diff --git a/src/dom/DomUtil.js b/src/dom/DomUtil.js
index d161b9dd..873b9557 100644
--- a/src/dom/DomUtil.js
+++ b/src/dom/DomUtil.js
@@ -1,5 +1,5 @@
 /*
- * L.DomUtil contains various utility functions for working with DOM
+ * L.DomUtil contains various utility functions for working with DOM.
  */
 
 L.DomUtil = {
@@ -8,48 +8,51 @@ L.DomUtil = {
 	},
 
 	getStyle: function (el, style) {
+
 		var value = el.style[style];
+
 		if (!value && el.currentStyle) {
 			value = el.currentStyle[style];
 		}
+
 		if (!value || value === 'auto') {
 			var css = document.defaultView.getComputedStyle(el, null);
 			value = css ? css[style] : null;
 		}
-		return (value === 'auto' ? null : value);
+
+		return value === 'auto' ? null : value;
 	},
 
 	getViewportOffset: function (element) {
+
 		var top = 0,
 			left = 0,
 			el = element,
-			docBody = document.body;
+			docBody = document.body,
+			pos;
 
 		do {
 			top += el.offsetTop || 0;
 			left += el.offsetLeft || 0;
+			pos = L.DomUtil.getStyle(el, 'position');
 
-			if (el.offsetParent === docBody &&
-					L.DomUtil.getStyle(el, 'position') === 'absolute') {
-				break;
-			}
-			if (L.DomUtil.getStyle(el, 'position') === 'fixed') {
-				top += docBody.scrollTop || 0;
+			if (el.offsetParent === docBody && pos === 'absolute') { break; }
+
+			if (pos === 'fixed') {
+				top  += docBody.scrollTop  || 0;
 				left += docBody.scrollLeft || 0;
 				break;
 			}
-
 			el = el.offsetParent;
+
 		} while (el);
 
 		el = element;
 
 		do {
-			if (el === docBody) {
-				break;
-			}
+			if (el === docBody) { break; }
 
-			top -= el.scrollTop || 0;
+			top  -= el.scrollTop  || 0;
 			left -= el.scrollLeft || 0;
 
 			el = el.parentNode;
@@ -59,15 +62,19 @@ L.DomUtil = {
 	},
 
 	create: function (tagName, className, container) {
+
 		var el = document.createElement(tagName);
 		el.className = className;
+
 		if (container) {
 			container.appendChild(el);
 		}
+
 		return el;
 	},
 
 	disableTextSelection: function () {
+
 		if (document.selection && document.selection.empty) {
 			document.selection.empty();
 		}
@@ -94,12 +101,12 @@ L.DomUtil = {
 	},
 
 	removeClass: function (el, name) {
+
 		function replaceFn(w, match) {
-			if (match === name) {
-				return '';
-			}
+			if (match === name) { return ''; }
 			return w;
 		}
+
 		el.className = el.className
 				.replace(/(\S+)\s*/g, replaceFn)
 				.replace(/(^\s+|\s+$)/, '');
@@ -130,6 +137,7 @@ L.DomUtil = {
 	},
 
 	testProp: function (props) {
+
 		var style = document.documentElement.style;
 
 		for (var i = 0; i < props.length; i++) {
@@ -141,7 +149,7 @@ L.DomUtil = {
 	},
 
 	getTranslateString: function (point) {
-		// On webkit browsers (Chrome/Safari/MobileSafari/Android) using translate3d instead of translate
+		// on WebKit browsers (Chrome/Safari/iOS Safari/Android) using translate3d instead of translate
 		// makes animation smoother as it ensures HW accel is used. Firefox 13 doesn't care
 		// (same speed either way), Opera 12 doesn't support translate3d
 
@@ -153,6 +161,7 @@ L.DomUtil = {
 	},
 
 	getScaleString: function (scale, origin) {
+
 		var preTranslateStr = L.DomUtil.getTranslateString(origin),
 			scaleStr = ' scale(' + scale + ') ',
 			postTranslateStr = L.DomUtil.getTranslateString(origin.multiplyBy(-1));
@@ -160,8 +169,10 @@ L.DomUtil = {
 		return preTranslateStr + scaleStr + postTranslateStr;
 	},
 
-	setPosition: function (el, point, disable3D) {
+	setPosition: function (el, point, disable3D) { // (HTMLElement, Point[, Boolean])
+
 		el._leaflet_pos = point;
+
 		if (!disable3D && L.Browser.any3d) {
 			el.style[L.DomUtil.TRANSFORM] =  L.DomUtil.getTranslateString(point);
 
