User Guide

BitmapData (flash.display.BitmapData) 305
copyPixels (BitmapData.copyPixels method)
public copyPixels(sourceBitmap:BitmapData, sourceRect:Rectangle,
destPoint:Point, [alphaBitmap:BitmapData], [alphaPoint:Point],
[mergeAlpha:Boolean]) : Void
Provides a fast routine to perform pixel manipulation between images with no stretching,
rotation, or color effects. This method copies a rectangular area of a source image to a
rectangular area of the same size at the destination point of the destination BitmapData
object.
If include the
alphaBitmap and alphaPoint parameters, you can use a secondary image as an
alpha source for the source image. If the source image has alpha data, both sets of alpha data
are used to composite pixels from the source image to the destination image. The
alphaPoint
parameter is the point in the alpha image that corresponds to the upper-left corner of the
source rectangle. Any pixels outside the intersection of the source image and alpha image are
not copied to the destination image.
The
mergeAlpha property controls whether or not the alpha channel is used when a
transparent image is copied onto another transparent image. To simply copy pixels (with no
alpha used), set the
mergeAlpha property to false. Then all pixels are copied from source to
destination. By default, the
mergeAlpha property is true.
Availability: ActionScript 1.0; Flash Player 8
Parameters
sourceBitmap:flash.display.BitmapData - The input bitmap image from which to copy
pixels. The source image can be a different BitmapData instance, or it can refer to the current
BitmapData instance.
sourceRect:flash.geom.Rectangle - A rectangle that defines the area of the source image
to use as input.
destPoint:flash.geom.Point - The destination point, that represents the upper-left corner
of the rectangular area where the new pixels are placed.
alphaBitmap:flash.display.BitmapData [optional] - A secondary, alpha BitmapData
object source.
alphaPoint:flash.geom.Point [optional] - The point in the alpha BitmapData object
source that corresponds to the upper-left corner of the
sourceRect parameter.
mergeAlpha:Boolean [optional] - A Boolean value:To use the alpha channel, set the value to
true. To copy pixels with no alpha channel, set the value to false.