10 Commits

Author SHA1 Message Date
Vadim Namniak 66da3411c3 updated to v0.3.1 2015-05-05 17:14:54 -04:00
Vadim Namniak a1ba88647e Merge pull request #6 from steoo/master
Fixed bug with numeric value of font-weight
2015-05-05 13:28:55 -04:00
Steoo 13abe2526c Fixed bug with numeric value of font-weight 2015-05-04 22:30:48 +02:00
Vadim Namniak ffcaf3425c Update README.md 2015-01-25 15:27:49 -05:00
Vadim Namniak 365bd4e24c Update README.md 2015-01-25 15:27:19 -05:00
Vadim Namniak 96001e64df Update README.md 2015-01-25 15:26:14 -05:00
Vadim Namniak 49fea5c2bb Update README.md 2015-01-25 15:23:53 -05:00
Vadim Namniak 020d1dee52 Update README.md 2015-01-25 15:22:28 -05:00
Vadim Namniak c75fae5ea0 Update README.md 2015-01-25 15:18:39 -05:00
Vadim Namniak 9b2c460a69 v0.3.0 justifyLines, lineHeight and allowNewLine 2015-01-25 14:53:51 -05:00
6 changed files with 311 additions and 232 deletions
+2 -1
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@@ -1 +1,2 @@
examples
examples/
.idea/
+252 -170
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@@ -1,206 +1,288 @@
/*! CanvasTextWrapper (https://github.com/namniak/CanvasTextWrapper)
* Version: 0.2.3
*
/*! CanvasTextWrapper
* https://github.com/namniak/CanvasTextWrapper
* Version: 0.3.0
* MIT License (http://www.opensource.org/licenses/mit-license.html)
* Copyright (c) 2014 Vadim Namniak
*/
(function() {
'use strict';
'use strict';
var defaultOptions = {
font: '18px Arial, sans-serif',
textAlign: 'left', // each line of text is aligned left
verticalAlign: 'top', // text lines block is aligned top
paddingX: 0, // zero px left & right text padding relative to canvas or parent
paddingY: 0, // zero px top & bottom text padding relative to canvas or parent
fitParent: false, // text is tested to fit canvas width
lineBreak: 'auto', // text fills the element's (canvas or parent) width going to a new line on a whole word
sizeToFill: false, // text is resized to fill the container (given font size is ignored)
strokeText: false // text is stroked according to context configuration.
};
var EL_WIDTH,EL_HEIGHT,MAX_TXT_WIDTH,MAX_TXT_HEIGHT;
window.CanvasTextWrapper = function(canvas, text, opts) {
var defaults = {
font: '18px Arial, sans-serif',
sizeToFill: false, // text is resized to fill the container (given font size is ignored)
lineHeight: 1, // default line height equivalent of '100%'
allowNewLine: true, // breaks text on every new line character '\n'
lineBreak: 'auto', // text fills the element's (canvas or parent) width going to a new line on a whole word
textAlign: 'left', // each line of text is aligned left
verticalAlign: 'top', // text lines block is aligned top
justifyLines: false, // lines are not justified
paddingX: 0, // 0px left & right text padding relatively to canvas or its container
paddingY: 0, // 0px top & bottom text padding relatively to canvas or its container
fitParent: false, // text is set to fit canvas width
strokeText: false // text is stroked according to context configuration
};
if (!(this instanceof CanvasTextWrapper)) {
throw new TypeError('CanvasTextWrapper constructor failed. Use "new" keyword when instantiating.');
}
var CanvasTextWrapper = function(canvas,text,options) {
if (!(this instanceof CanvasTextWrapper)) {
return new CanvasTextWrapper(canvas,text,options);
}
this.canvas = canvas;
this.text = text;
this.canvas = canvas;
this.text = text;
this.context = this.canvas.getContext('2d');
