calculate speed (test pull request)

src/components/Speedometer.tsx

@@ -9,6 +9,11 @@ interface IProps {}
 interface IState {
     gw2data_ipc: IGw2MumbleLinkData | null;
     gw2data_ws: IGw2MumbleLinkData | null;
+    now_position: any;
+    now_timestamp: any;
+    last_position: any;
+    last_timestamp: any;
+    speed: any;
 }
 
 const WS_CLIENT = "ws://localhost:19939/position";
@@ -18,7 +23,15 @@ class App extends React.Component<IProps, IState> {
     super(props);
     this.state = {
         gw2data_ipc: null,
-        gw2data_ws: null
+        gw2data_ws: null,
+
+        now_position: {x:0,y:0,z:0}, 
+        now_timestamp: 0,
+
+        last_position: {x:0,y:0,z:0},
+        last_timestamp: 0,
+
+        speed: 0,
     };
     this.gw2DataListener = this.gw2DataListener.bind(this);
       ipcRenderer.on('gw2data', this.gw2DataListener);      
@@ -30,9 +43,38 @@ class App extends React.Component<IProps, IState> {
         webSocket.onmessage = function (event) {
             var data = JSON.parse(event.data);
             self.setState({gw2data_ws: data});
+            if (self.state.last_timestamp + 10 < new Date().getTime()) {
+              // limit the calculation every 500 ms
+              self.calculateSpeed()
+            }
         }
+
   }
 
+  calculateSpeed() {
+
+    this.setState({now_position: this.state.gw2data_ws?.coordinates.playerPosition})
+    this.setState({now_timestamp: new Date().getTime()})
+    if (JSON.stringify(this.state.last_position) == JSON.stringify(this.state.now_position)) {
+      return
+    }
+
+
+    var a = this.state.last_position.X - this.state.now_position.X;
+    var b = this.state.last_position.Y - this.state.now_position.Y;
+    var c = this.state.last_position.Z - this.state.now_position.Z;
+
+    var distance = Math.sqrt(a * a + b * b + c * c);
+    var time = this.state.now_timestamp - this.state.last_timestamp
+
+    let speed = (distance * 39.3700787) / 0.01 ;
+    speed = Math.round((speed*100/10000)*99/72)
+
+    this.setState({speed: speed}) 
+    this.setState({last_position: this.state.now_position})
+    this.setState({last_timestamp: this.state.now_timestamp})
+  }
+
   componentWillUnmount() {
     ipcRenderer.removeAllListeners('gw2data');
   }
@@ -50,6 +92,9 @@ class App extends React.Component<IProps, IState> {
             <div>
             Coordinates (WS): {this.state.gw2data_ws?.coordinates.playerPosition.X} {this.state.gw2data_ws?.coordinates.playerPosition.Y} {this.state.gw2data_ws?.coordinates.playerPosition.Z}
             </div>
+            <div>
+            speed: {this.state.speed}
+            </div>
         </Window>
     );
   }