Improve multiplayer

shared/src/helper/calculate-view-area.ts

@@ -0,0 +1,22 @@
+import { vec2 } from 'gl-matrix';
+import { Rectangle, settings } from '../main';
+
+export const calculateViewArea = (
+  center: vec2,
+  aspectRatio: number,
+  oversizeRatio = 1,
+): Rectangle => {
+  const viewArea = new Rectangle();
+
+  viewArea.size = vec2.fromValues(
+    Math.sqrt(settings.inViewAreaSize * oversizeRatio * aspectRatio),
+    Math.sqrt((settings.inViewAreaSize * oversizeRatio) / aspectRatio),
+  );
+
+  viewArea.topLeft = vec2.fromValues(
+    center.x - viewArea.size.x / 2,
+    center.y + viewArea.size.y / 2,
+  );
+
+  return viewArea;
+};

shared/src/helper/circle.ts

@@ -9,6 +9,10 @@ export class Circle {
     return vec2.distance(this.center, target) - this.radius;
   }
 
+  public distanceBetween(target: Circle): number {
+    return vec2.distance(target.center, this.center) - this.radius - target.radius;
+  }
+
   public toArray(): Array<any> {
     return [this.center, this.radius];
   }