const ParticleImageDisplayer = function(tag_id, canvas_el, params) {
"use strict";
this.pImageConfig = {
particles: {
array: [],
density: 100,
color: '#fff',
size: {
value: 2,
random: false,
},
movement: {
speed: 1,
restless: {
enabled: false,
value: 10,
sync: false
}
},
interactivity: {
on_hover: {
enabled: true,
action: 'repulse'
},
on_click: {
enabled: true,
action: 'big_repulse'
},
on_touch: {
enabled: false,
action: 'repulse'
},
fn_array: []
}
},
image: {
src: {
path: "https://raw.githubusercontent.com/paxtonfitzpatrick/particle-image/master/codepen-logo-demo.png",
is_external: true
},
size: {
canvas_pct: 60,
min_px: 100,
max_px: 800
}
},
interactions: {
repulse: {
distance: 100,
strength: 200
},
big_repulse: {
distance: 300,
strength: 250
},
grab: {
distance: 100,
line_width: 1,
}
},
canvas: {
el: canvas_el,
w: canvas_el.offsetWidth,
h: canvas_el.offsetHeight
},
functions: {
particles: {},
image: {},
canvas: {},
interactivity: {},
utils: {}
},
mouse: {
x: null,
y: null,
click_x: null,
click_y: null
},
};
const pImg = this.pImageConfig;
if (params) {
Object.deepExtend(pImg, params);
}
/*
========================================
= CANVAS FUNCTIONS =
========================================
*/
pImg.functions.canvas.init = function() {
pImg.canvas.context = pImg.canvas.el.getContext('2d');
pImg.canvas.el.width = pImg.canvas.w;
pImg.canvas.el.height = pImg.canvas.h;
pImg.canvas.aspect_ratio = pImg.canvas.w / pImg.canvas.h;
window.addEventListener('resize', pImg.functions.utils.debounce(pImg.functions.canvas.onResize, 200));
};
pImg.functions.canvas.onResize = function() {
pImg.canvas.w = pImg.canvas.el.offsetWidth;
pImg.canvas.h = pImg.canvas.el.offsetHeight;
pImg.canvas.el.width = pImg.canvas.w;
pImg.canvas.el.height = pImg.canvas.h;
pImg.canvas.aspect_ratio = pImg.canvas.w / pImg.canvas.h;
pImg.particles.array = [];
pImg.functions.image.resize();
const image_pixels = pImg.functions.canvas.getImagePixels();
pImg.functions.particles.createImageParticles(image_pixels, true);
};
pImg.functions.canvas.clear = function() {
pImg.canvas.context.clearRect(0, 0, pImg.canvas.w, pImg.canvas.h);
};
pImg.functions.canvas.getImagePixels = function() {
pImg.functions.canvas.clear();
pImg.canvas.context.drawImage(pImg.image.obj, pImg.image.x, pImg.image.y, pImg.image.obj.width, pImg.image.obj.height);
const pixel_data = pImg.canvas.context.getImageData(pImg.image.x, pImg.image.y, pImg.image.obj.width, pImg.image.obj.height);
pImg.functions.canvas.clear();
return pixel_data;
};
/*
========================================
= IMAGE FUNCTIONS =
========================================
*/
pImg.functions.image.resize = function() {
if (pImg.image.aspect_ratio < pImg.canvas.aspect_ratio) {
// canvas height constrains image size
pImg.image.obj.height = pImg.functions.utils.clamp(Math.round(pImg.canvas.h * pImg.image.size.canvas_pct / 100), pImg.image.size.min_px, pImg.image.size.max_px);
pImg.image.obj.width = Math.round(pImg.image.obj.height * pImg.image.aspect_ratio);
} else {
// canvas width constrains image size
pImg.image.obj.width = pImg.functions.utils.clamp(Math.round(pImg.canvas.w * pImg.image.size.canvas_pct / 100), pImg.image.size.min_px, pImg.image.size.max_px);
pImg.image.obj.height = Math.round(pImg.image.obj.width / pImg.image.aspect_ratio);
}
// set x,y coords to center image on canvas
pImg.image.x = pImg.canvas.w / 2 - pImg.image.obj.width / 2;
pImg.image.y = pImg.canvas.h / 2 - pImg.image.obj.height / 2;
};
pImg.functions.image.init = function() {
pImg.image.obj = new Image();
