diff --git a/externs/olx.js b/externs/olx.js
index cb22551f9d..4b84a867e5 100644
--- a/externs/olx.js
+++ b/externs/olx.js
@@ -415,7 +415,8 @@ olx.OverlayOptions.prototype.autoPanMargin;
  *     extent: (ol.Extent|undefined),
  *     axisOrientation: (string|undefined),
  *     global: (boolean|undefined),
- *     worldExtent: (ol.Extent|undefined)}}
+ *     worldExtent: (ol.Extent|undefined),
+ *     getPointResolution: (function(number, ol.Coordinate):number|undefined) }}
  * @api
  */
 olx.ProjectionOptions;
@@ -468,6 +469,13 @@ olx.ProjectionOptions.prototype.global;
  */
 olx.ProjectionOptions.prototype.worldExtent;
 
+/**
+* Function to determine resolution at a point.
+* @type {(function(number, ol.Coordinate):number|undefined)}
+* @api
+*/
+olx.ProjectionOptions.prototype.getPointResolution;
+
 
 /**
  * Object literal with config options for the view.
diff --git a/src/ol/proj/proj.js b/src/ol/proj/proj.js
index 33c9da0f15..440a428f84 100644
--- a/src/ol/proj/proj.js
+++ b/src/ol/proj/proj.js
@@ -121,6 +121,13 @@ ol.proj.Projection = function(options) {
    */
   this.global_ = goog.isDef(options.global) ? options.global : false;
 
+  /**
+  * @private
+  * @type {function(number, ol.Coordinate):number}
+  */
+  this.getPointResolutionFunc_ = goog.isDef(options.getPointResolution) ?
+      options.getPointResolution : this.getPointResolution_;
+
   /**
    * @private
    * @type {ol.tilegrid.TileGrid}
@@ -206,6 +213,16 @@ ol.proj.Projection.prototype.isGlobal = function() {
 };
 
 
+/**
+* Set if the projection is a global projection which spans the whole world
+* @param {boolean} global Whether the projection is global.
+* @api stable
+*/
+ol.proj.Projection.prototype.setGlobal = function(global) {
+  this.global_ = global;
+};
+
+
 /**
  * @return {ol.tilegrid.TileGrid} The default tile grid.
  */
@@ -244,16 +261,29 @@ ol.proj.Projection.prototype.setWorldExtent = function(worldExtent) {
 
 
 /**
- * Get the resolution of the point in degrees. For projections with degrees as
- * the unit this will simply return the provided resolution. For other
- * projections the point resolution is estimated by transforming the center
- * pixel to EPSG:4326, measuring its width and height on the normal sphere,
- * and taking the average of the width and height.
- * @param {number} resolution Resolution.
- * @param {ol.Coordinate} point Point.
- * @return {number} Point resolution.
- */
-ol.proj.Projection.prototype.getPointResolution = function(resolution, point) {
+* Set the getPointResolution function for this projection.
+* @param {function(number, ol.Coordinate):number} func Function
+* @api
+*/
+ol.proj.Projection.prototype.setGetPointResolution = function(func) {
+  this.getPointResolutionFunc_ = func;
+};
+
+
+/**
+* Default version.
+* Get the resolution of the point in degrees or distance units.
+* For projections with degrees as the unit this will simply return the
+* provided resolution. For other projections the point resolution is
+* estimated by transforming the 'point' pixel to EPSG:4326,
+* measuring its width and height on the normal sphere,
+* and taking the average of the width and height.
+* @param {number} resolution Nominal resolution in projection units.
+* @param {ol.Coordinate} point Point to find adjusted resolution at.
+* @return {number} Point resolution at point in projection units.
+* @private
+*/
+ol.proj.Projection.prototype.getPointResolution_ = function(resolution, point) {
   var units = this.getUnits();
   if (units == ol.proj.Units.DEGREES) {
     return resolution;
@@ -284,6 +314,26 @@ ol.proj.Projection.prototype.getPointResolution = function(resolution, point) {
 };
 
 
+/**
+ * Get the resolution of the point in degrees or distance units.
+ * For projections with degrees as the unit this will simply return the
+ * provided resolution. The default for other projections is to estimate
+ * the point resolution by transforming the 'point' pixel to EPSG:4326,
+ * measuring its width and height on the normal sphere,
+ * and taking the average of the width and height.
+ * An alternative implementation may be given when constructing a
+ * projection. For many local projections,
+ * such a custom function will return the resolution unchanged.
+ * @param {number} resolution Resolution in projection units.
+ * @param {ol.Coordinate} point Point.
+ * @return {number} Point resolution in projection units.
+ * @api
+ */
+ol.proj.Projection.prototype.getPointResolution = function(resolution, point) {
+  return this.getPointResolutionFunc_(resolution, point);
+};
+
+
 /**
  * @private
  * @type {Object.<string, ol.proj.Projection>}