From 88f378bd5da7cf4ed35f01dd94ae67fdc4efd71c Mon Sep 17 00:00:00 2001
From: CodeDevMLH <malte@my-homeyer.de>
Date: Mon, 13 Jan 2025 01:16:37 +0100
Subject: [PATCH] switched to canvas

---
 snowfall.css   |  19 ++++--
 snowfall.js    | 153 ++++++++++++++++++++++++++++++++-----------------
 test-site.html |   2 +-
 3 files changed, 114 insertions(+), 60 deletions(-)

diff --git a/snowfall.css b/snowfall.css
index 4c0107b..9bf707b 100644
--- a/snowfall.css
+++ b/snowfall.css
@@ -1,8 +1,17 @@
-.snowflake {
+.snowfall-container {
     position: fixed;
-    background-color: white;
-    /* background-color: rgba(255, 255, 255, 0.8); */
-    border-radius: 50%;
+    width: 100%;
+    height: 100vh;
+    background: transparent;
+    overflow: hidden;
+    pointer-events: none;
+}
+
+#snowfallCanvas {
+    position: absolute;
+    top: 0;
+    left: 0;
+    width: 100%;
+    height: 100%;
     pointer-events: none;
-    /* opacity: 0.7; */
 }
\ No newline at end of file
diff --git a/snowfall.js b/snowfall.js
index c9c55b2..a531d9c 100644
--- a/snowfall.js
+++ b/snowfall.js
@@ -4,9 +4,11 @@ const snowFallSpeed = 3; // speed of snowfall	(recommended values: 0-5)
 
 let msgPrinted = false; // flag to prevent multiple console messages
 
+let canvas, ctx;  // canvas and context for drawing snowflakes
+
 // function to check and control the snowfall
 function toggleSnowfall() {
-  const snowfallContainer = document.querySelector('.snowfall');
+  const snowfallContainer = document.querySelector('.snowfall-container');
   if (!snowfallContainer) return;
 
   const videoPlayer = document.querySelector('.videoPlayerContainer');
@@ -41,66 +43,109 @@ observer.observe(document.body, {
 });
 
 
-function createSnowflakes() {
-  const container = document.querySelector('.snowfall') || document.createElement("div");
-
-  if (!document.querySelector('.snowfall')) {
-    container.className = "snowfall";
-    container.setAttribute("aria-hidden", "true");
-    document.body.appendChild(container);
+function initializeCanvas() {
+  const container = document.querySelector('.snowfall-container');
+  if (!container) {
+    console.error('Error: No element with class "snowfall-container" found.');
+    return;
   }
 
+  canvas = document.createElement('canvas');
+  canvas.id = 'snowfallCanvas';
+  container.appendChild(canvas);
+  ctx = canvas.getContext('2d');
 
-  const windowWidth = window.innerWidth;
-  const windowHeight = window.innerHeight;
-
-  for (let i = 0; i < snowflakesCount; i++) {
-    const snowflake = document.createElement('div');
-    snowflake.classList.add('snowflake');
-
-    // random size between 1 and 3 pixels
-    const size = Math.random() * 3 + 1;
-    snowflake.style.width = `${size}px`;
-    snowflake.style.height = `${size}px`;
-
-    // random starting position
-    snowflake.style.left = `${Math.random() * windowWidth}px`;
-    snowflake.style.top = `${Math.random() * windowHeight}px`;
-
-    container.appendChild(snowflake);
-
-    animateSnowflake(snowflake);
-  }
+  resizeCanvas(container);
+  window.addEventListener('resize', () => resizeCanvas(container));
 }
 
-function animateSnowflake(snowflake) {
-  // Animation Parameter
-  const speed = Math.random() * snowFallSpeed + 1;
-  // const speed = Math.random() * 3 + 1;
-  const sidewaysMovement = Math.random() * 2 - 1;
-
-  function fall() {
-      const currentTop = parseFloat(snowflake.style.top || 0);
-      const currentLeft = parseFloat(snowflake.style.left || 0);
-
-      // fall and sideways movement
-      snowflake.style.top = `${currentTop + speed}px`;
-      snowflake.style.left = `${currentLeft + sidewaysMovement}px`;
-
-      // if snowflake is out of the window, reset its position
-      if (currentTop > window.innerHeight) {
-          snowflake.style.top = '0px';
-          snowflake.style.left = `${Math.random() * window.innerWidth}px`;
-      }
-
-      requestAnimationFrame(fall);
-  }
-
-  fall();
+function resizeCanvas(container) {
+  const rect = container.getBoundingClientRect();
+  canvas.width = rect.width;
+  canvas.height = rect.height;
 }
 
+function createSnowflakes(container) {
+  return Array.from({ length: snowflakesCount }, () => ({
+    x: Math.random() * canvas.width,
+    y: Math.random() * canvas.height,
+    radius: Math.random() * 1.2 + 1,
+    speed: Math.random() * snowFallSpeed + 1,
+    swing: Math.random() * 2 - 1,
+  }));
+}
+
+// Initialize snowflakes
+let snowflakes = [];
+
+function drawSnowflakes() {
+  if (!ctx || !canvas) {
+    console.error('Error: Canvas or context not found.');
+    return;
+  }
+  ctx.clearRect(0, 0, canvas.width, canvas.height); // empty canvas
+
+  snowflakes.forEach(flake => {
+    ctx.beginPath();
+    ctx.arc(flake.x, flake.y, flake.radius, 0, Math.PI * 2);
+    ctx.fillStyle = 'white'; // color of snowflakes
+    ctx.fill();
+  });
+}
+
+function updateSnowflakes() {
+  snowflakes.forEach(flake => {
+    flake.y += flake.speed; // downwards movement
+    flake.x += flake.swing; // sideways movement
+
+    // reset snowflake if it reaches the bottom
+    if (flake.y > canvas.height) {
+      flake.y = 0;
+      flake.x = Math.random() * canvas.width; // with new random X position
+    }
+
+    // wrap snowflakes around the screen edges
+    if (flake.x > canvas.width) flake.x = 0;
+    if (flake.x < 0) flake.x = canvas.width;
+  });
+}
+
+function animateSnowfall() {
+  drawSnowflakes();
+  updateSnowflakes();
+  requestAnimationFrame(animateSnowfall);
+}
+
+
+/*
 // initialize snowfall after the DOM is loaded
 document.addEventListener('DOMContentLoaded', () => {
-  if (!snowfall) return; // exit if snowfall is disabled
-  createSnowflakes();
+  if (!snowfall){
+    console.warn('Snowfall is disabled.');
+    return; // exit if snowfall is disabled
+  }
+  const container = document.querySelector('.snowfall-container');
+  if (container) {
+    initializeCanvas();
+    snowflakes = createSnowflakes(container);
+    animateSnowfall();
+  }
 });
+*/
+
+// initialize snowfall
+function initializeSnowfall() {
+  if (!snowfall){
+    console.warn('Snowfall is disabled.');
+    return; // exit if snowfall is disabled
+  }
+  const container = document.querySelector('.snowfall-container');
+  if (container) {
+    console.log('Snowfall enabled.');
+    initializeCanvas();
+    snowflakes = createSnowflakes(container);
+    animateSnowfall();
+  }
+}
+
+initializeSnowfall();
\ No newline at end of file
diff --git a/test-site.html b/test-site.html
index 499ef44..a25aacc 100644
--- a/test-site.html
+++ b/test-site.html
@@ -15,7 +15,7 @@
 </head>
 
 <body>
-    <div class="snowfall"></div>
+    <div class="snowfall-container"></div>
     <script src="snowfall.js"></script>
 </body>