[RESOLVED] BitmapData.hitTest with slanted lines

[Tartarus]

Hi,
I'm trying to perform a BitmapData hitTest between a dynamically loaded BitmapData object and a dynamically created slanted line. The problem is, even when I draw the line as BitmapData, it still hitTests the entire bounding box of the slanted line.

What I start with is

public var Line:Shape = new Shape();

Then I make a new line every frame between two points:

Line.graphics.clear();
Line.graphics.lineStyle(1, 0xFF0000, 1);
Line.graphics.moveTo(mc.x, mc.y)					Line.graphics.lineTo(mouseX,mouseY)

Then, draw it to a bitmapData:

var bd:BitmapData = new BitmapData(Line.width, Line.height);
bd.draw(Line);

Then, the hitTest:

if (Object.bitmapData.hitTest(FirstPoint(works), 1, bd, new Point(0,0))){
  //execute code
}

I think the problem's with the 'second point', but the livedocs and an hour of google-searching have yielded nothing :/

[Orkahm52]

HitTest() will always check the bounding box no matter the shape of the contents, movie clip and bitmap data alike. So instead of using a hitTest() you could use getPixel();

if (Object.bitmapData.getPixel(point.x, point.y)==0xFF0000){
  //execute code
}

Though that would only work if the colour is always the same, so you might want to check a range of colours like so:

if (Object.bitmapData.getPixel(point.x, point.y)>0x660000 || Object.bitmapData.getPixel(point.x, point.y)<0xFF0000){
  //execute code
}

~Ork.

[tonypa]

No, if you use 2 bitmapdata objects, you can find hittest between actual pixels and not just bounding boxes:
http://www.8bitrocket.com/newsdispla...?newspage=9947
In AS3 displayObject has 2 methods (hitTestObject and hitTestPoint) and bitmapData has a method called hitTest.

[Tartarus]

... and hitTest between two BitmapData objects is what I'm trying to do... but somehow it hitTests the entire bounding box rather than the actual bitmapData, which is a slanted line.

[tonypa]

Maybe you need to make the bitmapdatas transparent first.

[Tartarus]

Both bitmapData's transparent properties are true, I checked.

EDIT: Apparently when creating a new bitmapData, I was supposed to indicate that the fill was 0x000000(nothing), because by default my bitmapData became a white rectangle, which consituted the problem.

Thanks a lot, Tonypa