@@ -176,14 +187,21 @@ L.DomUtil = {
 	},
 
 	getPosition: function (el) {
+		// this method is only used for elements previously positioned using setPosition,
+		// so it's safe to cache the position for performance
 		return el._leaflet_pos;
 	}
 };
 
-L.Util.extend(L.DomUtil, {
-	TRANSITION: L.DomUtil.testProp(['transition', 'webkitTransition', 'OTransition', 'MozTransition', 'msTransition']),
-	TRANSFORM: L.DomUtil.testProp(['transform', 'WebkitTransform', 'OTransform', 'MozTransform', 'msTransform'])
-});
 
-L.DomUtil.TRANSITION_END = (L.DomUtil.TRANSITION === 'webkitTransition' || L.DomUtil.TRANSITION === 'OTransition' ?
-				L.DomUtil.TRANSITION + 'End' : 'transitionend');
+// prefix style property names
+
+L.DomUtil.TRANSFORM = L.DomUtil.testProp(
+		['transform', 'WebkitTransform', 'OTransform', 'MozTransform', 'msTransform']);
+
+L.DomUtil.TRANSITION = L.DomUtil.testProp(
+		['transition', 'webkitTransition', 'OTransition', 'MozTransition', 'msTransition']);
+
+L.DomUtil.TRANSITION_END =
+		L.DomUtil.TRANSITION === 'webkitTransition' || L.DomUtil.TRANSITION === 'OTransition' ?
+		L.DomUtil.TRANSITION + 'End' : 'transitionend';
diff --git a/src/geometry/Point.js b/src/geometry/Point.js
index 7980e1af..318c0dff 100644
--- a/src/geometry/Point.js
+++ b/src/geometry/Point.js
@@ -8,10 +8,17 @@ L.Point = function (/*Number*/ x, /*Number*/ y, /*Boolean*/ round) {
 };
 
 L.Point.prototype = {
+
+	clone: function () {
+		return new L.Point(this.x, this.y);
+	},
+
+	// non-destructive, returns a new point
 	add: function (point) {
 		return this.clone()._add(L.point(point));
 	},
 
+	// destructive, used directly for performance in situations where it's safe to modify existing point
 	_add: function (point) {
 		this.x += point.x;
 		this.y += point.y;
@@ -22,35 +29,36 @@ L.Point.prototype = {
 		return this.clone()._subtract(L.point(point));
 	},
 
-	// destructive subtract (faster)
 	_subtract: function (point) {
 		this.x -= point.x;
 		this.y -= point.y;
 		return this;
 	},
 
-	divideBy: function (num, round) {
-		return new L.Point(this.x / num, this.y / num, round);
+	divideBy: function (num) {
+		return this.clone()._divideBy(num);
 	},
 
-	multiplyBy: function (num, round) {
-		return new L.Point(this.x * num, this.y * num, round);
+	_divideBy: function (num) {
+		this.x /= num;
+		this.y /= num;
+		return this;
 	},
 
-	distanceTo: function (point) {
-		point = L.point(point);
+	multiplyBy: function (num) {
+		return this.clone()._multiplyBy(num);
+	},
 
-		var x = point.x - this.x,
-			y = point.y - this.y;
-
-		return Math.sqrt(x * x + y * y);
+	_multiplyBy: function (num) {
+		this.x *= num;
+		this.y *= num;
+		return this;
 	},
 
 	round: function () {
 		return this.clone()._round();
 	},
 
-	// destructive round
 	_round: function () {
 		this.x = Math.round(this.x);
 		this.y = Math.round(this.y);
@@ -67,8 +75,13 @@ L.Point.prototype = {
 		return this;
 	},
 
