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<!-- <div class="trigger"></div> -->
<!-- <article> -->
<p>
<a href="#" class="underline title">Underline</a>
</p>
<p class="text">
<a href="#" class="underline">Testing descenders</a>
<br>
<a href="#" class="underline">to see g and y and p</a>
<br>
<a href="#" class="underline">with a nice underline</a>
<br>
<a href="#" class="underline">jump google quick yogurt</a>
<br>
<a href="#" class="underline">spanning multiple lines is still broken though...</a>
<br>
</p>
<!-- </article> -->
.underline {
position: relative;
}
.underline span {
pointer-events: none;
}
.underline canvas {
pointer-events: auto;
position: absolute;
top: 0;
left: 0;
/*background-color: rgba(222, 222, 222, 0.1);*/
/*z-index: -1;*/
-moz-user-select: none;
-khtml-user-select: none;
-webkit-user-select: none;
-o-user-select: none;
cursor: pointer;
}
body {
font-size: 24px;
line-height: 36px;
color: #212121;
margin: 0 auto;
width: 500px;
padding: 0;
-moz-osx-font-smoothing: grayscale;
-webkit-font-smoothing: antialiased;
-moz-osx-font-smoothing: grayscale;
text-rendering: optimizeLegibility;
}
a {
text-decoration: none;
color: #212121; }
p {
font-family: "EB Garamond";
margin-top: 24px; }
p.text a {
font-size: 48px;
line-height: 1.4em;
font-style: italic; }
p a.title {
font-size: 126px;
line-height: 1.4em; }
p em {
font-style: italic; }
p:empty {
margin-top: 0px; }
/* Universal Module Definition */
(function (root, factory) {
if (typeof define === 'function' && define.amd) {
// AMD. Register as a named AMD module.
define('baselineRatio', [], function () {
return (root.baselineRatio = factory());
});
} else if (typeof exports === 'object') {
// Node. Does not work with strict CommonJS, but
// only CommonJS-like enviroments that support module.exports,
// like Node.
module.exports = factory();
} else {
// Browser globals
root.baselineRatio = factory();
}
}(this, function () {
var baselineRatio = function(elem) {
// Get the baseline in the context of whatever element is passed in.
elem = elem || document.body;
// The container is a little defenseive.
var container = document.createElement('div');
container.style.display = "block";
container.style.position = "absolute";
container.style.bottom = "0";
container.style.right = "0";
container.style.width = "0px";
container.style.height = "0px";
container.style.margin = "0";
container.style.padding = "0";
container.style.visibility = "hidden";
container.style.overflow = "hidden";
// Intentionally unprotected style definition.
var small = document.createElement('span');
var large = document.createElement('span');
// Large numbers help improve accuracy.
small.style.fontSize = "0px";
large.style.fontSize = "2000px";
small.innerHTML = "X";
large.innerHTML = "X";
container.appendChild(small);
container.appendChild(large);
// Put the element in the DOM for a split second.
elem.appendChild(container);
var smalldims = small.getBoundingClientRect();
var largedims = large.getBoundingClientRect();
elem.removeChild(container);
// Calculate where the baseline was, percentage-wise.
var baselineposition = smalldims.top - largedims.top;
var height = largedims.height;
return 1 - (baselineposition / height);
}
return baselineRatio;
}));
/*!
* classie v1.0.1
* class helper functions
* from bonzo https://github.com/ded/bonzo
* MIT license
*
* classie.has( elem, 'my-class' ) -> true/false
* classie.add( elem, 'my-new-class' )
* classie.remove( elem, 'my-unwanted-class' )
* classie.toggle( elem, 'my-class' )
*/
/*jshint browser: true, strict: true, undef: true, unused: true */
/*global define: false, module: false */
( function( window ) {
'use strict';
// class helper functions from bonzo https://github.com/ded/bonzo
function classReg( className ) {
return new RegExp("(^|\\s+)" + className + "(\\s+|$)");
}
// classList support for class management
// altho to be fair, the api sucks because it won't accept multiple classes at once
var hasClass, addClass, removeClass;
if ( 'classList' in document.documentElement ) {
hasClass = function( elem, c ) {
return elem.classList.contains( c );
};
addClass = function( elem, c ) {
elem.classList.add( c );
};
removeClass = function( elem, c ) {
elem.classList.remove( c );
};
}
else {
hasClass = function( elem, c ) {
return classReg( c ).test( elem.className );
};
addClass = function( elem, c ) {
if ( !hasClass( elem, c ) ) {
elem.className = elem.className + ' ' + c;
}
};
removeClass = function( elem, c ) {
elem.className = elem.className.replace( classReg( c ), ' ' );
};
}
function toggleClass( elem, c ) {
var fn = hasClass( elem, c ) ? removeClass : addClass;
fn( elem, c );
}
var classie = {
// full names
hasClass: hasClass,
addClass: addClass,
removeClass: removeClass,
toggleClass: toggleClass,
// short names
has: hasClass,
add: addClass,
remove: removeClass,
toggle: toggleClass
};
// transport
if ( typeof define === 'function' && define.amd ) {
// AMD
define( classie );
} else if ( typeof exports === 'object' ) {
// CommonJS
module.exports = classie;
} else {
// browser global
window.classie = classie;
}
})( window );
function MultipleUnderline(element, underlineStyles, elementStyles) {
//ctor
this.element = element;
this.text = this.element.textContent;
this.underlineStyles = underlineStyles;
// this.elementStyles = getElementStyles(element);
this.elementStyles = elementStyles;
this.canvas = document.createElement("canvas");
this.ctx = this.canvas.getContext('2d');
this.ratio = window.devicePixelRatio;
this.canvas.width = this.elementStyles.width*this.ratio;
this.canvas.height = this.elementStyles.height*this.ratio;
// this.canvas.height = this.canvas.clientHeight + this.elementStyles.lineHeight;
this.canvas.style.left = this.elementStyles.canvasLeft + 'px';
this.element.appendChild(this.canvas);
this.canvas.style.width = this.elementStyles.width + 'px';
this.ctx.font = this.font = this.elementStyles.fontStyle + ' '
+ multiplyValue(this.elementStyles.fontSize, this.ratio) + ' '
+ this.elementStyles.fontFamily;
this.multipleRedrawActive = false;
if (is_chrome) {
// chrome floor the lineheight when it is not a whole number
// this.elementStyles.lineHeight = Math.floor(this.elementStyles.lineHeight * this.ratio);
this.elementStyles.lineHeight = this.elementStyles.lineHeight * this.ratio;
} else {
this.elementStyles.lineHeight = this.elementStyles.lineHeight * this.ratio;
}
// determine the text-underline-width / strokeWidth
var dotWidth = this.ctx.measureText('.')['width'];
if (this.underlineStyles['text-underline-width'] == "auto") {
// if set to auto, calculate the optimized width based on font
this.strokeWidth = dotWidth/12;
} else {
//if set to px value, todo: other unit such as em?
