From ee29365824204d81597acb6d9b124072dda67c03 Mon Sep 17 00:00:00 2001
From: schmelczerandras <andras@schmelzer.dev>
Date: Thu, 1 Oct 2020 11:26:23 +0200
Subject: [PATCH] Optimize scene change

---
 src/index.ts                  | 20 +++++++++++++-------
 src/scenes/rain/rain-scene.ts |  1 +
 src/scenes/tunnel-scene.ts    |  1 +
 3 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/src/index.ts b/src/index.ts
index b29af4a..ab9ef54 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -42,10 +42,10 @@ const handleTextToggle = () => {
 toggleButton.addEventListener('click', handleTextToggle);
 handleTextToggle();
 
-const handleScene = async (SceneConstructor: new () => Scene) => {
-  const scene = new SceneConstructor();
-  await scene.initialize(canvas, overlay);
-
+const handleScene = async (
+  currentScene: Scene,
+  NextSceneConstructor: new () => Scene
+): Promise<Scene> => {
   let triggerIsOver: () => void;
   const isOver = new Promise((resolve) => (triggerIsOver = resolve));
   let timeSinceStart = 0;
@@ -53,7 +53,7 @@ const handleScene = async (SceneConstructor: new () => Scene) => {
   const handleFrame = (currentTime: DOMHighResTimeStamp) => {
     const deltaTime = deltaTimeCalculator.getNextDeltaTime(currentTime);
 
-    scene.drawNextFrame(currentTime, deltaTime);
+    currentScene.drawNextFrame(currentTime, deltaTime);
 
     if ((timeSinceStart += deltaTime) > sceneIntervalInSeconds * 1000) {
       triggerIsOver();
@@ -63,15 +63,21 @@ const handleScene = async (SceneConstructor: new () => Scene) => {
   };
 
   requestAnimationFrame(handleFrame);
+  const nextScene = new NextSceneConstructor();
+  await nextScene.initialize(canvas, overlay);
   await isOver;
-  scene.destroy();
+  currentScene.destroy();
+
+  return nextScene;
 };
 
 const main = async () => {
   try {
     let i = 0;
+    let currentScene: Scene = new scenes[i++]();
+    await currentScene.initialize(canvas, overlay);
     for (;;) {
-      await handleScene(scenes[i++ % scenes.length]);
+      currentScene = await handleScene(currentScene, scenes[i++ % scenes.length]);
     }
   } catch (e) {
     console.error(e);
diff --git a/src/scenes/rain/rain-scene.ts b/src/scenes/rain/rain-scene.ts
index 953d7f6..213cb0c 100644
--- a/src/scenes/rain/rain-scene.ts
+++ b/src/scenes/rain/rain-scene.ts
@@ -36,6 +36,7 @@ export class RainScene implements Scene {
       ambientLight: rgb(0.2, 0.2, 0.2),
       backgroundColor: rgb(1, 1, 1),
       colorPalette: [rgb(1, 1, 1), rgb(0.3, 1, 1), rgb(1, 1, 0), rgb(0.3, 1, 1)],
+      enableHighDpiRendering: false,
     });
 
     for (let i = 0; i < (canvas.getBoundingClientRect().width / 800) * 20; i++) {
diff --git a/src/scenes/tunnel-scene.ts b/src/scenes/tunnel-scene.ts
index 2883c7e..98e2709 100644
--- a/src/scenes/tunnel-scene.ts
+++ b/src/scenes/tunnel-scene.ts
@@ -81,6 +81,7 @@ export class TunnelScene implements Scene {
       ambientLight: rgb(0.35, 0.1, 0.45),
       backgroundColor: rgba(1, 1, 1, 1),
       colorPalette: [rgb(0.4, 0.5, 0.6), rgb(0, 0, 0), rgb(0, 0, 0), rgb(0, 0, 0)],
+      enableHighDpiRendering: false,
     });
 
     for (let i = 0; i < 200; i++) {