From a522f2bcdf8732af8e932ddfe32d09414b2e944c Mon Sep 17 00:00:00 2001
From: volterra79 <boccacci.francesco@gmail.com>
Date: Mon, 13 Feb 2023 14:18:50 +0100
Subject: [PATCH] Add cached property where store position, rotation and
 resolution. The las one property is used to avoid to reset initial starting
 rotation when resolution change due to zoom in zoom out of the map

---
 src/app/g3w-ol/controls/streetviewcontrol.js | 30 ++++++++++++++------
 1 file changed, 21 insertions(+), 9 deletions(-)

diff --git a/src/app/g3w-ol/controls/streetviewcontrol.js b/src/app/g3w-ol/controls/streetviewcontrol.js
index 89d82687a..ae893c05b 100644
--- a/src/app/g3w-ol/controls/streetviewcontrol.js
+++ b/src/app/g3w-ol/controls/streetviewcontrol.js
@@ -39,18 +39,30 @@ const StreetViewControl = function(options={}) {
   this._panorama = null;
   this._map = null;
   this._projection = null;
-  this._lastposition = null;
+  /**
+   * Object contain previuos data referred to :
+   * - rotation: for array rotation
+   * - resolution: map view resolution
+   * - position: lat lng of streetview
+   * @type {{rotation: null, position: null, resolution: null}}
+   */
+  this.cached = {
+    position: [0, 0],
+    resolution: null,
+    rotation: null
+  };
   this._streetViewFeature = new ol.Feature();
   const streetVectorSource = new ol.source.Vector({features: []});
   this.active = false;
   this._layer = new ol.layer.Vector({
     source: streetVectorSource,
-    style(feature) {
+    style: (feature, resolution) => {
       const coordinates = feature.getGeometry().getCoordinates();
-      this._lastposition = this._lastposition ? this._lastposition : coordinates;
-      const dx = coordinates[0] - this._lastposition[0];
-      const dy = coordinates[1] - this._lastposition[1];
-      const rotation = -Math.atan2(dy, dx);
+      if (null === this.cached.resolution || this.cached.resolution === resolution) {
+        const dx = coordinates[0] - this.cached.position[0];
+        const dy = coordinates[1] - this.cached.position[1];
+        this.cached.rotation = -Math.atan2(dy, dx);
+      }
       const styles = [
         new ol.style.Style({
           text: new ol.style.Text({
@@ -64,11 +76,12 @@ const StreetViewControl = function(options={}) {
         new ol.style.Style({
           image: new ol.style.Icon({
             src: '/static/client/images/streetviewarrow.png',
-            rotation
+            rotation: this.cached.rotation
           })
         })
       ];
-      this._lastposition = coordinates;
+      this.cached.position = coordinates;
+      this.cached.resolution = resolution;
       return styles
     }
   });
@@ -116,7 +129,6 @@ proto.setPosition = function(position) {
         pitch: 0,
         heading: 0
       });
-
       self._panorama.setPosition(data.location.latLng);
     }
   }).then(response => {