Add center arg to setAngle, center/offset to rotateTo, close #258

CHANGELOG.md

@@ -12,7 +12,7 @@ and `options` has `padding`, `offset`, `speed` and `curve` properties.
 - Changed `map.panTo` to accept `latlng[, options]` as arguments, where `options` has `duration`, `easing` and `offset` properties.
 - Changed `map.zoomTo` to accept `zoom[, options]` as arguments, where `options` has `duration`, `easing`,  `offset` and `center` properties.
 - Changed `map.scaleTo` to accept `scale[, options]` as arguments, where `options` has `duration`, `easing`, `offset` and `center` properties.
-- Changed `map.rotateTo` to accept `angle[, options]` as arguments, where `options` has `duration`, `easing` and `easing` properties.
+- Changed `map.rotateTo` to accept `angle[, options]` as arguments, where `options` has `duration`, `easing`, `offset` and `center` properties.
 - Changed `map.resetNorth` to accept optional `options` as argument, which has `duration` and `easing` properties.
 - Changed `map.zoomPanTo` to accept `latlng[, zoom, options]` as arguments,
 where `options` has `speed`, `curve` and `offset` properties.
@@ -24,6 +24,7 @@ where `options` has `speed`, `curve` and `offset` properties.
 they'll be calculated using the options above.
 - Zoom value used in styles now gets adjusted based on latitude. Disabled by `adjustZoom: false` in map options.
 Adjustment starts at 0% at zoom 6 and reaches 100% at zoom 9, configured by `minAdjustZoom` and `maxAdjustZoom` options.
+- Added `Map` `setAngle` second argument, `center`.
 - Improved `Map` `container` option to also be accepted as string (which is an element id) in addition to DOM element.
 - Added `LatLngBounds` geometry type.
 - Added `Map` `numWorkers` option (7 by default).

js/ui/easings.js

@@ -87,6 +87,8 @@ util.extend(exports, {
             center: mapCenter.add(offset)
         }, options);
 
+        options.center = Point.convert(options.center);
+
         var easing = this._updateEasing(options.duration, zoom, options.easing),
             startZoom = this.transform.zoom;
 
@@ -129,17 +131,21 @@ util.extend(exports, {
     rotateTo: function(angle, options) {
         this.stop();
 
+        var mapCenter = this.transform.centerPoint,
+            offset = Point.convert(options && options.offset || [0, 0]);
+
         options = util.extend({
             duration: 500,
-            easing: util.ease
+            easing: util.ease,
+            center: mapCenter.add(offset)
         }, options);
 
         var start = this.transform.angle;
         this.rotating = true;
 
         this._stopFn = util.timed(function(t) {
             if (t === 1) { this.rotating = false; }
-            this.setAngle(util.interp(start, angle, options.easing(t)));
+            this.setAngle(util.interp(start, angle, options.easing(t)), options.center);
         }, options.duration, this);
 
         return this;

js/ui/map.js

@@ -137,12 +137,22 @@ util.extend(Map.prototype, {
     },
 
     // Set the map's rotation given a center to rotate around and an angle in radians.
-    setAngle: function(angle) {
+    setAngle: function(angle, center) {
         // Confine the angle to within [-π,π]
         while (angle > Math.PI) angle -= Math.PI * 2;
         while (angle < -Math.PI) angle += Math.PI * 2;
 
+        center = Point.convert(center);
+        var origin = center && center.sub(this.transform.centerPoint);
+
+        if (center) {
+            this.transform.panBy(origin);
+        }
         this.transform.angle = angle;
+        if (center) {
+            this.transform.panBy(origin.mult(-1));
+        }
+
         this.update();
 
         return this