209 lines
9.7 KiB
HTML
209 lines
9.7 KiB
HTML
|
<!DOCTYPE html>
|
||
|
<html>
|
||
|
<head>
|
||
|
<meta charset="utf-8">
|
||
|
<title>背景连线动画</title>
|
||
|
<style>
|
||
|
html,
|
||
|
body {
|
||
|
overflow: hidden;
|
||
|
background: #262b2e
|
||
|
}
|
||
|
#canvas {
|
||
|
z-index: 1;
|
||
|
}
|
||
|
</style>
|
||
|
</head>
|
||
|
<body>
|
||
|
<div id="wrapper">
|
||
|
<canvas id="canvas" width="1920px" height="1080px"></canvas>
|
||
|
</div>
|
||
|
<script>
|
||
|
// min and max radius, radius threshold and percentage of filled circles
|
||
|
var radMin = 10,
|
||
|
radMax = 80,
|
||
|
filledCircle = 30, //percentage of filled circles
|
||
|
concentricCircle = 60, //percentage of concentric circles
|
||
|
radThreshold = 25; //IFF special, over this radius concentric, otherwise filled
|
||
|
|
||
|
//min and max speed to move
|
||
|
var speedMin = 0.3,
|
||
|
speedMax = 0.6;
|
||
|
|
||
|
//max reachable opacity for every circle and blur effect
|
||
|
var maxOpacity = 0.6;
|
||
|
|
||
|
//default palette choice
|
||
|
var colors = ['52,168,83', '117,95,147', '199,108,23', '194,62,55', '0,172,212', '120,120,120'],
|
||
|
circleBorder = 10,
|
||
|
backgroundLine = colors[0];
|
||
|
var backgroundMlt = 0.85;
|
||
|
|
||
|
//min distance for links
|
||
|
var linkDist = Math.min(canvas.width, canvas.height) / 2.4,
|
||
|
lineBorder = 2.5;
|
||
|
|
||
|
//most importantly: number of overall circles and arrays containing them
|
||
|
var maxCircles = 8;
|
||
|
var points = [];
|
||
|
|
||
|
|
||
|
//experimental vars
|
||
|
var circleExp = 1,
|
||
|
circleExpMax = 1.003,
|
||
|
circleExpMin = 0.997,
|
||
|
circleExpSp = 0.00004,
|
||
|
circlePulse = false;
|
||
|
|
||
|
var ctxfr = null;
|
||
|
//circle class
|
||
|
function Circle(background) {
|
||
|
this.x = randRange(-canvas.width / 2, canvas.width / 2);
|
||
|
this.y = randRange(-canvas.height / 2, canvas.height / 2);
|
||
|
this.radius = hyperRange(radMin, radMax);
|
||
|
this.filled = this.radius < radThreshold ? (randint(0, 100) > filledCircle ? false : 'full') : (randint(0, 100) > concentricCircle ? false : 'concentric');
|
||
|
this.color = colors[randint(0, colors.length - 1)];
|
||
|
this.borderColor = colors[randint(0, colors.length - 1)];
|
||
|
this.opacity = 0.05;
|
||
|
this.speed = randRange(speedMin, speedMax); // * (radMin / this.radius);
|
||
|
this.speedAngle = Math.random() * 2 * Math.PI;
|
||
|
this.speedx = Math.cos(this.speedAngle) * this.speed;
|
||
|
this.speedy = Math.sin(this.speedAngle) * this.speed;
|
||
|
var spacex = Math.abs((this.x - (this.speedx < 0 ? -1 : 1) * (canvas.width / 2 + this.radius)) / this.speedx),
|
||
|
spacey = Math.abs((this.y - (this.speedy < 0 ? -1 : 1) * (canvas.height / 2 + this.radius)) / this.speedy);
|
||
|
|
||
|
this.ttl = Math.min(spacex, spacey);
|
||
|
}
|
||
|
|
||
|
Circle.prototype.init = function() {
|
||
|
Circle.call(this, this.background);
|
||
|
};
|
||
|
|
||
|
//support functions
|
||
|
//generate random int a<=x<=b
|
||
|
function randint(a, b) {
|
||
|
return Math.floor(Math.random() * (b - a + 1) + a);
|
||
|
}
|
||
|
//generate random float
|
||
|
function randRange(a, b) {
|
||
|
return Math.random() * (b - a) + a;
|
||
|
}
|
||
|
//generate random float more likely to be close to a
|
||
|
function hyperRange(a, b) {
|
||
|
return Math.random() * Math.random() * Math.random() * (b - a) + a;
|
||
|
}
|
||
|
|
||
|
//rendering function
|
||
|
function drawCircle(ctx, circle) {
|
||
|
//circle.radius *= circleExp;
|
||
|
var radius = circle.background ? circle.radius *= circleExp : circle.radius /= circleExp;
|
||
|
ctx.beginPath();
|
||
|
ctx.arc(circle.x, circle.y, radius * circleExp, 0, 2 * Math.PI, false);
|
||
|
ctx.lineWidth = Math.max(1, circleBorder * (radMin - circle.radius) / (radMin - radMax));
|
||
|
ctx.strokeStyle = ['rgba(', circle.borderColor, ',', circle.opacity, ')'].join('');
|
||
|
if (circle.filled === 'full') {
|
||
|
ctx.fillStyle = ['rgba(', circle.borderColor, ',', circle.opacity, ')'].join('');
|
||
|
ctx.fill();
|
||
|
