live - 60fps 1920 x 1080
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<title>Long Shadow</title>
<style>
html {
height: 100%;
}
body {
margin: 0;
padding: 0;
height: 100%;
overflow: hidden;
cursor: none;
}
#canvas {
background-color: #2c343f;
width: 100%;
height: 100%;
}
</style>
</head>
<body>
<canvas id="canvas"></canvas>
<script>
var c = document.getElementById("canvas");
var ctx = c.getContext("2d");
function resize() {
var box = c.getBoundingClientRect();
c.width = box.width;
c.height = box.height;
}
var light = {
x: 160,
y: 200,
};
var colors = ["#f5c156", "#e6616b", "#5cd3ad"];
function drawLight() {
ctx.beginPath();
ctx.arc(light.x, light.y, 1000, 0, 2 * Math.PI);
var gradient = ctx.createRadialGradient(
light.x,
light.y,
0,
light.x,
light.y,
1000
);
gradient.addColorStop(0, "#3b4654");
gradient.addColorStop(1, "#2c343f");
ctx.fillStyle = gradient;
ctx.fill();
ctx.beginPath();
ctx.arc(light.x, light.y, 20, 0, 2 * Math.PI);
gradient = ctx.createRadialGradient(
light.x,
light.y,
0,
light.x,
light.y,
5
);
gradient.addColorStop(0, "#fff");
gradient.addColorStop(1, "#3b4654");
ctx.fillStyle = gradient;
ctx.fill();
}
function Box() {
this.half_size = Math.floor(Math.random() * 50 + 1);
this.x = Math.floor(Math.random() * c.width + 1);
this.y = Math.floor(Math.random() * c.height + 1);
this.r = Math.random() * Math.PI;
this.shadow_length = 2000;
this.color = colors[Math.floor(Math.random() * colors.length)];
this.getDots = function () {
var full = (Math.PI * 2) / 4;
var p1 = {
x: this.x + this.half_size * Math.sin(this.r),
y: this.y + this.half_size * Math.cos(this.r),
};
var p2 = {
x: this.x + this.half_size * Math.sin(this.r + full),
y: this.y + this.half_size * Math.cos(this.r + full),
};
var p3 = {
x: this.x + this.half_size * Math.sin(this.r + full * 2),
y: this.y + this.half_size * Math.cos(this.r + full * 2),
};
var p4 = {
x: this.x + this.half_size * Math.sin(this.r + full * 3),
y: this.y + this.half_size * Math.cos(this.r + full * 3),
};
return { p1: p1, p2: p2, p3: p3, p4: p4 };
};
this.rotate = function () {
var speed = (60 - this.half_size) / 20;
this.r += speed * 0.002;
this.x += speed;
this.y += speed;
};
this.draw = function () {
var dots = this.getDots();
ctx.beginPath();
ctx.moveTo(dots.p1.x, dots.p1.y);
ctx.lineTo(dots.p2.x, dots.p2.y);
ctx.lineTo(dots.p3.x, dots.p3.y);
ctx.lineTo(dots.p4.x, dots.p4.y);
ctx.fillStyle = this.color;
ctx.fill();
if (this.y - this.half_size > c.height) {
this.y -= c.height + 100;
}
if (this.x - this.half_size > c.width) {
this.x -= c.width + 100;
}
};
this.drawShadow = function () {
var dots = this.getDots();
var angles = [];
var points = [];
for (var dot in dots) {
var angle = Math.atan2(
light.y - dots[dot].y,
light.x - dots[dot].x
);
var endX =
dots[dot].x + this.shadow_length * Math.sin(-angle - Math.PI / 2);
var endY =
dots[dot].y + this.shadow_length * Math.cos(-angle - Math.PI / 2);
angles.push(angle);
points.push({
endX: endX,
endY: endY,
startX: dots[dot].x,
startY: dots[dot].y,
});
}
for (var i = points.length - 1; i >= 0; i--) {
var n = i == 3 ? 0 : i + 1;
ctx.beginPath();
ctx.moveTo(points[i].startX, points[i].startY);
ctx.lineTo(points[n].startX, points[n].startY);
ctx.lineTo(points[n].endX, points[n].endY);
ctx.lineTo(points[i].endX, points[i].endY);
ctx.fillStyle = "#2c343f";
ctx.fill();
}
};
}
var boxes = [];
function draw() {
ctx.clearRect(0, 0, c.width, c.height);
drawLight();
for (var i = 0; i < boxes.length; i++) {
boxes[i].rotate();
boxes[i].drawShadow();
}
for (var i = 0; i < boxes.length; i++) {
collisionDetection(i);
boxes[i].draw();
}
requestAnimationFrame(draw);
}
resize();
draw();
while (boxes.length < 14) {
boxes.push(new Box());
}
window.onresize = resize;
c.onmousemove = function (e) {
light.x = e.offsetX === undefined ? e.layerX : e.offsetX;
light.y = e.offsetY === undefined ? e.layerY : e.offsetY;
};
function collisionDetection(b) {
for (var i = boxes.length - 1; i >= 0; i--) {
if (i != b) {
var dx =
boxes[b].x + boxes[b].half_size -
(boxes[i].x + boxes[i].half_size);
var dy =
boxes[b].y + boxes[b].half_size -
(boxes[i].y + boxes[i].half_size);
var d = Math.sqrt(dx * dx + dy * dy);
if (d < boxes[b].half_size + boxes[i].half_size) {
boxes[b].half_size = boxes[b].half_size > 1 ? boxes[b].half_size - 1 : 1;
boxes[i].half_size = boxes[i].half_size > 1 ? boxes[i].half_size - 1 : 1;
}
}
}
}
</script>
</body>
</html>About this animation
Dynamic long shadow effect generator for icons.
Under the hood
Dynamic Layered Text Shadows
This typography effect relies on sequentially stacking dozens of CSS
text-shadow properties offset by 1 pixel each. A CSS animation seamlessly alters the angle of the offsets to rotate the shadow in a full 360-degree circle. Related
