Question

How can I find a pixel position, based in its color, within a bitmapdata?

Say, we have a path drawed (a movieclip), we make it a bitmapdata.

The path´s color is red.

How can I find a given pixel red, within that bitmapdata?

Answer 1

Assuming the pixel you are looking for is a specific color, you would iterate through the BitmapData and compare pixels using getPixel() or getPixel32() to test each pixel against your target color. Something like this:

var data:BitmapData; //your bitmap data, however you get it
var targetColor:uint = 0xFF6600;

var coords:Point = null;

for(var i:int = 0; i < data.width; i++) {
    for(var j:int = 0; j < data.height; j++) {
        var testPixel:uint = data.getPixel(i,j);
        if(testPixel == targetColor) {
            coords = new Point(i, j);
            break;
        }
    }
} 

Hope this helps!