Senocular's Directional Motion Blur

[pajhonka]

I'm building banners in AS2 and I've tried to customize Senocular's very handy directional motion blur.

The problem I'm having is I can't make this code reusable- I want to use it in a more linear fashion for banners rather then dynamically with mouse clicks. Has anyone had any luck using this in a timeline? Thanks!

This is my attempt to customize at the moment (old_loc is coming up as undefined, which in turn makes new_loc NaN):

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:Point;
var blur_filter:BlurFilter;
var target_loc:Point;
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_filter);
    // 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:Point, pt2:Point):Number
{
    var dx = pt2.x - pt1.x;
    var dy = pt2.y - pt1.y;
    return Math.atan2(dy, dx);
}