-	clone: function () {
-		return new L.Point(this.x, this.y);
+	distanceTo: function (point) {
+		point = L.point(point);
+
+		var x = point.x - this.x,
+			y = point.y - this.y;
+
+		return Math.sqrt(x * x + y * y);
 	},
 
 	toString: function () {
diff --git a/src/layer/ImageOverlay.js b/src/layer/ImageOverlay.js
index feac515c..74d463a0 100644
--- a/src/layer/ImageOverlay.js
+++ b/src/layer/ImageOverlay.js
@@ -94,10 +94,11 @@ L.ImageOverlay = L.Class.extend({
 		    scale = map.getZoomScale(e.zoom),
 		    nw = this._bounds.getNorthWest(),
 		    se = this._bounds.getSouthEast(),
+
 		    topLeft = map._latLngToNewLayerPoint(nw, e.zoom, e.center),
-		    size = map._latLngToNewLayerPoint(se, e.zoom, e.center).subtract(topLeft),
-		    currentSize = map.latLngToLayerPoint(se).subtract(map.latLngToLayerPoint(nw)),
-		    origin = topLeft.add(size.subtract(currentSize).divideBy(2));
+		    size = map._latLngToNewLayerPoint(se, e.zoom, e.center)._subtract(topLeft),
+		    currentSize = map.latLngToLayerPoint(se)._subtract(map.latLngToLayerPoint(nw)),
+		    origin = topLeft._add(size._subtract(currentSize)._divideBy(2));
 
 		image.style[L.DomUtil.TRANSFORM] = L.DomUtil.getTranslateString(origin) + ' scale(' + scale + ') ';
 	},
@@ -105,7 +106,7 @@ L.ImageOverlay = L.Class.extend({
 	_reset: function () {
 		var image   = this._image,
 		    topLeft = this._map.latLngToLayerPoint(this._bounds.getNorthWest()),
-		    size    = this._map.latLngToLayerPoint(this._bounds.getSouthEast()).subtract(topLeft);
+		    size    = this._map.latLngToLayerPoint(this._bounds.getSouthEast())._subtract(topLeft);
 
 		L.DomUtil.setPosition(image, topLeft);
 
diff --git a/src/layer/vector/Path.js b/src/layer/vector/Path.js
index d1d6ce1f..c53948f9 100644
--- a/src/layer/vector/Path.js
+++ b/src/layer/vector/Path.js
@@ -104,8 +104,8 @@ L.Map.include({
 		var p = L.Path.CLIP_PADDING,
 			size = this.getSize(),
 			panePos = L.DomUtil.getPosition(this._mapPane),
-			min = panePos.multiplyBy(-1)._subtract(size.multiplyBy(p)),
-			max = min.add(size.multiplyBy(1 + p * 2));
+			min = panePos.multiplyBy(-1)._subtract(size.multiplyBy(p)._round()),
+			max = min.add(size.multiplyBy(1 + p * 2)._round());
 
 		this._pathViewport = new L.Bounds(min, max);
 	}
diff --git a/src/layer/vector/Polyline.Edit.js b/src/layer/vector/Polyline.Edit.js
index 78490495..ba2738ae 100644
--- a/src/layer/vector/Polyline.Edit.js
+++ b/src/layer/vector/Polyline.Edit.js
@@ -205,6 +205,6 @@ L.Handler.PolyEdit = L.Handler.extend({
 		    p1 = map.latLngToLayerPoint(marker1.getLatLng()),
 		    p2 = map.latLngToLayerPoint(marker2.getLatLng());
 
-		return map.layerPointToLatLng(p1._add(p2).divideBy(2));
+		return map.layerPointToLatLng(p1._add(p2)._divideBy(2));
 	}
 });
diff --git a/src/map/Map.js b/src/map/Map.js
index cd1a6cc8..a7c487e9 100644
--- a/src/map/Map.js
+++ b/src/map/Map.js
@@ -211,7 +211,7 @@ L.Map = L.Class.extend({
 
 		if (!this._loaded) { return this; }
 
-		var offset = oldSize.subtract(this.getSize()).divideBy(2, true);
+		var offset = oldSize._subtract(this.getSize())._divideBy(2)._round();
 
 		if (animate === true) {
 			this.panBy(offset);
@@ -318,7 +318,7 @@ L.Map = L.Class.extend({
 
 			this._sizeChanged = false;
 		}
-		return this._size;
+		return this._size.clone();
 	},
 
 	getPixelBounds: function () {
@@ -620,7 +620,7 @@ L.Map = L.Class.extend({
 	},
 
 	_getNewTopLeftPoint: function (center, zoom) {
-		var viewHalf = this.getSize().divideBy(2);
+		var viewHalf = this.getSize()._divideBy(2);
 		// TODO round on display, not calculation to increase precision?
 		return this.project(center, zoom)._subtract(viewHalf)._round();
 	},
@@ -631,7 +631,7 @@ L.Map = L.Class.extend({
 	},
 