this.context.font = this.font;
this.context.textBaseline = 'bottom';
// set options to specified or default values
for (var property in defaultOptions) {
this[property] = (opts && opts[property]) ? opts[property] : defaultOptions[property];
}
for (var property in defaults) {
if (defaults.hasOwnProperty(property)) {
this[property] = (options && options[property]) ? options[property] : defaults[property];
}
}
// extract font size
this.lineHeight = parseInt(this.font.replace(/^\D+/g, ''), 10) || 18;
EL_WIDTH = (this.fitParent === false) ? this.canvas.width : this.canvas.parentNode.clientWidth;
EL_HEIGHT = (this.fitParent === false) ? this.canvas.height : this.canvas.parentNode.clientHeight;
MAX_TXT_WIDTH = EL_WIDTH - (this.paddingX * 2);
MAX_TXT_HEIGHT = EL_HEIGHT - (this.paddingY * 2);
// validate all set properties
this.validate();
this._init();
};
// basic context settings
this.context = this.canvas.getContext('2d');
this.context.font = this.font;
this.context.textBaseline = 'bottom';
CanvasTextWrapper.prototype = {
_init: function() {
/* Substituting this line that causing a bug with font-weight numeric values */
//this.fontSize = parseInt(this.font.replace(/^\D+/g,''),10) || 18;
this.drawText();
};
/* This line allow font values like : "italic 500 25px" to preserve both numeric a literal value of font-weight*/
this.fontSize = this.font.match(/\d+(px|em|\%)/g) ? +this.font.match(/\d+(px|em|\%)/g)[0].match(/\d+/g) : 18;
CanvasTextWrapper.prototype = {
this.textBlockHeight = 0;
this.lines = [];
this.newLineIndexes = [];
this.textPos = {x: 0,y: 0};
drawText: function() {
var elementWidth = (this.fitParent === false) ? this.canvas.width : this.canvas.parentNode.clientWidth;
var textPos = {
x: 0,
y: 0
};
this._setFont(this.fontSize);
this._setLineHeight();
this._validate();
this._render();
},
if (this.sizeToFill) {
// starting at 1px increase font size by 1px until text block exceeds the height of its padded container or until words break
var elementHeight = ((this.fitParent === false) ? this.canvas.height : this.canvas.parentNode.clientHeight) - (this.paddingX * 2);
var numWords = this.text.trim().split(/\s+/).length;
var fontSize = 0;
do {
this.setFontSize(++fontSize);
var lines = this.getWrappedText(elementWidth);
var textBlockHeight = lines.length * this.lineHeight;
} while (textBlockHeight < elementHeight && lines.join(' ').split(/\s+/).length == numWords);
_render: function() {
if (this.sizeToFill) {
var numWords = this.text.trim().split(/\s+/).length;
var fontSize = 0;
// use previous font size, not the one that broke the while condition
this.setFontSize(--fontSize);
}
do {
this._setFont(++fontSize);
this.lineHeight = this.fontSize;
this._wrap();
} while (this.textBlockHeight < MAX_TXT_HEIGHT && (this.lines.join(' ').split(/\s+/).length == numWords));
var lines = this.getWrappedText(elementWidth);
var textBlockHeight = lines.length * this.lineHeight;
this._setFont(--fontSize);
this.lineHeight = this.fontSize;
} else {
this._wrap();
}
// set vertical align for the whole text block
this.setTextVerticalAlign(textPos, textBlockHeight);
if (this.justifyLines && this.lineBreak === 'auto') {
this._justify();
}
for (var i = 0; i < lines.length; i++) {
this.setTextHorizontalAlign(this.context, textPos, elementWidth, lines[i]);
this._setAlignY();
this._drawText();
},
textPos.y = parseInt(textPos.y) + parseInt(this.lineHeight);
this.context.fillText(lines[i], textPos.x, textPos.y);
if (this.strokeText) {
