Previously in Flash MX and earlier, if we want to do a precise hit collision, we will need to trace the image and create an invisible layer to insert in the button hit state.
Now, with BitmapData.hitTest(), we no longer need to do this. What we need is to import an transparent background bitmap and convert it into a BitmapData Object.
In the sample example below, i import in a bitmap and give it a linkage ID in the library so that i can use the BitmapData.loadBitmap() to load the bitmap.
Next i perform a pixel-level hit detection between the loaded bitmap and another bitmap image.
// create empty movieclip to store bitmap for precise hittest var dm:MovieClip=createEmptyMovieClip("dm",getNextHighestDepth());
// loads a bitmap tat is identified by a linkage ID in the library var db:BitmapData=BitmapData.loadBitmap("porsche"); // create another bitmap(1 by 1 pixel) for bitmapdata hittest comparsion var cb:BitmapData=new BitmapData(1,1,false,0x00000000);
// attach the bitmap to the movieclip
dm.attachBitmap(db,1);
// define pixel location in 2 BitmapData instance var dp:Point=new Point(); var cp:Point=new Point();
// define first pixel location point in first BitmapData instance
dp.x=dm._x;
dp.y=dm._y;
this.onEnterFrame=function():Void{
// define first pixel location point in second BitmapData instance
// set to _xmouse and _ymouse
cp.x=_xmouse;
cp.y=_ymouse;
// performs pixel-level hit detection if(cb.hitTest(cp,255,db,dp,255)){
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