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Created July 24, 2012 19:26
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index.coffeescript
###
Text masked spring particles
Author: Kushagra Gour a.k.a. Chin Chang
###
# requestanimationframe polyfill
window.requestAnimFrame = (->
return window.requestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.mozRequestAnimationFrame ||
window.oRequestAnimationFrame ||
window.msRequestAnimationFrame ||
(callback) ->
window.setTimeout callback, 1000 / 60
)();
# variables
canvas = null
ctx = null
num_particles = 800
density = 8
min_distance = 70
text_array = []
display_list = []
last_time = null
spring_constant = 0.2
damping_constant = 0.08
colors = ['#184DF4', '#F49A03', '#E01730', '#00A415']
W = window.innerWidth
H = window.innerHeight
init = (e) ->
canvas = document.getElementById 'c'
ctx = canvas.getContext '2d'
canvas.width = W
canvas.height = H
canvas.addEventListener 'mousemove', onMouseMove
changeWord 'Koi Mundo'
# create particles
if text_array.length
for i in [0...num_particles]
display_list.push new Particle
getTextArray = (ox, oy, w, h) ->
text_array = []
data = ctx.getImageData(ox, oy, w, h).data
for i in [0...h] by density
for j in [0...w] by density
linear_index = (i * w + j) * 4
if data[linear_index + 3] isnt 0
text_array.push {x: j, y: i}
return text_array
onMouseMove = (e) ->
mx = e.offsetX || e.pageX
my = e.offsetY || e.pageY
for child in display_list
dx = child.x - mx
dy = child.y - my
d = Math.sqrt dx * dx + dy * dy
if d < min_distance
child.speed_x += dx * 0.05
child.speed_y += dy * 0.05
changeWord = (str) ->
# clear the canvas first
ctx.clearRect 0, 0, W, H
# draw the new text
ctx.fillStyle = "#000"
ctx.textBaseline = 'top'
ctx.textAlign = 'center'
ctx.font = "200px Arial"
ctx.fillText str, W/2, 0
# get the text points
text_array = getTextArray 0, 0, W, H
for child in display_list
child.reposition()
animate = ->
animationLoop()
requestAnimFrame animate
animationLoop = ->
if !last_time then last_time = (new Date).getTime()
current_time = (new Date).getTime()
dt = (current_time - last_time) / 1000
last_time = current_time
window.fps = 1 / dt
draw()
update()
draw = ->
ctx.fillStyle = "#111"
ctx.fillRect 0, 0, W, H
for child in display_list
continue if typeof child.draw isnt 'function'
ctx.save();
ctx.translate child.x, child.y unless isNaN child.x or isNaN child.y
ctx.scale child.scale_x, child.scale_y unless isNaN child.scale_x or isNaN child.scale_y
ctx.globalAlpha = child.alpha unless isNaN child.alpha
child.draw()
ctx.restore();
update = ->
# update particles
for child in display_list
child.update() if typeof child.update is 'function'
class Particle
constructor: (@radius = 1, @x = Math.random() * W, @y = Math.random() * H) ->
@speed_x = 10 - Math.random() * 20
@speed_y = 10 - Math.random() * 20
@color = "#ff0"
@alpha = 1
@reposition()
@reset()
draw: ->
#ctx.drawImage canvas2, 0, 0
ctx.fillStyle = @color
ctx.beginPath()
ctx.arc 4, 4, 4, 0, Math.PI*2, true
ctx.fill()
update: ->
acc_x = -spring_constant * (@x - @ox) - damping_constant * @speed_x
acc_y = -spring_constant * (@y - @oy) - damping_constant * @speed_y
@speed_x += acc_x
@speed_y += acc_y
@alpha -= 0.019
@scale_x += 0.06
@scale_y += 0.06
@x += @speed_x
@y += @speed_y
if @alpha <= 0
@reset()
reset: ->
@alpha = Math.random()
@scale_x = @scale_y = 0
@color = colors[~~(Math.random() * colors.length)]
reposition: ->
point = text_array[~~(Math.random() * text_array.length)]
@ox = @x = point.x + ~~(3 + Math.random() * 6)
@oy = @y = point.y + ~~(3 + Math.random() * 6)
init()
animate()
Raw
index.html
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Sppringgy jelly! &middot; CodePen</title>
<!--
Copyright (c) 2012 maxw3st, http://codepen.io/maxw3st
Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-->
<style>
body { margin: 0; }
