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ActionScript:
import flash.geom.*;
import flash.display.BitmapData;
import flash.filters.BlurFilter;

Stage.scaleMode = 'noScale';

var maxBlur:Number = 40;// maximum blur amount for motion blurring
var easeAmount:Number = .75;// amount of easing to be used for movement (0-1)
var maxSize:Number;
var offset:Number;
var blur_bmp:BitmapData;
var rotate_matrix:Matrix = new Matrix();
var blur_rect:Rectangle = new Rectangle();
var blur_point<img align="top" src="images/smilies/tongue.gif" border="0" alt="">oint;
var blur_filter:BlurFilter;
var target_loc<img align="top" src="images/smilies/tongue.gif" border="0" alt="">oint;
var blurred_mc:MovieClip;

function motionBlur(mc:MovieClip, xPos, yPos):Void
{
        //mc._visible = false;
        maxSize = maxBlur + Math.sqrt(mc._width * mc._width + mc._height * mc._height);
        trace("maxSize = " + maxSize);
        offset = maxSize / 2;
        trace("offset = " + offset);
        blur_bmp = new BitmapData(maxSize, maxSize, true, 0);
        this.createEmptyMovieClip("blurred_mc",1);
        blurred_mc.createEmptyMovieClip("image",1);
        blurred_mc.image.attachBitmap(blur_bmp,1,false,true);
        blurred_mc.image._x = -offset;
        blurred_mc.image._y = -offset;
        blur_rect = blur_bmp.rectangle;// rectangle area filter affects
        blur_point = new Point(0, 0);// offset point for filter
        blur_filter = new BlurFilter(0, 0);// filter (blur, starting with no power)
        //http://flash-creations.com/notes/actionscript_eventhandlers.php
        this.onEnterFrame = moveIt(mc);
        target_loc = new Point(xPos, yPos);
}

function moveIt(mc:MovieClip) {
        // get old (current) location of blurred_mc
        var old_loc = new Point(blurred_mc._x, blurred_mc._y);
        trace("old_loc : " + old_loc);
        // develop a new location for blurred_mc with interpolate
        var new_loc = Point.interpolate(old_loc, target_loc, easeAmount);
        trace("new_loc : " + new_loc);
        // assign the new_loc to the position of blurred_mc
        blurred_mc._x = new_loc.x;
        blurred_mc._y = new_loc.y;
        // get the distance from the old loc to the new
        // this will be used to determine how much blur to apply
        var distance = Point.distance(old_loc, new_loc);
        // get the angle from the old loc to the new
        // this will be used to determine the angle of the blur
        var angle = PointAngle(old_loc, new_loc);
        // reset the rotate_matrix to remove any transformations
        // that were applied last frame
        rotate_matrix.identity();
        // rotate the matrix opposite of the angle found between
        // the new and old locations of blurred_mc
        rotate_matrix.rotate(-angle);
        // move the matrix by the offset to account for the
        // centered position of the original click_mc
        rotate_matrix.translate(offset,offset);
        // clear blur_bmp by filling it with empty pixels
        blur_bmp.fillRect(blur_bmp.rectangle,0);
        // draw the rotated, translated click_mc into blur_bmp
        blur_bmp.draw(mc,rotate_matrix);
        // apply the blur power to the blur filter
        blur_filter.blurX = Math.min(maxBlur, distance * 1.5);
        // apply the blur filter to the blur_bmp
        blur_bmp. applyFilter(blur_bmp,blur_rect,blur_point,blur_fil
        ter);
        // rotate blurred_mc to counteract the rotation of
        // rotate_matrix used in draw
        blurred_mc._rotation = angle * 180 / Math.PI;
}

button_mc.onMouseDown = function():Void
{
        motionBlur(click_mc, click_mc._x+=20, click_mc._y+=20);
        trace("CLICK MC X: " + click_mc._x);
        trace("CLICK MC Y: " + click_mc._y);
}
// PointAngle: returns the angle between two points
function PointAngle(pt1<img align="top" src="images/smilies/tongue.gif" border="0" alt="">oint, pt2<img align="top" src="images/smilies/tongue.gif" border="0" alt="">oint):Number
{
        var dx = pt2.x - pt1.x;
        var dy = pt2.y - pt1.y;
        return Math.atan2(dy, dx);
}