this.context.strokeText(lines[i], textPos.x, textPos.y);
}
}
},
_setFont: function(fontSize) {
var fontParts = (!this.sizeToFill) ? this.font.split(/\b\d+px\b/i) : this.context.font.split(/\b\d+px\b/i);
this.context.font = fontParts[0] + fontSize + 'px' + fontParts[1];
this.fontSize = fontSize;
},
setFontSize: function(size) {
var fontParts = this.context.font.split(/\b\d+px\b/i);
this.context.font = fontParts[0] + size + 'px' + fontParts[1];
this.lineHeight = size;
},
_setLineHeight: function() {
if (!isNaN(this.lineHeight)) {
this.lineHeight = this.fontSize * this.lineHeight;
} else if (this.lineHeight.toString().indexOf('px') !== -1) {
this.lineHeight = parseInt(this.lineHeight);
} else if (this.lineHeight.toString().indexOf('%') !== -1) {
this.lineHeight = (parseInt(this.lineHeight) / 100) * this.fontSize;
}
},
getWrappedText: function(elementWidth) {
var maxTextLength = elementWidth - (this.paddingX * 2);
_wrap: function() {
if (this.allowNewLine) {
var newLines = this.text.trim().split('\n');
for (var i = 0,idx = 0; i < newLines.length - 1; i++) {
idx += newLines[i].trim().split(/\s+/).length;
this.newLineIndexes.push(idx)
}
}
var words = this.text.trim().split(/\s+/);
var lines = [];
var words = this.text.trim().split(/\s+/);
this._checkLength(words);
this._breakText(words);
this.checkWordsLength(this.context, words, maxTextLength);
this.breakTextIntoLines(this.context, lines, words, maxTextLength);
this.textBlockHeight = this.lines.length * this.lineHeight;
},
return lines;
},
_checkLength: function(words) {
var testString,tokenLen,sliced,leftover;
checkWordsLength: function(context, words, maxTextLength) {
for (var i = 0; i < words.length; i++) {
var testString = '';
var tokenLen = context.measureText(words[i]).width;
for (var i = 0; i < words.length; i++) {
testString = '';
tokenLen = this.context.measureText(words[i]).width;
// check if a word exceeds the element's width
if (tokenLen > maxTextLength) {
for (var k = 0; (context.measureText(testString + words[i][k]).width <= maxTextLength) && (k < words[i].length); k++) {
testString += words[i][k];
}
if (tokenLen > MAX_TXT_WIDTH) {
for (var k = 0; (this.context.measureText(testString + words[i][k]).width <= MAX_TXT_WIDTH) && (k < words[i].length); k++) {
testString += words[i][k];
}
// break the word because it's too long
var sliced = words[i].slice(0, k);
var leftover = words[i].slice(k);
words.splice(i, 1, sliced, leftover);
}
}
},
sliced = words[i].slice(0,k);
leftover = words[i].slice(k);
words.splice(i,1,sliced,leftover);
}
}
},
breakTextIntoLines: function(context, lines, words, maxTextLength) {
for (var i = 0, j = 0; i < words.length; j++) {
lines[j] = '';
_breakText: function(words) {
for (var i = 0,j = 0; i < words.length; j++) {
this.lines[j] = '';
if (this.lineBreak === 'auto') {
// put as many full words in a line as can fit element
while ((context.measureText(lines[j] + words[i]).width <= maxTextLength) && (i < words.length)) {
lines[j] += words[i] + ' ';
i++;
}
lines[j] = lines[j].trim();
} else if (this.lineBreak === 'word') {
// put each next word in a new line
lines[j] = words[i];
i++;
}
}
},
if (this.lineBreak === 'auto') {
while ((this.context.measureText(this.lines[j] + words[i]).width <= MAX_TXT_WIDTH) && (i < words.length)) {
setTextHorizontalAlign: function(context, textPos, elementWidth, line) {
if (this.textAlign === 'center') {
textPos.x = (elementWidth - context.measureText(line).width) / 2;
