Merge pull request #1011 from redbirdly/main

Create clouds.js

mods/clouds.js

@@ -0,0 +1,80 @@
+// Clouds.js beta version
+
+// Biased random
+function randomGaussian(A, B, biasFactor=2) {
+    let u = Math.random();
+    let v = Math.random();
+    let num = Math.sqrt(-2.0 * Math.log(u)) * Math.cos(2.0 * Math.PI * v);
+
+    let mean = (A + B) / 2;
+    let stdDev = (B - A) / biasFactor;
+
+    let result = mean + num * stdDev;
+
+    return Math.min(Math.max(result, A), B);
+}
+
+// Spawn clouds
+var clouds = [];
+setTimeout(() => {
+	for (var i = 0;i < 50;i++) {
+		var w = (Math.random() * 13) + 7;
+		var h = (Math.random() * 9) + 4;
+
+		// Higher clouds = faster
+		var y = randomGaussian(0, height * 0.75, 5);
+		var speedFactor = (1 - (y / (height * 0.75)));
+
+		clouds.push({
+			x: Math.random() * (width - w),
+			y: y,
+			w: w,
+			h: h,
+			dx: ((Math.random() - 0.5) * 0.05) * (0.5 + speedFactor * 2),
+			type: Math.random() > 0.5 ? 1 : 0
+		});
+	}
+}, 200);
+
+function renderClouds(ctx) {
+	ctx.strokeStyle = "transparent";
+	ctx.globalAlpha = 1.0;
+
+	for (var i = 0;i < clouds.length;i++) {
+		var cloud = clouds[i];
+
+		var gradient = ctx.createLinearGradient(
+			cloud.x * pixelSize, cloud.y * pixelSize,
+			cloud.x * pixelSize, (cloud.y + cloud.h) * pixelSize
+		);
+
+		var cloudColor = cloud.type == 1 ? "255,255,255" : "220,220,210"
+		gradient.addColorStop(0, `RGBA(${cloudColor},0.1)`);
+		gradient.addColorStop(1, `RGBA(${cloudColor},0.2)`);
+
+		ctx.filter = "blur(1px)";
+		ctx.fillStyle = gradient;
+		ctx.fillRect(cloud.x * pixelSize, cloud.y * pixelSize, cloud.w * pixelSize, cloud.h * pixelSize);
+		ctx.filter = "none";
+	}
+}
+
+function updateClouds() {
+	if (paused) {return;}
+
+	for (var i = 0;i < clouds.length;i++) {
+		var cloud = clouds[i];
+
+		cloud.x += cloud.dx;
+
+		// Wrap around
+		if (cloud.x > width) {
+			cloud.x = -cloud.w;
+		} else if (cloud.x + cloud.w < 0) {
+			cloud.x = width;
+		}
+	}
+}
+
+renderPrePixel(renderClouds);
+runEveryTick(updateClouds);