ctx.lineWidth=0;
|
||
|
ctx.strokeStyle = ['rgba(', circle.borderColor, ',', 0, ')'].join('');
|
||
|
}
|
||
|
ctx.stroke();
|
||
|
if (circle.filled === 'concentric') {
|
||
|
ctx.beginPath();
|
||
|
ctx.arc(circle.x, circle.y, radius / 2, 0, 2 * Math.PI, false);
|
||
|
ctx.lineWidth = Math.max(1, circleBorder * (radMin - circle.radius) / (radMin - radMax));
|
||
|
ctx.strokeStyle = ['rgba(', circle.color, ',', circle.opacity, ')'].join('');
|
||
|
ctx.stroke();
|
||
|
}
|
||
|
circle.x += circle.speedx;
|
||
|
circle.y += circle.speedy;
|
||
|
if (circle.opacity < maxOpacity) circle.opacity += 0.01;
|
||
|
circle.ttl--;
|
||
|
}
|
||
|
|
||
|
//initializing function
|
||
|
function init() {
|
||
|
|
||
|
var canvas1 = document.getElementById('canvas');
|
||
|
canvas1.width = document.documentElement.clientWidth;
|
||
|
canvas1.height = document.documentElement.clientHeight;
|
||
|
ctxfr = document.getElementById('canvas').getContext('2d');
|
||
|
ctxfr.globalCompositeOperation = 'destination-over';
|
||
|
//populating the screen
|
||
|
for (var i = 0; i < maxCircles * 2; i++) points.push(new Circle(false));
|
||
|
|
||
|
window.requestAnimationFrame(draw);
|
||
|
}
|
||
|
|
||
|
//rendering function
|
||
|
function draw() {
|
||
|
if (circlePulse) {
|
||
|
if (circleExp < circleExpMin || circleExp > circleExpMax) circleExpSp *= -1;
|
||
|
circleExp += circleExpSp;
|
||
|
}
|
||
|
|
||
|
ctxfr.clearRect(0, 0, canvas.width, canvas.height); // clear canvas
|
||
|
ctxfr.save();
|
||
|
ctxfr.translate(canvas.width / 2, canvas.height / 2);
|
||
|
|
||
|
|
||
|
//function to render each single circle, its connections and to manage its out of boundaries replacement
|
||
|
function renderPoints(ctx, arr) {
|
||
|
for (var i = 0; i < arr.length; i++) {
|
||
|
var circle = arr[i];
|
||
|
//checking if out of boundaries
|
||
|
if (circle.ttl<0) {}
|
||
|
var xEscape = canvas.width / 2 + circle.radius,
|
||
|
yEscape = canvas.height / 2 + circle.radius;
|
||
|
if (circle.ttl < -20) arr[i].init(arr[i].background);
|
||
|
//if (Math.abs(circle.y) > yEscape || Math.abs(circle.x) > xEscape) arr[i].init(arr[i].background);
|
||
|
drawCircle(ctx, circle);
|
||
|
}
|
||
|
for (var i = 0; i < arr.length - 1; i++) {
|
||
|
for (var j = i + 1; j < arr.length; j++) {
|
||
|
var deltax = arr[i].x - arr[j].x;
|
||
|
var deltay = arr[i].y - arr[j].y;
|
||
|
var dist = Math.pow(Math.pow(deltax, 2) + Math.pow(deltay, 2), 0.5);
|
||
|
//if the circles are overlapping, no laser connecting them
|
||
|
if (dist <= arr[i].radius + arr[j].radius) continue;
|
||
|
//otherwise we connect them only if the dist is < linkDist
|
||
|
if (dist < linkDist) {
|
||
|
var xi = (arr[i].x < arr[j].x ? 1 : -1) * Math.abs(arr[i].radius * deltax / dist);
|
||
|
var yi = (arr[i].y < arr[j].y ? 1 : -1) * Math.abs(arr[i].radius * deltay / dist);
|
||
|
var xj = (arr[i].x < arr[j].x ? -1 : 1) * Math.abs(arr[j].radius * deltax / dist);
|
||
|
var yj = (arr[i].y < arr[j].y ? -1 : 1) * Math.abs(arr[j].radius * deltay / dist);
|
||
|
ctx.beginPath();
|
||
|
ctx.moveTo(arr[i].x + xi, arr[i].y + yi);
|
||
|
ctx.lineTo(arr[j].x + xj, arr[j].y + yj);
|
||
|
var samecolor = arr[i].color == arr[j].color;
|
||
|
ctx.strokeStyle = ["rgba(", arr[i].borderColor, ",", Math.min(arr[i].opacity, arr[j].opacity) * ((linkDist - dist) / linkDist), ")"].join("");
|
||
|
ctx.lineWidth = (arr[i].background ? lineBorder * backgroundMlt : lineBorder) * ((linkDist - dist) / linkDist); //*((linkDist-dist)/linkDist);
|
||
|
ctx.stroke();
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
var startTime = Date.now();
|
||
|
renderPoints(ctxfr, points);
|
||
|
|
||
|
deltaT = Date.now() - startTime;
|
||
|
ctxfr.restore();
|
||
|
|
||
|
window.requestAnimationFrame(draw);
|
||
|
}
|
||
|
|
||
|
init();
|
||
|
|
||
|
|
||
|
|
||
|
|
||
|
/*Credits and aknowledgements:
|
||
|
Original Idea and Design by Luca Luzzatti
|
||
|
|
||
|
Optimizing tips from Benjamin K?stner
|
||
|
General tips from Salvatore Previti*/
|
||
|
</script>
|
||
|
</body>
|
||
|
</html>
|