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pixbit/index.html

Created July 27, 2012 01:12
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Interactive HTML5 Canvas Text
Raw
index.html
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Interactive Canvas Text &middot; CodePen</title>
<!--
Copyright (c) 2012 Tim Holman, http://codepen.io/tholman
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:0px;}
</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>
<script src="http://codepen.io/javascripts/libs/prefixfree.min.js"></script>
</head>
<body>
<canvas id='canvas'></canvas>
<script src="http://codepen.io/javascripts/libs/modernizr.js"></script>
<script>
(function() {
function Banner(){
var keyword = "HEY";
var canvas;
var context;
var bgCanvas;
var bgContext;
var denseness = 10;
//Each particle/icon
var parts = [];
var mouse = {x:-100,y:-100};
var mouseOnScreen = false;
var itercount = 0;
var itertot = 40;
this.initialize = function(canvas_id){
canvas = document.getElementById(canvas_id);
context = canvas.getContext('2d');
canvas.width = window.innerWidth;
canvas.height = window.innerHeight;
bgCanvas = document.createElement('canvas');
bgContext = bgCanvas.getContext('2d');
bgCanvas.width = window.innerWidth;
bgCanvas.height = window.innerHeight;
canvas.addEventListener('mousemove', MouseMove, false);
canvas.addEventListener('mouseout', MouseOut, false);
start();
}
var start = function(){
bgContext.fillStyle = "#000000";
bgContext.font = '300px impact';
bgContext.fillText(keyword, 85, 275);
clear();
getCoords();
}
var getCoords = function(){
var imageData, pixel, height, width;
imageData = bgContext.getImageData(0, 0, canvas.width, canvas.height);
// quickly iterate over all pixels - leaving density gaps
for(height = 0; height < bgCanvas.height; height += denseness){
for(width = 0; width < bgCanvas.width; width += denseness){
pixel = imageData.data[((width + (height * bgCanvas.width)) * 4) - 1];
//Pixel is black from being drawn on.
if(pixel == 255) {
drawCircle(width, height);
}
}
}
setInterval( update, 40 );
}
var drawCircle = function(x, y){
var startx = (Math.random() * canvas.width);
var starty = (Math.random() * canvas.height);
var velx = (x - startx) / itertot;
var vely = (y - starty) / itertot;
parts.push(
{c: '#' + (Math.random() * 0x949494 + 0xaaaaaa | 0).toString(16),
x: x, //goal position
y: y,
x2: startx, //start position
y2: starty,
r: true, //Released (to fly free!)
v:{x:velx , y: vely}
}
)
}
var update = function(){
var i, dx, dy, sqrDist, scale;
itercount++;
clear();
for (i = 0; i < parts.length; i++){
//If the dot has been released
if (parts[i].r == true){
//Fly into infinity!!
parts[i].x2 += parts[i].v.x;
parts[i].y2 += parts[i].v.y;
//Perhaps I should check if they are out of screen... and kill them?
}
if (itercount == itertot){
parts[i].v = {x:(Math.random() * 6) * 2 - 6 , y:(Math.random() * 6) * 2 - 6};
parts[i].r = false;
}
//Look into using svg, so there is no mouse tracking.
//Find distance from mouse/draw!