this.strokeWidth = this.underlineStyles['text-underline-width'];
//get number value
this.strokeWidth = parseFloat(this.strokeWidth)*this.ratio;
}
// determine the text-underline-position / underlinePosition
// text-underline-position in ratio, todo: default and user set position ratio
if (this.underlineStyles['text-underline-position'] == "auto") {
// if set to auto, calculate the optimized width based on font
this.underlinePosition = parseFloat(this.elementStyles.fontSize) * this.ratio
* ( 1 - this.elementStyles.baselinePositionRatio +
this.elementStyles.baselinePositionRatio * 0.4)
+ this.strokeWidth/2;
} else {
//if set to ratio value, todo: other unit such as em, px?
var userUnderlinePosition = parseFloat(this.underlineStyles['text-underline-position']);
// console.log(userUnderlinePosition);
this.underlinePosition = parseFloat(this.elementStyles.fontSize) * this.ratio *
( 1 - this.elementStyles.baselinePositionRatio +
this.elementStyles.baselinePositionRatio * userUnderlinePosition)
+ this.strokeWidth/2;
}
var adjustValue = optimalStrokeWidthPos(this.strokeWidth, this.underlinePosition);
this.strokeWidth = adjustValue.strokeWidth;
this.underlinePosition = adjustValue.posY;
this.lines = [];
this.myStrings = [];
var words = this.text.match(/[^\s-]+-?\s?/g);
var line = '';
var linePositionY = 0;
var firstLineCount = 0;
for (var n = 0; n < words.length; n++) {
// add the whitespace after getting the width measurement
if (words[n].match(/\s+$/)) {
// the last character of words[n] is whitespace
var newWord = words[n].replace(/\s+$/, '');
var testLine = line + newWord;
var testLineMetrics = this.ctx.measureText(testLine);
var testLineWidth = testLineMetrics.width;
testLine = testLine + ' ';
} else {
var testLine = line + words[n];
var testLineMetrics = this.ctx.measureText(testLine);
var testLineWidth = testLineMetrics.width;
}
if (!firstLineCount) {
//the first line, should consider startingPointX
if (testLineWidth + this.elementStyles.textIndent * this.ratio > this.elementStyles.parentWidth * this.ratio && n > 0) {
// draw the underline
if (line.match(/\s+$/)) {
// the last character of line is whitespace
var lineMetrics = this.ctx.measureText(line.replace(/\s+$/, ''));
var lineWidth = lineMetrics.width;
} else {
var lineMetrics = this.ctx.measureText(line);
var lineWidth = lineMetrics.width;
}
var tempLine = {
lineText: line,
lineTextIndent: this.elementStyles.textIndent * this.ratio - 0.2,
linePositionY: linePositionY,
lineMeasureWidth: lineWidth
}
this.lines.push(tempLine)
line = words[n];
linePositionY += this.elementStyles.lineHeight;
firstLineCount++;
} else {
line = testLine;
}
} else {
if (testLineWidth > this.elementStyles.parentWidth * this.ratio && n > 0) {
// draw the underline
if (line.match(/\s+$/)) {
// the last character of line is whitespace
var lineMetrics = this.ctx.measureText(line.replace(/\s+$/, ''));
var lineWidth = lineMetrics.width;
} else {
var lineMetrics = this.ctx.measureText(line);
var lineWidth = lineMetrics.width;
}
var tempLine = {
lineText: line,
lineTextIndent: -0.2,
linePositionY: linePositionY,
lineMeasureWidth: lineWidth
}
this.lines.push(tempLine);
line = words[n];
linePositionY += this.elementStyles.lineHeight;
} else {
line = testLine;
}
}
}
// draw the last line
// draw the underline
if (line.match(/\s+$/)) {
// the last character of line is whitespace
var lineMetrics = this.ctx.measureText(line.replace(/\s+$/, ''));
var lineWidth = lineMetrics.width;
} else {
var lineMetrics = this.ctx.measureText(line);
var lineWidth = lineMetrics.width;
}
var tempLine = {
lineText: line,
lineTextIndent: -0.2,
linePositionY: linePositionY,
lineMeasureWidth: lineWidth
}
this.lines.push(tempLine);
for(var i = 0; i < this.lines.length; i++) {
var tempLine = this.lines[i];
var myString = new GuitarString(
this.ctx,
new Point(tempLine.lineTextIndent, tempLine.linePositionY + this.underlinePosition),
new Point(tempLine.lineTextIndent + tempLine.lineMeasureWidth, tempLine.linePositionY + this.underlinePosition),
this.strokeWidth, this.underlineStyles['text-underline-color'], this.ratio);
this.myStrings.push(myString);
}
this.drawUnderline();
this.drawHoles();
}
MultipleUnderline.prototype.drawUnderline = function(){
// draw the underline
for(var i = 0; i < this.myStrings.length; i++) {
var tempString = this.myStrings[i];
// tempString.clear();
tempString.update();
tempString.draw();
}
};
MultipleUnderline.prototype.drawHoles = function(){
// draw the font stroke
for(var i = 0; i < this.lines.length; i++) {
var tempLine = this.lines[i];
this.ctx.globalCompositeOperation = "destination-out";
this.ctx.font = this.font;
this.ctx.fillStyle = 'green';
this.ctx.textBaseline = 'top';
