Merge pull request #1826 from scooterw/fix_mouse_position_relative

attempt to address regressions from #1684, #1745

src/dom/DomEvent.js

@@ -132,13 +132,30 @@ L.DomEvent = {
 
 	getMousePosition: function (e, container) {
 
-		var body = document.body,
+		var ie7 = L.Browser.ie7,
+		    body = document.body,
 		    docEl = document.documentElement,
-		    x = e.pageX ? e.pageX : e.clientX + body.scrollLeft + docEl.scrollLeft,
-		    y = e.pageY ? e.pageY : e.clientY + body.scrollTop + docEl.scrollTop,
-		    pos = new L.Point(x, y);
+		    x = e.pageX ? e.pageX - body.scrollLeft - docEl.scrollLeft: e.clientX,
+		    y = e.pageY ? e.pageY - body.scrollTop - docEl.scrollTop: e.clientY,
+		    pos = new L.Point(x, y),
+		    rect = container.getBoundingClientRect(),
+		    left = rect.left - container.clientLeft,
+		    top = rect.top - container.clientTop;
+
+		// webkit (and ie <= 7) handles RTL scrollLeft different to everyone else
+		// https://code.google.com/p/closure-library/source/browse/trunk/closure/goog/style/bidi.js
+		if (!L.DomUtil.documentIsLtr() && (L.Browser.webkit || ie7)) {
+			left += container.scrollWidth - container.clientWidth;
+
+			// ie7 shows the scrollbar by default and provides clientWidth counting it, so we
+			// need to add it back in if it is visible; scrollbar is on the left as we are RTL
+			if (ie7 && L.DomUtil.getStyle(container, 'overflow-y') !== 'hidden' &&
+			           L.DomUtil.getStyle(container, 'overflow') !== 'hidden') {
+				left += 17;
+			}
+		}
 
-		return (container ? pos._subtract(L.DomUtil.getViewportOffset(container)) : pos);
+		return pos._subtract(new L.Point(left, top));
 	},
 
 	getWheelDelta: function (e) {