span { position: absolute; top: 15px; left: 5px; color: white; }
</style>
<style>
#codepen-footer, #codepen-footer * {
-webkit-box-sizing: border-box !important;
-moz-box-sizing: border-box !important;
box-sizing: border-box !important;
}
#codepen-footer {
display: block !important;
position: fixed !important;
bottom: 0 !important;
left: 0 !important;
width: 100% !important;
padding: 0 10px !important;
margin: 0 !important;
height: 30px !important;
line-height: 30px !important;
font-size: 12px !important;
color: #eeeeee !important;
background-color: #505050 !important;
text-align: left !important;
background: -webkit-linear-gradient(top, #505050, #383838) !important;
background: -moz-linear-gradient(top, #505050, #383838) !important;
background: -ms-linear-gradient(top, #505050, #383838) !important;
background: -o-linear-gradient(top, #505050, #383838) !important;
border-top: 1px solid black !important;
border-bottom: 1px solid black !important;
border-radius: 0 !important;
border-image: none !important;
box-shadow: inset 0 1px 0 #6e6e6e, 0 2px 2px rgba(0, 0, 0, 0.4) !important;
z-index: 300 !important;
font-family: "Lucida Grande", "Lucida Sans Unicode", Tahoma, sans-serif !important;
letter-spacing: 0 !important;
word-spacing: normal !important;
word-spacing: 0 !important;
-webkit-transform: none !important;
-moz-transform: none !important;
-ms-transform: none !important;
-o-transform: none !important;
transform: none !important;
}
#codepen-footer a {
color: #a7a7a7 !important;
text-decoration: none !important;
text-shadow: none !important;
border: 0 !important;
}
#codepen-footer a:hover {
color: white !important;
}
</style>
<script>
// Kill alerts, confirmations and prompts
// window.alert = function(){}; we're going to allow alerts for now
window.confirm = function(){};
window.prompt = function(){};
window.open = function(){};
window.print = function(){};
</script>
</head>
<body>
<canvas id=c></canvas>
<span>Try disturbing the particles with mouse</span>
<script>
(function() {
/*
Text masked spring particles
Author: Kushagra Gour a.k.a. Chin Chang
*/
(function() {
var H, Particle, W, animate, animationLoop, canvas, changeWord, colors, ctx, damping_constant, density, display_list, draw, getTextArray, init, last_time, min_distance, num_particles, onMouseMove, spring_constant, text_array, update;
window.requestAnimFrame = (function() {
return window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || window.oRequestAnimationFrame || window.msRequestAnimationFrame || function(callback) {
return window.setTimeout(callback, 1000 / 60);
};
})();
canvas = null;
ctx = null;
num_particles = 800;
density = 8;
min_distance = 70;
text_array = [];
display_list = [];
last_time = null;
spring_constant = 0.2;
damping_constant = 0.08;
colors = ['#184DF4', '#F49A03', '#E01730', '#00A415'];
W = window.innerWidth;
H = window.innerHeight;
init = function(e) {
var i, _results;
canvas = document.getElementById('c');
ctx = canvas.getContext('2d');
canvas.width = W;
canvas.height = H;
canvas.addEventListener('mousemove', onMouseMove);
changeWord('Koi Mundo');
if (text_array.length) {
_results = [];
for (i = 0; 0 <= num_particles ? i < num_particles : i > num_particles; 0 <= num_particles ? i++ : i--) {
_results.push(display_list.push(new Particle));
}
return _results;
}
};
getTextArray = function(ox, oy, w, h) {
var data, i, j, linear_index;
text_array = [];
data = ctx.getImageData(ox, oy, w, h).data;
for (i = 0; 0 <= h ? i < h : i > h; i += density) {
for (j = 0; 0 <= w ? j < w : j > w; j += density) {
linear_index = (i * w + j) * 4;
if (data[linear_index + 3] !== 0) {
text_array.push({
x: j,
y: i
});
}
}
}
return text_array;
};
onMouseMove = function(e) {
var child, d, dx, dy, mx, my, _i, _len, _results;
mx = e.offsetX || e.pageX;
my = e.offsetY || e.pageY;
_results = [];
for (_i = 0, _len = display_list.length; _i < _len; _i++) {