pImg.image.obj.addEventListener('load', function() {
// get aspect ratio (only have to compute once on initial load)
pImg.image.aspect_ratio = pImg.image.obj.width / pImg.image.obj.height;
pImg.functions.image.resize();
const img_pixels = pImg.functions.canvas.getImagePixels();
pImg.functions.particles.createImageParticles(img_pixels);
pImg.functions.particles.animateParticles();
});
pImg.image.obj.src = pImg.image.src.path;
if (pImg.image.src.is_external) {
pImg.image.obj.crossOrigin = "anonymous";
}
};
/*
========================================
= PARTICLE FUNCTIONS =
========================================
*/
pImg.functions.particles.SingleImageParticle = function(init_xy, dest_xy) {
this.x = init_xy.x;
this.y = init_xy.y;
this.dest_x = dest_xy.x;
this.dest_y = dest_xy.y;
this.vx = (Math.random() - 0.5) * pImg.particles.movement.speed;
this.vy = (Math.random() - 0.5) * pImg.particles.movement.speed;
this.acc_x = 0;
this.acc_y = 0;
this.friction = Math.random() * 0.01 + 0.92;
this.restlessness = {
max_displacement: Math.ceil(Math.random() * pImg.particles.movement.restless.value),
x_jitter: pImg.functions.utils.randIntInRange(-3, 3),
y_jitter: pImg.functions.utils.randIntInRange(-3, 3),
on_curr_frame: false
};
if (pImg.particles.color instanceof Array) {
this.color = pImg.particles.color[Math.floor(Math.random() * (pImg.particles.color.length + 1))];
} else {
this.color = pImg.particles.color;
}
this.radius = Math.round((pImg.particles.size.random ? Math.max(Math.random(), 0.5) : 1) * pImg.particles.size.value);
};
pImg.functions.particles.SingleImageParticle.prototype.draw = function() {
pImg.canvas.context.fillStyle = this.color;
pImg.canvas.context.beginPath();
pImg.canvas.context.arc(this.x, this.y, this.radius, 0, Math.PI * 2, false);
pImg.canvas.context.fill();
};
pImg.functions.particles.createImageParticles = function(pixel_data, at_dest = false) {
const increment = Math.round(pixel_data.width / pImg.particles.density);
for (let i = 0; i < pixel_data.width; i += increment) {
for (let j = 0; j < pixel_data.height; j += increment) {
if (pixel_data.data[(i + j * pixel_data.width) * 4 + 3] > 128) {
const dest_xy = {x: pImg.image.x + i, y: pImg.image.y + j};
const init_xy = at_dest ? dest_xy : {x: Math.random() * pImg.canvas.w, y: Math.random() * pImg.canvas.h};
pImg.particles.array.push(new pImg.functions.particles.SingleImageParticle(init_xy, dest_xy));
}
}
}
};
pImg.functions.particles.updateParticles = function() {
for (let p of pImg.particles.array) {
if ((pImg.particles.movement.restless.enabled) && (p.restlessness.on_curr_frame)) {
// if restless activity is enabled & particle is in restless mode, animate some random movement
pImg.functions.particles.jitterParticle(p);
} else {
// otherwise, update position with approach to destination
p.acc_x = (p.dest_x - p.x) / 500;
p.acc_y = (p.dest_y - p.y) / 500;
p.vx = (p.vx + p.acc_x) * p.friction;
p.vy = (p.vy + p.acc_y) * p.friction;
p.x += p.vx;
p.y += p.vy;
}
pImg.functions.interactivity.interactWithClient(p);
}
};
pImg.functions.particles.jitterParticle = function(p) {
p.x += p.restlessness.x_jitter;
p.y += p.restlessness.y_jitter;
if (Math.sqrt((p.dest_x - p.x) ** 2 + (p.dest_y - p.y) ** 2) >= pImg.particles.movement.restless.value) {
p.restlessness.on_curr_frame = false;
}
};
pImg.functions.particles.animateParticles = function() {
pImg.functions.canvas.clear()
pImg.functions.particles.updateParticles();
for (let p of pImg.particles.array) {
p.draw();
}
requestAnimFrame(pImg.functions.particles.animateParticles);
};
/*