this.ctx.fillText(tempLine.lineText, tempLine.lineTextIndent, tempLine.linePositionY);
this.ctx.lineWidth = 2*this.ratio + this.strokeWidth*3.6;
this.ctx.strokeStyle = 'blue';
this.ctx.strokeText(tempLine.lineText, tempLine.lineTextIndent, tempLine.linePositionY);
}
}
MultipleUnderline.prototype.clear = function(){
// clear
var lastMultipleRedrawActive = this.multipleRedrawActive;
this.multipleRedrawActive = false;
for(var i = 0; i < this.myStrings.length; i++) {
var tempString = this.myStrings[i];
// this.myString.clear();
// console.log(tempString.redrawActive);
if(tempString.redrawActive) {
this.multipleRedrawActive = true;
}
}
// console.log(this.multipleRedrawActive);
if (this.multipleRedrawActive) {
console.log('clear now!')
this.ctx.clearRect(0, 0, this.canvas.width, this.canvas.height);
}
// if (!lastMultipleRedrawActive && this.multipleRedrawActive) {
// for(var i = 0; i < this.myStrings.length; i++) {
// var tempString = this.myStrings[i];
// tempString.drawLine();
// }
// }
};
MultipleUnderline.prototype.update = function(){
//update
};
MultipleUnderline.prototype.draw = function(){
// draw
if (this.multipleRedrawActive) {
this.drawUnderline();
this.drawHoles();
}
};
function MultipleUnderline(element, underlineStyles, elementStyles) {
//ctor
this.element = element;
this.text = this.element.textContent;
this.underlineStyles = underlineStyles;
// this.elementStyles = getElementStyles(element);
this.elementStyles = elementStyles;
this.canvas = document.createElement("canvas");
this.canvas.width = this.elementStyles.width;
this.canvas.height = this.elementStyles.height;
this.canvas.style.left = this.elementStyles.canvasLeft + 'px';
this.element.appendChild(this.canvas);
this.canvas.width = this.canvas.clientWidth;
this.canvas.height = this.canvas.clientHeight + this.elementStyles.lineHeight;
this.ctx = this.canvas.getContext('2d');
this.ctx.font = this.font = this.elementStyles.fontStyle + ' ' + this.elementStyles.fontSize + ' ' + this.elementStyles.fontFamily;
this.multipleRedrawActive = false;
if (is_chrome) {
// chrome floor the lineheight when it is not a whole number
this.elementStyles.lineHeight = Math.floor(this.elementStyles.lineHeight);
}
// determine the text-underline-width / strokeWidth
this.dotWidth = this.ctx.measureText('.')['width'];
if (this.underlineStyles['text-underline-width'] == "auto") {
// if set to auto, calculate the optimized width based on font
if (this.dotWidth / 6 <= 2) {
this.strokeWidth = Math.round(this.dotWidth / 3) / 2;
} else {
this.strokeWidth = Math.round(this.dotWidth / 6);
}
} else {
//if set to px value
this.strokeWidth = this.underlineStyles['text-underline-width'];
//get number value
this.strokeWidth = parseFloat(this.strokeWidth);
}
// determine the text-underline-position / underlinePosition
// text-underline-position in ratio
this.underlinePosition = parseFloat(this.elementStyles.fontSize) * 0.89;
if (this.strokeWidth <= 1 || (this.strokeWidth % 2 && this.strokeWidth > 2)) {
this.underlinePosition = Math.round(this.underlinePosition - 0.5) + 0.5;
} else {
this.underlinePosition = Math.round(this.underlinePosition);
}
this.lines = [];
this.myStrings = [];
var words = this.text.match(/[^\s-]+-?\s?/g);
var line = '';
var linePositionY = 0;
var firstLineCount = 0;
for (var n = 0; n < words.length; n++) {
// add the whitespace after getting the width measurement
if (words[n].match(/\s+$/)) {
// the last character of words[n] is whitespace
var newWord = words[n].replace(/\s+$/, '');
var testLine = line + newWord;
var testLineMetrics = this.ctx.measureText(testLine);
var testLineWidth = testLineMetrics.width;
testLine = testLine + ' ';
} else {
var testLine = line + words[n];
var testLineMetrics = this.ctx.measureText(testLine);
var testLineWidth = testLineMetrics.width;
}
if (!firstLineCount) {
//the first line, should consider startingPointX
if (testLineWidth + this.elementStyles.textIndent > this.elementStyles.parentWidth && n > 0) {
// draw the underline
if (line.match(/\s+$/)) {
// the last character of line is whitespace
var lineMetrics = this.ctx.measureText(line.replace(/\s+$/, ''));
var lineWidth = lineMetrics.width;
} else {
var lineMetrics = this.ctx.measureText(line);
var lineWidth = lineMetrics.width;
}
var tempLine = {
lineText: line,
lineTextIndent: this.elementStyles.textIndent,
linePositionY: linePositionY,
lineMeasureWidth: lineWidth
}
this.lines.push(tempLine)
line = words[n];
linePositionY += this.elementStyles.lineHeight;
firstLineCount++;
} else {
line = testLine;
}
} else {
if (testLineWidth > this.elementStyles.parentWidth && n > 0) {
// draw the underline
if (line.match(/\s+$/)) {
// the last character of line is whitespace