} else if (this.textAlign === 'right') {
textPos.x = elementWidth - context.measureText(line).width - this.paddingX;
} else {
textPos.x = this.paddingX;
}
},
this.lines[j] += words[i] + ' ';
i++;
setTextVerticalAlign: function(textPos, textBlockHeight) {
var elementHeight = (this.fitParent === false) ? this.canvas.height : this.canvas.parentNode.clientHeight;
if (this.allowNewLine) {
for (var k = 0; k < this.newLineIndexes.length; k++) {
if (this.newLineIndexes[k] === i) {
j++;
this.lines[j] = '';
break;
}
}
}
}
this.lines[j] = this.lines[j].trim();
} else {
this.lines[j] = words[i];
i++;
}
}
},
if (this.verticalAlign === 'middle') {
textPos.y = (elementHeight - textBlockHeight) / 2;
} else if (this.verticalAlign === 'bottom') {
textPos.y = elementHeight - textBlockHeight - this.paddingY;
} else {
textPos.y = this.paddingY;
}
},
_justify: function() {
var maxLen,longestLineIndex,tokenLen;
for (var i = 0; i < this.lines.length; i++) {
tokenLen = this.context.measureText(this.lines[i]).width;
validate: function() {
if (!(this.canvas instanceof HTMLCanvasElement)) {
throw new TypeError('From CanvasTextWrapper(): Element passed as the first parameter is not an instance of HTMLCanvasElement.');
}
if (typeof this.text !== 'string') {
throw new TypeError('From CanvasTextWrapper(): The second, dedicated for the text, parameter must be a string.');
}
if (isNaN(this.lineHeight)) {
throw new TypeError('From CanvasTextWrapper(): Cannot parse font size as an Integer. Check "font" property\'s value.');
}
if (this.textAlign !== 'left' && this.textAlign !== 'center' && this.textAlign !== 'right') {
throw new TypeError('From CanvasTextWrapper(): Unsupported horizontal align value is used. Property "textAlign" can only be set to "left", "center", or "right".');
}
if (this.verticalAlign !== 'top' && this.verticalAlign !== 'middle' && this.verticalAlign !== 'bottom') {
throw new TypeError('From CanvasTextWrapper(): Unsupported vertical align value is used. Property "verticalAlign" can only be set to "top", "middle", or "bottom".');
}
if (isNaN(this.paddingX)) {
throw new TypeError('From CanvasTextWrapper(): Unsupported horizontal padding value is used. Property "paddingX" must be set to a number');
}
if (isNaN(this.paddingY)) {
throw new TypeError('From CanvasTextWrapper(): Unsupported vertical padding value is used. Property "paddingY" must be set to a number.');
}
if (typeof this.fitParent !== 'boolean') {
throw new TypeError('From CanvasTextWrapper(): Property "fitParent" must be set to a Boolean.');
}
if (this.lineBreak !== 'auto' && this.lineBreak !== 'word') {
throw new TypeError('From CanvasTextWrapper(): Unsupported line break value is used. Property "lineBreak" can only be set to "auto", or "word".');
}
if (typeof this.sizeToFill !== 'boolean') {
throw new TypeError('From CanvasTextWrapper(): Property "sizeToFill" must be set to a Boolean.');
}
if (typeof this.strokeText !== 'boolean') {
throw new TypeError('From CanvasTextWrapper(): Property "strokeText" must be set to a Boolean.');
}
}
};
})();
if (!maxLen || tokenLen > maxLen) {
maxLen = tokenLen;
longestLineIndex = i;
}
}
// fill lines with extra spaces
var numWords,spaceLength,numOfSpaces,num,filler;
var delimiter = '\u200A';
for (i = 0; i < this.lines.length; i++) {
if (i === longestLineIndex) continue;
numWords = this.lines[i].trim().split(/\s+/).length;
if (numWords <= 1) continue;
this.lines[i] = this.lines[i].trim().split(/\s+/).join(delimiter);
