decentralized-id.github.io/assets/particle-banner/particles.js
2019-03-31 16:49:46 -04:00

151 lines
4.3 KiB
JavaScript

// Kass's Customizable Node/Particles Title
// settings:
const canvasName = "did-canvas"
const maxNodes = 40 // using too many will impact performance.
const nodeMinSize = 3
const nodeMaxSize = 4
const nodeMinSpeed = 0.02
const nodeMaxSpeed = 0.3
const nodeMaxConnections = 20
const connectionThickness = 2;
const connectionDist = 102
const connectionColor = "#0f477e"
const nodeColors = ['#0f477e'] // you may enter multiple colors ["#65c665", "#40a040"]
const warpEdges = false // if false nodes will bounce off the edges
const useIcon = false // if false then colored circles will be used
const iconPath = "https://image.flaticon.com/icons/png/128/137/137068.png"
const iconScale = 6
const useTrail = false
const backgroundColor = "#222222"
// another example can be found here https://codepen.io/cryptokass/pen/mgbajy?editors=0010
// canvas reference:
var canvas = document.getElementById(canvasName)
var ctx = canvas.getContext('2d')
// store canvas size:
let canvasHeight = +getComputedStyle(canvas).getPropertyValue("height").slice(0, -2);
let canvasWidth = +getComputedStyle(canvas).getPropertyValue("width").slice(0, -2);
canvas.height = canvasHeight
canvas.width = canvasWidth
// setup image
var img = new Image()
img.src = iconPath
// animation frame compatibility:
window.requestAnimFrame = function()
{
return (
window.requestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.mozRequestAnimationFrame ||
window.oRequestAnimationFrame ||
window.msRequestAnimationFrame ||
function(callback) { window.setTimeout(callback, 1000 / 60) }
);
}();
// node class
function Node(){
this.size = nodeMinSize + Math.random() * (nodeMaxSize-nodeMinSize)
this.x = canvasWidth * Math.random()
this.y = canvasHeight * Math.random()
this.color = nodeColors[Math.floor(Math.random()*nodeColors.length)]
this.connections = 0
// calculate starting velocity
let speed = nodeMinSpeed + Math.random() * (nodeMaxSpeed-nodeMinSpeed)
let theta = Math.random() * Math.PI * 2
this.velocity = {x:speed * Math.sin(theta), y:speed * Math.cos(theta)}
// move this node
this.move = function(){
if (this.x + this.velocity.x >= canvas.width || this.x + this.velocity.x <= 0){
if (warpEdges){
this.x = (this.x + this.velocity.x >= canvas.width ) ? 0 : canvas.width
} else {
this.velocity.x = -this.velocity.x
}
}
if (this.y + this.velocity.y >= canvas.height || this.y + this.velocity.y <= 0)
{
if (warpEdges) {
this.y = (this.y + this.velocity.y >= canvas.height ) ? 0 : canvas.height
} else {
this.velocity.y = -this.velocity.y
}
}
this.x += this.velocity.x
this.y += this.velocity.y
this.connections = 0
}
// draw this nodes connections
this.drawConnections = function(index){
for (let i=index+1; i < nodes.length; i++){
let node = nodes[i]
let dist = Math.sqrt(Math.pow(this.x - node.x,2) + Math.pow(this.y - node.y,2))
if (dist < connectionDist && node.connections < nodeMaxConnections && this.connections < nodeMaxConnections){
ctx.globalAlpha = 1-dist/connectionDist
ctx.beginPath()
ctx.moveTo(this.x,this.y)
ctx.lineTo(node.x, node.y)
ctx.lineWidth = connectionThickness
ctx.strokeStyle = connectionColor
ctx.stroke()
ctx.closePath()
node.connections++
this.connections++
}
}
}
this.draw = function(){
ctx.globalAlpha = 1
if (useIcon){
let _size = this.size * iconScale
let dx = this.x - _size/2
let dy = this.y - _size/2
ctx.drawImage(img, dx, dy, _size, _size)
}else{
ctx.beginPath()
ctx.arc(this.x, this.y, this.size, 0, Math.PI * 2)
ctx.fillStyle = this.color
ctx.fill()
ctx.closePath()
}
}
}
var nodes = []
for (let i=0; i < maxNodes; i++){
var node = new Node()
nodes.push(node)
}
function tick(){
if (useTrail){
ctx.globalAlpha = 0.1
ctx.rect(0,0,canvas.width, canvas.height)
ctx.fillStyle = backgroundColor
ctx.fill()
}else{
ctx.clearRect(0, 0, canvas.width, canvas.height)
}
for (let i=0; i < maxNodes; i++){
nodes[i].drawConnections(i)
}
for (let i=0; i < maxNodes; i++){
nodes[i].draw()
nodes[i].move()
}
requestAnimFrame(tick);
}
requestAnimFrame(tick);