var lineMetrics = this.ctx.measureText(line.replace(/\s+$/, ''));
var lineWidth = lineMetrics.width;
} else {
var lineMetrics = this.ctx.measureText(line);
var lineWidth = lineMetrics.width;
}
var tempLine = {
lineText: line,
lineTextIndent: 0,
linePositionY: linePositionY,
lineMeasureWidth: lineWidth
}
this.lines.push(tempLine);
line = words[n];
linePositionY += this.elementStyles.lineHeight;
} else {
line = testLine;
}
}
}
// draw the last line
// draw the underline
if (line.match(/\s+$/)) {
// the last character of line is whitespace
var lineMetrics = this.ctx.measureText(line.replace(/\s+$/, ''));
var lineWidth = lineMetrics.width;
} else {
var lineMetrics = this.ctx.measureText(line);
var lineWidth = lineMetrics.width;
}
var tempLine = {
lineText: line,
lineTextIndent: 0,
linePositionY: linePositionY,
lineMeasureWidth: lineWidth
}
this.lines.push(tempLine);
for(var i = 0; i < this.lines.length; i++) {
var tempLine = this.lines[i];
var myString = new GuitarString(
this.ctx,
new Point(tempLine.lineTextIndent, tempLine.linePositionY + this.underlinePosition),
new Point(tempLine.lineTextIndent + tempLine.lineMeasureWidth, tempLine.linePositionY + this.underlinePosition),
this.strokeWidth, this.underlineStyles['text-underline-color'], 1);
this.myStrings.push(myString);
}
this.drawUnderline();
this.drawHoles();
}
MultipleUnderline.prototype.clear = function(){
// clear
var lastMultipleRedrawActive = this.multipleRedrawActive;
this.multipleRedrawActive = false;
for(var i = 0; i < this.myStrings.length; i++) {
var tempString = this.myStrings[i];
// this.myString.clear();
// console.log(tempString.redrawActive);
if(tempString.redrawActive) {
this.multipleRedrawActive = true;
}
}
// console.log(this.multipleRedrawActive);
if (this.multipleRedrawActive) {
console.log('clear now!')
this.ctx.clearRect(0, 0, this.canvas.width, this.canvas.height);
}
// if (!lastMultipleRedrawActive && this.multipleRedrawActive) {
// for(var i = 0; i < this.myStrings.length; i++) {
// var tempString = this.myStrings[i];
// tempString.drawLine();
// }
// }
};
MultipleUnderline.prototype.update = function(){
//update
};
MultipleUnderline.prototype.draw = function(){
// draw
if (this.multipleRedrawActive) {
this.drawUnderline();
this.drawHoles();
}
};
MultipleUnderline.prototype.drawUnderline = function(){
// draw the underline
for(var i = 0; i < this.myStrings.length; i++) {
var tempString = this.myStrings[i];
// tempString.clear();
tempString.update();
tempString.draw();
}
};
MultipleUnderline.prototype.drawHoles = function(){
// draw the font stroke
for(var i = 0; i < this.lines.length; i++) {
var tempLine = this.lines[i];
this.ctx.globalCompositeOperation = "destination-out";
this.ctx.font = this.font;
this.ctx.fillStyle = 'green';
this.ctx.textBaseline = 'top';
this.ctx.fillText(tempLine.lineText, tempLine.lineTextIndent, tempLine.linePositionY);
this.ctx.lineWidth = 3 + this.strokeWidth;
this.ctx.strokeStyle = 'blue';
this.ctx.strokeText(tempLine.lineText, tempLine.lineTextIndent, tempLine.linePositionY);
}
}
var multiplyValue = function(value, multiplier){
var str = value;
var m = multiplier;
var result = str.match(/(\d*\.?\d*)(.*)/);
//http://stackoverflow.com/questions/2868947/split1px-into-1px-1-px-in-javascript
return result[1] * m + result[2];
}
var optimalStrokeWidthPos = function(strokeWidth, posY){
if ( strokeWidth < 1) {
posY = Math.round(posY - 0.5) + 0.5;
} else if ( strokeWidth >= 1 ) {
strokeWidth = Math.round( strokeWidth );
if ( strokeWidth % 2 ){
// odd, posY -> 0.5
posY = Math.round(posY - 0.5) + 0.5;
} else {
// even, posY -> 1
posY = Math.round(posY);
}
}
return {
strokeWidth: strokeWidth,
posY: posY
}
}
function SingleUnderline(element, underlineStyles, elementStyles) {
//ctor
this.element = element;
this.text = this.element.textContent;
this.underlineStyles = underlineStyles;
this.elementStyles = elementStyles;
this.redrawActive = false;
this.canvas = document.createElement("canvas");
this.ctx = this.canvas.getContext('2d');
this.ratio = window.devicePixelRatio;
this.canvas.width = this.elementStyles.width*this.ratio;
this.canvas.height = this.elementStyles.height*this.ratio;
this.element.appendChild(this.canvas);
this.canvas.style.width = this.elementStyles.width + 'px';
this.ctx.font = this.font = this.elementStyles.fontStyle + ' '
+ multiplyValue(this.elementStyles.fontSize, this.ratio) + ' '
+ this.elementStyles.fontFamily;
// determine the text-underline-width / strokeWidth
var dotWidth = this.ctx.measureText('.')['width'];
if (this.underlineStyles['text-underline-width'] == "auto") {
// if set to auto, calculate the optimized width based on font
this.strokeWidth = dotWidth/12;
} else {
//if set to px value, todo: other unit such as em?