 	_getCenterLayerPoint: function () {
-		return this.containerPointToLayerPoint(this.getSize().divideBy(2));
+		return this.containerPointToLayerPoint(this.getSize()._divideBy(2));
 	},
 
 	_getCenterOffset: function (center) {
diff --git a/src/map/anim/Map.ZoomAnimation.js b/src/map/anim/Map.ZoomAnimation.js
index e36b7e6d..62bb1f02 100644
--- a/src/map/anim/Map.ZoomAnimation.js
+++ b/src/map/anim/Map.ZoomAnimation.js
@@ -17,7 +17,7 @@ L.Map.include(!L.DomUtil.TRANSITION ? {} : {
 		if (!this.options.zoomAnimation) { return false; }
 
 		var scale = this.getZoomScale(zoom),
-			offset = this._getCenterOffset(center).divideBy(1 - 1 / scale);
+			offset = this._getCenterOffset(center)._divideBy(1 - 1 / scale);
 
 		// if offset does not exceed half of the view
 		if (!this._offsetIsWithinView(offset, 1)) { return false; }
diff --git a/src/map/handler/Map.Drag.js b/src/map/handler/Map.Drag.js
index be2dbb59..1344853a 100644
--- a/src/map/handler/Map.Drag.js
+++ b/src/map/handler/Map.Drag.js
@@ -80,7 +80,7 @@ L.Map.Drag = L.Handler.extend({
 	},
 
 	_onViewReset: function () {
-		var pxCenter = this._map.getSize().divideBy(2),
+		var pxCenter = this._map.getSize()._divideBy(2),
 			pxWorldCenter = this._map.latLngToLayerPoint(new L.LatLng(0, 0));
 
 		this._initialWorldOffset = pxWorldCenter.subtract(pxCenter).x;
diff --git a/src/map/handler/Map.ScrollWheelZoom.js b/src/map/handler/Map.ScrollWheelZoom.js
index 905a1c54..329c0caf 100644
--- a/src/map/handler/Map.ScrollWheelZoom.js
+++ b/src/map/handler/Map.ScrollWheelZoom.js
@@ -41,17 +41,17 @@ L.Map.ScrollWheelZoom = L.Handler.extend({
 		if (!delta) { return; }
 
 		var newZoom = zoom + delta,
-			newCenter = this._getCenterForScrollWheelZoom(this._lastMousePos, newZoom);
+			newCenter = this._getCenterForScrollWheelZoom(newZoom);
 
 		map.setView(newCenter, newZoom);
 	},
 
-	_getCenterForScrollWheelZoom: function (mousePos, newZoom) {
+	_getCenterForScrollWheelZoom: function (newZoom) {
 		var map = this._map,
 			scale = map.getZoomScale(newZoom),
-			viewHalf = map.getSize().divideBy(2),
-			centerOffset = mousePos.subtract(viewHalf).multiplyBy(1 - 1 / scale),
-			newCenterPoint = map._getTopLeftPoint().add(viewHalf).add(centerOffset);
+			viewHalf = map.getSize()._divideBy(2),
+			centerOffset = this._lastMousePos._subtract(viewHalf)._multiplyBy(1 - 1 / scale),
+			newCenterPoint = map._getTopLeftPoint()._add(viewHalf)._add(centerOffset);
 
 		return map.unproject(newCenterPoint);
 	}
diff --git a/src/map/handler/Map.TouchZoom.js b/src/map/handler/Map.TouchZoom.js
index db9b4d13..b74c468c 100644
--- a/src/map/handler/Map.TouchZoom.js
+++ b/src/map/handler/Map.TouchZoom.js
@@ -24,7 +24,7 @@ L.Map.TouchZoom = L.Handler.extend({
 			p2 = map.mouseEventToLayerPoint(e.touches[1]),
 			viewCenter = map._getCenterLayerPoint();
 
-		this._startCenter = p1.add(p2).divideBy(2, true);
+		this._startCenter = p1._add(p2)._divideBy(2);
 		this._startDist = p1.distanceTo(p2);
 
 		this._moved = false;
@@ -48,7 +48,7 @@ L.Map.TouchZoom = L.Handler.extend({
 			p2 = map.mouseEventToLayerPoint(e.touches[1]);
 
 		this._scale = p1.distanceTo(p2) / this._startDist;
-		this._delta = p1.add(p2).divideBy(2, true).subtract(this._startCenter);
+		this._delta = p1._add(p2)._divideBy(2)._subtract(this._startCenter);
 
 		if (this._scale === 1) { return; }