pixel-editor/js/_getCursorPosition.js

//get cursor position relative to canvas
function getCursorPosition(e) {
	var x;
	var y;

	if (e.pageX != undefined && e.pageY != undefined) {
		x = e.pageX;
		y = e.pageY;
	}
	else {
		x = e.clientX + document.body.scrollLeft + document.documentElement.scrollLeft;
		y = e.clientY + document.body.scrollTop + document.documentElement.scrollTop;			
	}

	x -= canvas.offsetLeft;
	y -= canvas.offsetTop;

	return [x,y];
}

// TODO: apply the function below to every getCursorPosition call

// TODO: FIX THIS BELOW

//get cursor position relative to canvas
function getCursorPositionRelative(e, layer) {
	var x;
	var y;
	
	if (e.pageX != undefined && e.pageY != undefined) {
		x = e.pageX;
		y = e.pageY;
	}
	else {
		x = e.clientX + document.body.scrollLeft + document.documentElement.scrollLeft;
		y = e.clientY + document.body.scrollTop + document.documentElement.scrollTop;			
	}

	x -= layer.canvas.offsetLeft;
	y -= layer.canvas.offsetTop;

	return [x,y];
}