child = display_list[_i];
dx = child.x - mx;
dy = child.y - my;
d = Math.sqrt(dx * dx + dy * dy);
if (d < min_distance) {
child.speed_x += dx * 0.05;
_results.push(child.speed_y += dy * 0.05);
} else {
_results.push(void 0);
}
}
return _results;
};
changeWord = function(str) {
var child, _i, _len, _results;
ctx.clearRect(0, 0, W, H);
ctx.fillStyle = "#000";
ctx.textBaseline = 'top';
ctx.textAlign = 'center';
ctx.font = "200px Arial";
ctx.fillText(str, W / 2, 0);
text_array = getTextArray(0, 0, W, H);
_results = [];
for (_i = 0, _len = display_list.length; _i < _len; _i++) {
child = display_list[_i];
_results.push(child.reposition());
}
return _results;
};
animate = function() {
animationLoop();
return requestAnimFrame(animate);
};
animationLoop = function() {
var current_time, dt;
if (!last_time) last_time = (new Date).getTime();
current_time = (new Date).getTime();
dt = (current_time - last_time) / 1000;
last_time = current_time;
window.fps = 1 / dt;
draw();
return update();
};
draw = function() {
var child, _i, _len, _results;
ctx.fillStyle = "#111";
ctx.fillRect(0, 0, W, H);
_results = [];
for (_i = 0, _len = display_list.length; _i < _len; _i++) {
child = display_list[_i];
if (typeof child.draw !== 'function') continue;
ctx.save();
if (!isNaN(child.x || isNaN(child.y))) ctx.translate(child.x, child.y);
if (!isNaN(child.scale_x || isNaN(child.scale_y))) {
ctx.scale(child.scale_x, child.scale_y);
}
if (!isNaN(child.alpha)) ctx.globalAlpha = child.alpha;
child.draw();
_results.push(ctx.restore());
}
return _results;
};
update = function() {
var child, _i, _len, _results;
_results = [];
for (_i = 0, _len = display_list.length; _i < _len; _i++) {
child = display_list[_i];
if (typeof child.update === 'function') {
_results.push(child.update());
} else {
_results.push(void 0);
}
}
return _results;
};
Particle = (function() {
function Particle(radius, x, y) {
this.radius = radius != null ? radius : 1;
this.x = x != null ? x : Math.random() * W;
this.y = y != null ? y : Math.random() * H;
this.speed_x = 10 - Math.random() * 20;
this.speed_y = 10 - Math.random() * 20;
this.color = "#ff0";
this.alpha = 1;
this.reposition();
this.reset();
}
Particle.prototype.draw = function() {
ctx.fillStyle = this.color;
ctx.beginPath();
ctx.arc(4, 4, 4, 0, Math.PI * 2, true);
return ctx.fill();
};
Particle.prototype.update = function() {
var acc_x, acc_y;
acc_x = -spring_constant * (this.x - this.ox) - damping_constant * this.speed_x;
acc_y = -spring_constant * (this.y - this.oy) - damping_constant * this.speed_y;
this.speed_x += acc_x;
this.speed_y += acc_y;
this.alpha -= 0.019;
this.scale_x += 0.06;
this.scale_y += 0.06;
this.x += this.speed_x;
this.y += this.speed_y;
if (this.alpha <= 0) return this.reset();
};
Particle.prototype.reset = function() {
this.alpha = Math.random();
this.scale_x = this.scale_y = 0;
return this.color = colors[~~(Math.random() * colors.length)];
};
Particle.prototype.reposition = function() {
var point;
point = text_array[~~(Math.random() * text_array.length)];
this.ox = this.x = point.x + ~~(3 + Math.random() * 6);
return this.oy = this.y = point.y + ~~(3 + Math.random() * 6);
};
return Particle;
})();
init();
animate();
}).call(this);
})();
</script>
<div id="codepen-footer">
<a style="color: #f73535 !important;" href="https://codepen.wufoo.com/forms/m7x3r3/def/field14=" onclick="window.open(this.href, null, 'height=517, width=680, toolbar=0, location=0, status=1, scrollbars=1, resizable=1'); return false">Report Abuse</a>
&nbsp;
<a href="/maxw3st/pen/nIJkh" target="_blank">Edit this Pen</a>
</div>
</body>
</html>
Raw
markup.html
<canvas id=c></canvas>
<span>Try disturbing the particles with mouse</span>
Raw
style.css
body { margin: 0; }
span { position: absolute; top: 15px; left: 5px; color: white; }
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