this.strokeWidth = this.underlineStyles['text-underline-width'];
//get number value
this.strokeWidth = parseFloat(this.strokeWidth)*this.ratio;
}
// determine the text-underline-position / underlinePosition
// text-underline-position in ratio, todo: default and user set position ratio
if (this.underlineStyles['text-underline-position'] == "auto") {
// if set to auto, calculate the optimized width based on font
// console.log(this.elementStyles.baselinePositionRatio);
this.underlinePosition = parseFloat(this.elementStyles.height) * this.ratio
* ( 1 - this.elementStyles.baselinePositionRatio +
this.elementStyles.baselinePositionRatio * 0.4)
+ this.strokeWidth/2;
} else {
//if set to ratio value, todo: other unit such as em, px?
var userUnderlinePosition = parseFloat(this.underlineStyles['text-underline-position']);
// console.log(this.elementStyles.baselinePositionRatio);
this.underlinePosition = parseFloat(this.elementStyles.height) * this.ratio *
( 1 - this.elementStyles.baselinePositionRatio +
this.elementStyles.baselinePositionRatio * userUnderlinePosition)
+ this.strokeWidth/2;
}
var adjustValue = optimalStrokeWidthPos(this.strokeWidth, this.underlinePosition);
this.strokeWidth = adjustValue.strokeWidth;
this.underlinePosition = adjustValue.posY;
// todo: if last character is a space, remove the space
textWidth = this.ctx.measureText(this.text).width;
this.myString = new GuitarString(this.ctx,
new Point(0, this.underlinePosition),
new Point(textWidth, this.underlinePosition),
this.strokeWidth, this.underlineStyles['text-underline-color'], this.ratio);
this.drawHoles();
}
SingleUnderline.prototype.drawUnderline = function(){
// draw the underline
this.myString.draw();
}
SingleUnderline.prototype.drawHoles = function(){
// draw the font stroke
this.ctx.font = this.font;
this.ctx.textBaseline = 'top';
this.ctx.globalCompositeOperation = "destination-out";
this.ctx.lineWidth = 2*this.ratio + this.strokeWidth*3.6;
this.ctx.strokeStyle = 'blue';
this.ctx.beginPath();
this.ctx.strokeText(this.text, -0.2, 0);
this.ctx.fillStyle = 'green';
this.ctx.beginPath();
this.ctx.fillText(this.text, -0.2, 0);
}
SingleUnderline.prototype.clear = function(){
this.redrawActive = this.myString.redrawActive;
// clear
if(this.myString.redrawActive) {
// this.myString.clear();
this.ctx.clearRect(0, 0, this.canvas.width, this.canvas.height);
}
};
SingleUnderline.prototype.update = function(){
// update
if(this.myString.redrawActive) {
this.myString.update();
}
};
SingleUnderline.prototype.draw = function(){
// draw
if(this.redrawActive) {
this.drawUnderline();
this.drawHoles();
}
};
var getElementStyles = function(element){
// lineHeight, height, ratio, fontFamily, fontSize, fontStyle
var $this = element;
var baselinePositionRatio = baselineRatio(element);
var lineHeight = parseFloat(window.getComputedStyle($this, null)
.getPropertyValue("line-height"));
var fontFamily = window.getComputedStyle($this, null)
.getPropertyValue("font-family");
var fontSize = window.getComputedStyle($this, null)
.getPropertyValue("font-size");
var fontStyle = window.getComputedStyle($this, null)
.getPropertyValue("font-style");
var width = $this.getBoundingClientRect().width;
var height = $this.getBoundingClientRect().height;
var parentWidth = $this.parentNode.getBoundingClientRect().width;
var offsetLeft = $this.offsetLeft;
var parentOffsetLeft = $this.parentNode.offsetLeft;
var canvasLeft = parentOffsetLeft - offsetLeft;
var textIndent = offsetLeft - parentOffsetLeft;
// canvas.style.left= canvasLeft + 'px';
return {
lineHeight: lineHeight,
width: width,
height: height,
parentWidth: parentWidth,
fontFamily: fontFamily,
fontSize: fontSize,
fontStyle: fontStyle,
baselinePositionRatio: baselinePositionRatio,
canvasLeft: canvasLeft,
textIndent: textIndent
}
};
window.requestAnimFrame = (function(callback) {
return window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || window.oRequestAnimationFrame || window.msRequestAnimationFrame ||
function(callback) {
window.setTimeout(callback, 1000 / 60);
};
})();
var myUnderlines = [];
var myMultipleUnderlines = [];
window.onload = function() {
var underlineElements = document.querySelectorAll(".underline");
for(var n = 0; n < underlineElements.length; n++) {
var element = underlineElements[n];
var underlineStyles = {
'text-underline-color': '#000',
'text-underline-position': 'auto', // could be ratio or todo: px
'text-underline-skip': true,
'text-underline-width': 'auto' // could be auto or px or ratio
}
var elementStyles = getElementStyles(element);
// single line or multiple line?
