animateTo support reverse Rotation direction (#2414)

* animateTo support reverse  Rotation direction

* spec

* update spec

* updates

Author: deyihu

src/map/Map.Anim.ts

@@ -1,7 +1,7 @@
 import { Animation, Player } from '../core/Animation';
 import Coordinate from '../geo/Coordinate';
 import Point from '../geo/Point';
-import Map from './Map';
+import { Map, MapViewType } from './Map';
 import { isNil, isFunction, hasOwn, extend, clamp } from '../core/util';
 
 
@@ -36,6 +36,40 @@ declare module "./Map" {
 //     return true;
 // }
 
+function needValidateView(view: MapViewType, map: Map) {
+    const bearing = view.bearing;
+    const currentBearing = map.getBearing();
+    //当bearing溢出半角时,且线型变化时不经过0时,例如：[currentBearing=170,bearing=220],[currentBearing=-170,bearing=-220]
+    if (currentBearing >= 0 && bearing > 180) {
+        return false;
+    }
+    if (currentBearing <= 0 && bearing < -180) {
+        return false;
+    }
+    return true;
+}
+//反向旋转,bearing的变化正常为 [a,b],开启reverse后变化就反向了,例如 [170,-170] reverse后为 [170,190]
+function reverseBearing(view: MapViewType, map: Map) {
+    const bearing = view.bearing;
+    const currentBearing = map.getBearing();
+    //such as  [170,-170]
+    if (currentBearing >= 0 && bearing < 0) {
+        view.bearing = 180 + (180 - Math.abs(bearing));
+    }
+    //such as  [-170,170]
+    if (currentBearing <= 0 && bearing > 0) {
+        view.bearing = -180 - (180 - Math.abs(bearing));
+    }
+
+    if (currentBearing >= 0 && bearing > 0) {
+        view.bearing = -180 - (180 - Math.abs(bearing));
+    }
+
+    if (currentBearing <= 0 && bearing < 0) {
+        view.bearing = 180 + (180 - Math.abs(bearing));
+    }
+}
+
 Map.include(/** @lends Map.prototype */{
 
     /**
@@ -63,12 +97,18 @@ Map.include(/** @lends Map.prototype */{
      */
     animateTo(view, options = {}, step) {
         view = extend({}, this.getView(), view);
-        this._validateView(view);
+        view.bearing = view.bearing % 360;
         // this._stopAnim(this._animPlayer);
         if (isFunction(options)) {
             step = options;
             options = {};
         }
+        if ((options as any).counterclockwise) {
+            reverseBearing(view, this);
+        }
+        if (needValidateView(view, this)) {
+            this._validateView(view);
+        }
         const projection = this.getProjection(),
             currView = this.getView(),
             props = {};
@@ -228,7 +268,13 @@ Map.include(/** @lends Map.prototype */{
         // Where applicable, local variable documentation begins with the associated variable or
         // function in van Wijk (2003).
         view = extend({}, this.getView(), view);
-        this._validateView(view);
+        view.bearing = view.bearing % 360;
+        if ((options as any).counterclockwise) {
+            reverseBearing(view, this);
+        }
+        if (needValidateView(view, this)) {
+            this._validateView(view);
+        }
 
         if (this._animPlayer) {
             if (this._isInternalAnimation) {

src/map/Map.Camera.ts

@@ -354,8 +354,8 @@ Map.include(/** @lends Map.prototype */{
      */
     setCameraOrientation(params) {
         const { position } = params;
-        let { pitch, bearing } = params;
         this._validateView(params);
+        let { pitch, bearing } = params;
         pitch = pitch || 0;
         bearing = bearing || 0;
         const { zoom, cameraToGroundDistance } = this.getFitZoomForCamera(position, pitch);

src/map/Map.ts

@@ -1045,8 +1045,21 @@ export class Map extends Handlerable(Eventable(Renderable(Class))) {
             return;
         }
         if (isNumber(view.bearing)) {
-            view.bearing = Math.max(-180, view.bearing);
-            view.bearing = Math.min(180, view.bearing);
+            let bearing = view.bearing;
+            //周期性
+            bearing = bearing % 360;
+            //自动转换为负的值
+            if (bearing > 180) {
+                bearing = -180 + Math.abs(bearing - 180);
+            }
+            //自动转换为正的值
+            if (bearing < -180) {
+                bearing = 180 - Math.abs(bearing + 180);
+            }
+            view.bearing = bearing;
+
+            // view.bearing = Math.max(-180, view.bearing);
+            // view.bearing = Math.min(180, view.bearing);
         }
         if (isNumber(view.pitch)) {
             view.pitch = Math.max(0, view.pitch);
@@ -2829,7 +2842,7 @@ export type MapDataURLType = {
     save?: boolean;
 }
 
-export type MapAnimationOptionsType = AnimationOptionsType;
+export type MapAnimationOptionsType = AnimationOptionsType & { counterclockwise?: boolean }
 
 export type MapIdentifyOptionsType = {
     tolerance?: number;