dx = parts[i].x - mouse.x;
dy = parts[i].y - mouse.y;
sqrDist = Math.sqrt(dx*dx + dy*dy);
if (sqrDist < 20){
parts[i].r = true;
}
//Draw the circle
context.fillStyle = parts[i].c;
context.beginPath();
context.arc(parts[i].x2, parts[i].y2, 4 ,0 , Math.PI*2, true);
context.closePath();
context.fill();
}
}
var MouseMove = function(e) {
if (e.layerX || e.layerX == 0) {
//Reset particle positions
mouseOnScreen = true;
mouse.x = e.layerX - canvas.offsetLeft;
mouse.y = e.layerY - canvas.offsetTop;
}
}
var MouseOut = function(e) {
mouseOnScreen = false;
mouse.x = -100;
mouse.y = -100;
}
//Clear the on screen canvas
var clear = function(){
context.fillStyle = '#333';
context.beginPath();
context.rect(0, 0, canvas.width, canvas.height);
context.closePath();
context.fill();
}
}
var banner = new Banner();
banner.initialize("canvas");
})();
</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="/tholman/pen/lDLhk" target="_blank">Edit this Pen</a>
</div>
</body>
</html>
Raw
index.js
function Banner(){
var keyword = "HEY";
var canvas;
var context;
var bgCanvas;
var bgContext;
var denseness = 10;
//Each particle/icon
var parts = [];
var mouse = {x:-100,y:-100};
var mouseOnScreen = false;
var itercount = 0;
var itertot = 40;
this.initialize = function(canvas_id){
canvas = document.getElementById(canvas_id);
context = canvas.getContext('2d');
canvas.width = window.innerWidth;
canvas.height = window.innerHeight;
bgCanvas = document.createElement('canvas');
bgContext = bgCanvas.getContext('2d');
bgCanvas.width = window.innerWidth;
bgCanvas.height = window.innerHeight;
canvas.addEventListener('mousemove', MouseMove, false);
canvas.addEventListener('mouseout', MouseOut, false);
start();
}
var start = function(){
bgContext.fillStyle = "#000000";
bgContext.font = '300px impact';
bgContext.fillText(keyword, 85, 275);
clear();
getCoords();
}
var getCoords = function(){
var imageData, pixel, height, width;
imageData = bgContext.getImageData(0, 0, canvas.width, canvas.height);
// quickly iterate over all pixels - leaving density gaps
for(height = 0; height < bgCanvas.height; height += denseness){
for(width = 0; width < bgCanvas.width; width += denseness){
pixel = imageData.data[((width + (height * bgCanvas.width)) * 4) - 1];
//Pixel is black from being drawn on.
if(pixel == 255) {
drawCircle(width, height);
}
}
}
setInterval( update, 40 );
}
var drawCircle = function(x, y){
var startx = (Math.random() * canvas.width);
var starty = (Math.random() * canvas.height);
var velx = (x - startx) / itertot;
var vely = (y - starty) / itertot;
parts.push(
{c: '#' + (Math.random() * 0x949494 + 0xaaaaaa | 0).toString(16),
x: x, //goal position
y: y,
x2: startx, //start position
y2: starty,
r: true, //Released (to fly free!)
v:{x:velx , y: vely}
}
)
}
var update = function(){
var i, dx, dy, sqrDist, scale;
itercount++;
clear();
for (i = 0; i < parts.length; i++){
//If the dot has been released
if (parts[i].r == true){
//Fly into infinity!!
parts[i].x2 += parts[i].v.x;
parts[i].y2 += parts[i].v.y;
//Perhaps I should check if they are out of screen... and kill them?
}
if (itercount == itertot){
parts[i].v = {x:(Math.random() * 6) * 2 - 6 , y:(Math.random() * 6) * 2 - 6};
parts[i].r = false;
}
//Look into using svg, so there is no mouse tracking.
//Find distance from mouse/draw!
dx = parts[i].x - mouse.x;
dy = parts[i].y - mouse.y;
sqrDist = Math.sqrt(dx*dx + dy*dy);
if (sqrDist < 20){
parts[i].r = true;
}
//Draw the circle
context.fillStyle = parts[i].c;
context.beginPath();
context.arc(parts[i].x2, parts[i].y2, 4 ,0 , Math.PI*2, true);
context.closePath();
context.fill();
}
}
var MouseMove = function(e) {
if (e.layerX || e.layerX == 0) {
//Reset particle positions
mouseOnScreen = true;
mouse.x = e.layerX - canvas.offsetLeft;
mouse.y = e.layerY - canvas.offsetTop;
}
}
var MouseOut = function(e) {
mouseOnScreen = false;
mouse.x = -100;
mouse.y = -100;
}
//Clear the on screen canvas
var clear = function(){
context.fillStyle = '#333';
context.beginPath();
context.rect(0, 0, canvas.width, canvas.height);
context.closePath();
context.fill();
}
}
var banner = new Banner();
banner.initialize("canvas");
Raw
markup.html
<canvas id='canvas'></canvas>
Raw
style.css
body { margin:0px;}
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