if (elementStyles.height > elementStyles.lineHeight) {
// multiple lines
// console.log('multiple lines');
var myUnderline = new MultipleUnderline(element, underlineStyles, elementStyles);
// myUnderline.update();
// myUnderline.draw();
myUnderlines.push(myUnderline);
} else {
// single line
var myUnderline = new SingleUnderline(element, underlineStyles, elementStyles);
myUnderlines.push(myUnderline);
}
// if(window.device)
}
}
function animate() {
for(var i = 0; i < myUnderlines.length; i++) {
var myUnderline = myUnderlines[i];
// clear
myUnderline.clear();
// update
myUnderline.update();
// draw stuff
myUnderline.draw();
}
// request new frame
requestAnimFrame(function() {
animate();
});
}
animate();
//audio play multiple channels at the same time: http://www.storiesinflight.com/html5/audio.html
var channel_max = 10; // number of channels
audiochannels = new Array();
for (a = 0; a < channel_max; a++) { // prepare the channels
audiochannels[a] = new Array();
audiochannels[a]['channel'] = new Audio(); // create a new audio object
audiochannels[a]['finished'] = -1; // expected end time for this channel
}
function play_multi_sound(s) {
for (a = 0; a < audiochannels.length; a++) {
thistime = new Date();
if (audiochannels[a]['finished'] < thistime.getTime()) { // is this channel finished?
audiochannels[a]['finished'] = thistime.getTime() + document.getElementById(s).duration * 1000;
audiochannels[a]['channel'].src = document.getElementById(s).src;
audiochannels[a]['channel'].load();
audiochannels[a]['channel'].play();
break;
}
}
}
var is_chrome = navigator.userAgent.toLowerCase().indexOf('chrome') > -1;
var circleCenter = function(startPoint, thirdPoint, endPoint){
var dy1 = thirdPoint.y - startPoint.y;
var dx1 = thirdPoint.x - startPoint.x;
var dy2 = endPoint.y - thirdPoint.y;
var dx2 = endPoint.x - thirdPoint.x;
var aSlope = dy1/dx1;
var bSlope = dy2/dx2;
var centerX = (aSlope*bSlope*(startPoint.y - endPoint.y) + bSlope*(startPoint.x + thirdPoint.x)
- aSlope*(thirdPoint.x+endPoint.x) )/( 2* (bSlope-aSlope) );
var centerY = -1*(centerX - (startPoint.x+thirdPoint.x)/2)/aSlope + (startPoint.y+thirdPoint.y)/2;
var r = dist(centerX, centerY, startPoint.x, startPoint.y)
return {
x: centerX,
y: centerY,
r: r
};
}
var dist = function(x, y, x0, y0){
return Math.sqrt((x -= x0) * x + (y -= y0) * y);
};
var Point = function (x,y){
this.x=x;
this.y=y;
}
var intersects = function(a, b, c, d, p, q, r, s) {
// returns true if the line from (a,b)->(c,d) intersects with (p,q)->(r,s)
var det, gamma, lambda;
det = (c - a) * (s - q) - (r - p) * (d - b);
if (det === 0) {
return false;
} else {
lambda = ((s - q) * (r - a) + (p - r) * (s - b)) / det;
gamma = ((b - d) * (r - a) + (c - a) * (s - b)) / det;
return (0 < lambda && lambda < 1) && (0 < gamma && gamma < 1);
}
};
var musicLevel = function(startPoint, endPoint, ratio){
var length = dist(startPoint.x, startPoint.y, endPoint.x, endPoint.y)/ratio;
level = Math.floor(length/30);
if (level > 19 ) {
level = 19;
}
level = 19 - level
if (level < 10) {
level = '0' + level
}
return level;
};
function GuitarString(ctx, startPoint, endPoint, strokeWidth, strokeColor, ratio) {
//ctor
this.ctx = ctx;
this.canvas = ctx.canvas;
this.startPoint = startPoint;
this.endPoint = endPoint;
this.strokeWidth = strokeWidth;
this.strokeColor = strokeColor;
this.ratio = ratio;
this.level = musicLevel(this.startPoint, this.endPoint, this.ratio);
// this.canvas.width = this.canvas.clientWidth;
// this.canvas.height = this.canvas.clientHeight*1.2;
this.maxGrabDistance = this.strokeWidth * 2;
this.maxControlDistance = this.strokeWidth * 6;
this.ctx.lineWidth = this.strokeWidth;
this.ctx.strokeStyle = this.strokeColor;
this.ctx.beginPath();
this.ctx.moveTo(this.startPoint.x, this.startPoint.y);
this.ctx.lineTo(this.endPoint.x, this.endPoint.y);
this.ctx.globalCompositeOperation = "source-over";
this.ctx.stroke();
this.currentMouseX;
this.currentMouseY;
this.lastMouseX;
this.lastMouseY;
this.waveInitX = (this.startPoint.x + this.endPoint.x)/2;
this.waveInitY = this.startPoint.y - this.maxControlDistance;
this.waveCount = 0;
this.damping = 0.9;
this.thirdPoint = new Point((this.startPoint.x + this.endPoint.x)/2, this.startPoint.y);
// state flags
this.userInControl = false;
this.userPlucked = false;
this.waveInControl = false;
this.waveFinished = false;
this.initState = true;
this.lastRedraw = false;
this.redrawActive = false;
//add event listener
var self = this;
this.canvas.addEventListener('mouseover', function(event) {
self.mouseOver(self, event);
}, false);
this.canvas.addEventListener('mousemove', function(event) {
self.mouseMove(self, event);
}, false);
this.canvas.addEventListener ("mouseleave", function(event){
self.mouseLeave(self, event);
}, false);
this.canvas.addEventListener ("mouseout", function(event){
