turn down required speed

src/core/Void.js

@@ -41,7 +41,8 @@ class Void extends WebSocketEvents {
     this.maxClr = canvases[CANVAS_ID].colors.length;
     const area = TARGET_RADIUS ** 2 * Math.PI;
     const online = webSockets.onlineCounter;
-    const requiredSpeed = online * 4;
+    // require an average of 0.5 px / min / user
+    const requiredSpeed = Math.floor(online / 2);
     const ppm = Math.ceil(area / EVENT_DURATION_MIN + requiredSpeed);
     // timeout between pixels
     this.msTimeout = 60 * 1000 / ppm;