========================================
= INTERACTIVITY FUNCTIONS =
========================================
*/
pImg.functions.interactivity.repulseParticle = function(p, args) {
// compute distance to mouse
const dx_mouse = p.x - pImg.mouse.x,
dy_mouse = p.y - pImg.mouse.y,
mouse_dist = Math.sqrt(dx_mouse * dx_mouse + dy_mouse * dy_mouse),
inv_strength = pImg.functions.utils.clamp(300 - args.strength, 10, 300);
if (mouse_dist <= args.distance) {
p.acc_x = (p.x - pImg.mouse.x) / inv_strength;
p.acc_y = (p.y - pImg.mouse.y) / inv_strength;
p.vx += p.acc_x;
p.vy += p.acc_y;
}
};
pImg.functions.interactivity.grabParticle = function(p, args) {
const dx_mouse = p.x - pImg.mouse.x,
dy_mouse = p.y - pImg.mouse.y,
mouse_dist = Math.sqrt(dx_mouse * dx_mouse + dy_mouse * dy_mouse);
if (mouse_dist <= args.distance) {
pImg.canvas.context.strokeStyle = p.color;
pImg.canvas.context.lineWidth = Math.min(args.line_width, p.radius * 2);
pImg.canvas.context.beginPath();
pImg.canvas.context.moveTo(p.x, p.y);
pImg.canvas.context.lineTo(pImg.mouse.x, pImg.mouse.y);
pImg.canvas.context.stroke();
pImg.canvas.context.closePath();
}
};
pImg.functions.interactivity.onMouseMove = function(func, args, p) {
if (pImg.mouse.x != null && pImg.mouse.y != null) {
func(p, args);
}
};
pImg.functions.interactivity.onMouseClick = function(func, args, p) {
if (pImg.mouse.click_x != null && pImg.mouse.click_y != null) {
func(p, args);
}
};
pImg.functions.interactivity.addEventListeners = function() {
if (pImg.particles.interactivity.on_hover.enabled || pImg.particles.interactivity.on_click.enabled) {
pImg.canvas.el.addEventListener('mousemove', function(e) {
let pos_x = e.offsetX || e.clientX,
pos_y = e.offsetY || e.clientY;
pImg.mouse.x = pos_x;
pImg.mouse.y = pos_y;
});
pImg.canvas.el.addEventListener('mouseleave', function(e) {
pImg.mouse.x = null;
pImg.mouse.y = null;
});
pImg.functions.utils.addEventActions('on_hover');
}
if (pImg.particles.interactivity.on_click.enabled) {
pImg.canvas.el.addEventListener('mousedown', function(e) {
pImg.mouse.click_x = pImg.mouse.x;
pImg.mouse.click_y = pImg.mouse.y;
});
pImg.canvas.el.addEventListener('mouseup', function(e) {
pImg.mouse.click_x = null;
pImg.mouse.click_y = null;
});
pImg.functions.utils.addEventActions('on_click');
}
if (pImg.particles.interactivity.on_touch.enabled) {
pImg.canvas.el.addEventListener('touchmove', function(e) {
let pos_x = e.touches[0].clientX,
pos_y = e.touches[0].clientY;
pImg.mouse.x = pos_x;
pImg.mouse.y = pos_y;
});
pImg.canvas.el.addEventListener('touchend', function(e) {
pImg.mouse.x = null;
pImg.mouse.y = null;
});
pImg.functions.utils.addEventActions('on_touch');
}
};
pImg.functions.interactivity.interactWithClient = function(p) {
for (let func of pImg.particles.interactivity.fn_array) {
func(p);
}
};
/*
========================================
= UTILS FUNCTIONS =
========================================
*/
pImg.functions.utils.randIntInRange = function(min, max) {
return Math.floor(Math.random() * (max - min + 1)) + min;
};
pImg.functions.utils.clamp = function(n, min, max) {
return Math.min(Math.max(n, min), max);
};
pImg.functions.utils.debounce = function(func, min_interval) {
let timer;
return function(event) {
if (timer) clearTimeout(timer);
timer = setTimeout(func, min_interval, event);
};
};
pImg.functions.utils.addEventActions = function(event) {
const action_funcs = {
repulse: pImg.functions.interactivity.repulseParticle,
big_repulse: pImg.functions.interactivity.repulseParticle,
grab: pImg.functions.interactivity.grabParticle