self.mouseOut(self, event);
}, false);
this.canvas.addEventListener("touchstart", function(event) {
self.touchDown(self, event);
}, false);
this.canvas.addEventListener("touchmove", function(event) {
self.touchXY(self, event);
}, false);
this.canvas.addEventListener("touchend", function(event) {
self.touchUp(self, event);
}, false);
}
GuitarString.prototype.mouseOver = function(self, event){
// console.log('mouseOver');
this.currentMouseX = event.layerX*this.ratio;
this.currentMouseX = event.layerY*this.ratio;
};
GuitarString.prototype.mouseMove = function (self, event){
// console.log('mouseMove');
this.lastMouseX = this.currentMouseX;
this.lastMouseY = this.currentMouseY;
this.currentMouseX = event.layerX * this.ratio;
this.currentMouseY = event.layerY * this.ratio;
var radius = circleCenter( new Point(this.startPoint.x, this.startPoint.y),
new Point(this.currentMouseX, this.currentMouseY),
new Point(this.endPoint.x, this.endPoint.y) ).r;
var currentWaveDistance = radius - Math.sqrt( Math.pow(radius, 2) - Math.pow((Math.abs(this.endPoint.x - this.startPoint.x))/2, 2) );
var lastRadius = circleCenter( new Point(this.startPoint.x, this.startPoint.y),
new Point(this.lastMouseX, this.lastMouseY),
new Point(this.endPoint.x, this.endPoint.y) ).r;
var lastWaveDistance = lastRadius - Math.sqrt( Math.pow(lastRadius, 2)
- Math.pow((Math.abs(this.endPoint.x - this.startPoint.x))/2, 2) );
var mouseInGrabRange = currentWaveDistance < this.maxGrabDistance
&& this.currentMouseX > this.startPoint.x
&& this.currentMouseX < this.endPoint.x;
var lastMouseOutGrabRange = !(lastWaveDistance < this.maxGrabDistance
&& this.lastMouseX > this.startPoint.x
&& this.lastMouseX < this.endPoint.x);
var mouseOutControlRange = !(currentWaveDistance < this.maxControlDistance
&& this.currentMouseX > this.startPoint.x
&& this.currentMouseX < this.endPoint.x);
var lastMouseInControlRange = lastWaveDistance < this.maxControlDistance
&& this.lastMouseX > this.startPoint.x
&& this.lastMouseY < this.endPoint.x;
var mouseCrossed = intersects(this.lastMouseX, this.lastMouseY,
this.currentMouseX, this.currentMouseY,
this.startPoint.x, this.startPoint.y,
this.endPoint.x, this.endPoint.y);
if( mouseInGrabRange && lastMouseOutGrabRange && (!this.userInControl) ){
// console.log('grab!');
this.initState = false;
this.userInControl = true;
this.waveInControl = false;
this.waveFinished = false;
this.redrawActive = true;
} else if ( mouseOutControlRange && lastMouseInControlRange && this.userInControl){
// console.log('boing!');
this.initState = false;
this.userInControl = false;
this.waveInControl = true;
this.waveFinished = false;
this.waveCount = 0;
// this.waveInitX = this.lastMouseX;
// this.waveInitY = this.lastMouseY;
this.waveInitX = (this.startPoint.x + this.endPoint.x)/2;
this.waveInitY = this.endPoint.y + this.maxControlDistance;
// play audio
play_multi_sound('audio' + this.level);
// createjs.Sound.play('cello_' + this.level);
}
if( (!this.userInControl)&&mouseCrossed ) {
// console.log('i just plucked!');
this.initState = false;
this.userInControl = false;
this.waveInControl = true;
this.waveFinished = false;
this.redrawActive = true;
this.waveCount = 0;
this.waveInitX = (this.startPoint.x + this.endPoint.y)/2;
this.waveInitY = this.endPoint.y + this.maxGrabDistance * 2 / 3;
}
};
GuitarString.prototype.mouseLeave = function(self, event){
// console.log('mouseLeave');
if( this.userInControl ) {
this.initState = false;
this.userInControl = false;
this.waveInControl = true;
this.waveFinished = false;
this.redrawActive = true;
this.waveCount = 0;
this.waveInitX = event.layerX*this.ratio;
this.waveInitY = event.layerY*this.ratio;
}
};
GuitarString.prototype.mouseOut = function(self, event){
// console.log('mouseOut');
};
GuitarString.prototype.touchDown = function(self, event){
// console.log('touchDown');
this.currentMouseX = event.layerX*this.ratio;
this.currentMouseX = event.layerY*this.ratio;
};
GuitarString.prototype.touchXY = function (self, event){
// console.log('touchMove');
this.lastMouseX = this.currentMouseX;
this.lastMouseY = this.currentMouseY;
this.currentMouseX = event.layerX * this.ratio;
this.currentMouseY = event.layerY * this.ratio;
var radius = circleCenter( new Point(this.startPoint.x, this.startPoint.y),
new Point(this.currentMouseX, this.currentMouseY),
new Point(this.endPoint.x, this.endPoint.y) ).r;
var currentWaveDistance = radius - Math.sqrt( Math.pow(radius, 2) - Math.pow((Math.abs(this.endPoint.x - this.startPoint.x))/2, 2) );
var lastRadius = circleCenter( new Point(this.startPoint.x, this.startPoint.y),
new Point(this.lastMouseX, this.lastMouseY),
new Point(this.endPoint.x, this.endPoint.y) ).r;
var lastWaveDistance = lastRadius - Math.sqrt( Math.pow(lastRadius, 2)
