData.threshold(
_originalData,
_originalData.rect,
new Point(),
operation,
threshold,
0x00000000,
mask,
false
);
}
}
}
(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.