};
let event_wrapper = event === 'on_click' ? pImg.functions.interactivity.onMouseClick : pImg.functions.interactivity.onMouseMove;
if (pImg.particles.interactivity[event].enabled) {
const func = action_funcs[pImg.particles.interactivity[event].action],
args = pImg.interactions[pImg.particles.interactivity[event].action];
const partial_func = event_wrapper.bind(null, func, args);
pImg.particles.interactivity.fn_array.push(partial_func);
}
};
/*
========================================
= LAUNCH FUNCTIONS =
========================================
*/
pImg.functions.launch = function() {
pImg.functions.interactivity.addEventListeners();
pImg.functions.canvas.init();
pImg.functions.image.init();
};
if (!pImg.disabled) {
pImg.functions.launch();
}
};
/*
========================================
= GLOBAL FUNCTIONS =
========================================
*/
Object.deepExtend = function(destination, source) {
// credit: https://andrewdupont.net/2009/08/28/deep-extending-objects-in-javascript/
for (let property in source) {
if (source[property] && source[property].constructor &&
source[property].constructor === Object) {
destination[property] = destination[property] || {};
arguments.callee(destination[property], source[property]);
} else {
destination[property] = source[property];
}
}
return destination;
};
window.requestAnimFrame = (function() {
return window.requestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.mozRequestAnimationFrame ||
window.oRequestAnimationFrame ||
window.msRequestAnimationFrame ||
function(callback) {
window.setTimeout(callback, 1000 / 60);
};
})();
window.cancelRequestAnimFrame = (function() {
return window.cancelAnimationFrame ||
window.webkitCancelRequestAnimationFrame ||
window.mozCancelRequestAnimationFrame ||
window.oCancelRequestAnimationFrame ||
window.msCancelRequestAnimationFrame ||
clearTimeout
})();
window.pImgDom = [];
window.particleImageDisplay = function(tag_id) {
// get target element by ID, check for existing canvases
const pImage_el = document.getElementById(tag_id),
canvas_classname = 'particle-image-canvas-el',
existing_canvases = pImage_el.getElementsByClassName(canvas_classname);
// remove any existing canvases within div
if (existing_canvases.length) {
while(existing_canvases.length > 0){
pImage_el.removeChild(existing_canvases[0]);
}
}
// create canvas element, set size, append to target element
const canvas_el = document.createElement('canvas');
canvas_el.className = canvas_classname;
canvas_el.style.width = "100%";
canvas_el.style.height = "100%";
const canvas = document.getElementById(tag_id).appendChild(canvas_el);
if(canvas != null){
pImgDom.push(new ParticleImageDisplayer(tag_id, canvas, {}))
/*
NOTE: The this chunk normally deals with loading the params.json file. It's disabled for the CodePen demo so you can play with the parameters live by editing the pImageConfig object at the top.
// get params.json filepath from load parameters from element's data-params-src property
const params_json = pImage_el.dataset.paramsSrc,
xhr = new XMLHttpRequest();
xhr.overrideMimeType("application/json")
xhr.open("GET", params_json, false);
xhr.onreadystatechange = function() {
if (xhr.readyState === 4 && xhr.status === 200) {
// parse parameters & launch display
const params = JSON.parse(xhr.responseText);
pImgDom.push(new ParticleImageDisplayer(tag_id, canvas, params));
} else {
console.log(`failed to load params.json. XMLHTTPRequest status: ${xhr.statusText}`);
}
};
xhr.send();
*/
}
};
window.particleImageDisplay("particle-image");
!