- Math.pow((Math.abs(this.endPoint.x - this.startPoint.x))/2, 2) );
var mouseInGrabRange = currentWaveDistance < this.maxGrabDistance
&& this.currentMouseX > this.startPoint.x
&& this.currentMouseX < this.endPoint.x;
var lastMouseOutGrabRange = !(lastWaveDistance < this.maxGrabDistance
&& this.lastMouseX > this.startPoint.x
&& this.lastMouseX < this.endPoint.x);
var mouseOutControlRange = !(currentWaveDistance < this.maxControlDistance
&& this.currentMouseX > this.startPoint.x
&& this.currentMouseX < this.endPoint.x);
var lastMouseInControlRange = lastWaveDistance < this.maxControlDistance
&& this.lastMouseX > this.startPoint.x
&& this.lastMouseY < this.endPoint.x;
var mouseCrossed = intersects(this.lastMouseX, this.lastMouseY,
this.currentMouseX, this.currentMouseY,
this.startPoint.x, this.startPoint.y,
this.endPoint.x, this.endPoint.y);
if( mouseInGrabRange && lastMouseOutGrabRange && (!this.userInControl) ){
// console.log('grab!');
this.initState = false;
this.userInControl = true;
this.waveInControl = false;
this.waveFinished = false;
this.redrawActive = true;
} else if ( mouseOutControlRange && lastMouseInControlRange && this.userInControl){
// console.log('boing!');
this.initState = false;
this.userInControl = false;
this.waveInControl = true;
this.waveFinished = false;
this.waveCount = 0;
// this.waveInitX = this.lastMouseX;
// this.waveInitY = this.lastMouseY;
this.waveInitX = (this.startPoint.x + this.endPoint.x)/2;
this.waveInitY = this.endPoint.y + this.maxControlDistance;
// play audio
play_multi_sound('audio' + this.level);
}
if( (!this.userInControl)&&mouseCrossed ) {
// console.log('i just plucked!');
this.initState = false;
this.userInControl = false;
this.waveInControl = true;
this.waveFinished = false;
this.redrawActive = true;
this.waveCount = 0;
this.waveInitX = (this.startPoint.x + this.endPoint.y)/2;
this.waveInitY = this.endPoint.y + this.maxGrabDistance * 2 / 3;
// play audio
// play_multi_sound('audio' + this.level);
}
};
GuitarString.prototype.touchUp = function(self, event){
// console.log('touchUp');
if( this.userInControl ) {
this.initState = false;
this.userInControl = false;
this.waveInControl = true;
this.waveFinished = false;
this.redrawActive = true;
this.waveCount = 0;
this.waveInitX = event.layerX*this.ratio;
this.waveInitY = event.layerY*this.ratio;
}
};
GuitarString.prototype.clear = function(){
// clear
// if(this.redrawActive){
// this.ctx.clearRect(0, 0, this.canvas.width, this.canvas.height);
// }
};
GuitarString.prototype.update = function(){
// console.log(this.redrawActive);
// if(this.redrawActive){
if ( this.userInControl ){
this.thirdPoint = new Point(this.currentMouseX, this.currentMouseY);
}
if ( this.waveInControl ){
var waveX = this.waveInitX;
var waveY = this.startPoint.y +
(this.waveInitY-this.startPoint.y)
*Math.cos(this.waveCount/5*Math.PI)
*Math.pow(this.damping, this.waveCount);
if ( Math.pow(this.damping, this.waveCount) > 0.03) {
// still waving ....
this.thirdPoint = new Point(waveX, waveY);
this.waveCount++;
} else {
// wave damped to a straight line, wave is finished
this.waveInControl = false;
this.waveFinished = true;
this.lastRedraw = true;
this.thirdPoint = new Point(waveX, waveY);
}
}
// }
}
GuitarString.prototype.draw = function(){
// if(this.redrawActive){
// draw stuff
// }
if(this.lastRedraw) {
this.drawLine();
this.lastRedraw = false;
this.redrawActive = false;
} else {
this.drawArc(this.startPoint, this.thirdPoint, this.endPoint);
}
};
GuitarString.prototype.drawLine = function(){
// draw a line instead of a flat curve when it stops redraw, pixel-perfect
this.ctx.lineWidth = this.strokeWidth;
this.ctx.strokeStyle = this.strokeColor;
this.ctx.beginPath();
this.ctx.moveTo(this.startPoint.x, this.startPoint.y);
this.ctx.lineTo(this.endPoint.x, this.endPoint.y);
this.ctx.globalCompositeOperation = "source-over";
this.ctx.stroke();
};
GuitarString.prototype.drawArc = function(startPoint, thirdPoint, endPoint){
var ctx = this.ctx;
ctx.lineWidth = this.strokeWidth;
ctx.strokeStyle = this.strokeColor;
var centerObject = circleCenter( new Point(startPoint.x, startPoint.y),
new Point(thirdPoint.x, thirdPoint.y),
new Point(endPoint.x, endPoint.y) );
var centerX = centerObject.x;
var centerY = centerObject.y;
var r = centerObject.r
var angle = Math.atan2(centerX-startPoint.x, centerY-startPoint.y);
// console.log(centerObject);
if (!angle){
ctx.beginPath();
ctx.moveTo(startPoint.x, startPoint.y);
ctx.lineTo(endPoint.x, endPoint.y);
} else {
if( angle > Math.PI/2) {
ctx.beginPath();
ctx.arc(centerX, centerY, r, Math.PI * 1.5-angle, Math.PI * 1.5 + angle, true);
} else {
ctx.beginPath();
ctx.arc(centerX, centerY, r, Math.PI * 1.5-angle, Math.PI * 1.5 + angle, false);
}
}
ctx.globalCompositeOperation = "source-over";
ctx.stroke();
}
Also see: Tab Triggers