问如何在ActionScript3.0中捕捉线条？

EN

function countPixels(shape:DisplayObject):int
{
    var bd:BitmapData = new BitmapData(shape.width, shape.height);
    bd.draw(shape);

    //here you get sequence of ARGB-packed colors in vector
    var pixels:Vector.<uint> = bd.getVector(bd.rect);

    //AFAIK, fastest method to traverse vector is 'for' loop
    var pixel:uint;
    var filledCount:int = 0;
    for (var i:int = pixels.length - 1; i >= 0; i--)
    {
        pixel = pixels[i];
        //pixel is 32-bit ARGB color value, test upper 8 bits (alpha):
        if ((pixel >> 24) > 0) filledCount++;
    }
    return filledCount;
}