13/03/2018
JS code for snowfall
//modified from https://codepen.io/ivanodintsov/pen/KVgwRG?editors=0010. Snow size, speed, and wind modified.
var canvas = document.getElementById('snow'),
ctx = canvas.getContext('2d'),
width = ctx.canvas.width = document.body.offsetWidth,
height = ctx.canvas.height = document.body.offsetHeight,
animFrame = window.requestAnimationFrame ||
window.mozRequestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.msRequestAnimationFrame,
snowflakes = [];
window.onresize = function() {
width = ctx.canvas.width = document.body.offsetWidth,
height = ctx.canvas.height = document.body.offsetHeight;
}
function update() {
for (var i = 0; i < snowflakes.length; i++) {
snowflakes[i].update();
}
}
function Snow() {
this.x = random(0, width);
this.y = random(-height, 0);
this.radius = random(0.75, 5.0);
this.speed = random(4, 2);
this.wind = random(-0.75, 0.25);
}
Snow.prototype.draw = function() {
ctx.beginPath();
ctx.arc(this.x, this.y, this.radius, 0, 2 * Math.PI);
ctx.fillStyle = ' ';
ctx.fill();
ctx.closePath();
}
Snow.prototype.update = function() {
this.y += this.speed;
this.x += this.wind;
if (this.y > ctx.canvas.height) {
this.y = 0;
this.x = random(0, width);
}
}
function createSnow(count) {
for (var i = 0; i < count; i++) {
snowflakes[i] = new Snow();
}
}
function draw() {
ctx.clearRect(0, 0, ctx.canvas.width, ctx.canvas.height);
for (var i = 0; i < snowflakes.length; i++) {
snowflakes[i].draw();
}
}
function loop() {
draw();
update();
animFrame(loop);
}
function random(min, max) {
var rand = (min + Math.random() * (max - min)).toFixed(1);
rand = Math.round(rand);
return rand;
}
createSnow(150);
loop();
//test for accessibility
axe.run(function(err, results) {
console.log(results.violations);
});
Snow on canvas...