spaceLength = this.context.measureText(delimiter).width;
numOfSpaces = (maxLen - this.context.measureText(this.lines[i]).width) / spaceLength;
num = numOfSpaces / (numWords - 1);
filler = '';
for (var j = 0; j < num; j++) {
filler += delimiter;
}
this.lines[i] = this.lines[i].trim().split(delimiter).join(filler);
//console.log('numWords:', numWords, 'numOfSpaces:', numOfSpaces, 'num:', num);
}
},
_drawText: function() {
for (var i = 0; i < this.lines.length; i++) {
this._setAlignX(this.lines[i]);
this.textPos.y = parseInt(this.textPos.y) + this.lineHeight;
this.context.fillText(this.lines[i],this.textPos.x,this.textPos.y);
if (this.strokeText) {
this.context.strokeText(this.lines[i],this.textPos.x,this.textPos.y);
}
}
},
_setAlignX: function(line) {
if (this.textAlign == 'center') {
this.textPos.x = (EL_WIDTH - this.context.measureText(line).width) / 2;
} else if (this.textAlign == 'right') {
this.textPos.x = EL_WIDTH - this.context.measureText(line).width - this.paddingX;
} else {
this.textPos.x = this.paddingX;
}
},
_setAlignY: function() {
if (this.verticalAlign == 'middle') {
this.textPos.y = (EL_HEIGHT - this.textBlockHeight) / 2;
} else if (this.verticalAlign == 'bottom') {
this.textPos.y = EL_HEIGHT - this.textBlockHeight - this.paddingY;
} else {
this.textPos.y = this.paddingY;
}
},
_validate: function() {
if (!(this.canvas instanceof HTMLCanvasElement))
throw new TypeError('The first parameter must be an instance of HTMLCanvasElement.');
if (typeof this.text !== 'string')
throw new TypeError('The second parameter must be a string.');
if (isNaN(this.fontSize))
throw new TypeError('Cannot parse "font".');
if (isNaN(this.lineHeight))
throw new TypeError('Cannot parse "lineHeight".');
if (this.textAlign.toLocaleLowerCase() !== 'left' && this.textAlign.toLocaleLowerCase() !== 'center' && this.textAlign.toLocaleLowerCase() !== 'right')
throw new TypeError('Property "textAlign" must be set to either "left", "center", or "right".');
if (this.verticalAlign.toLocaleLowerCase() !== 'top' && this.verticalAlign.toLocaleLowerCase() !== 'middle' && this.verticalAlign.toLocaleLowerCase() !== 'bottom')
throw new TypeError('Property "verticalAlign" must be set to either "top", "middle", or "bottom".');
if (typeof this.justifyLines !== 'boolean')
throw new TypeError('Property "justifyLines" must be set to a Boolean.');
if (isNaN(this.paddingX))
throw new TypeError('Property "paddingX" must be set to a Number.');
if (isNaN(this.paddingY))
throw new TypeError('Property "paddingY" must be set to a Number.');
if (typeof this.fitParent !== 'boolean')
throw new TypeError('Property "fitParent" must be set to a Boolean.');
if (this.lineBreak.toLocaleLowerCase() !== 'auto' && this.lineBreak.toLocaleLowerCase() !== 'word')
throw new TypeError('Property "lineBreak" must be set to either "auto" or "word".');
if (typeof this.sizeToFill !== 'boolean')
throw new TypeError('Property "sizeToFill" must be set to a Boolean.');
if (typeof this.strokeText !== 'boolean')
throw new TypeError('Property "strokeText" must be set to a Boolean.');
}
};
window.CanvasTextWrapper = CanvasTextWrapper;
})();
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+34 -38
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@@ -6,55 +6,51 @@ CanvasTextWrapper
new CanvasTextWrapper(HTMLCanvasElement, String [, options]);
```
```options``` - is a JavaScript object with the following available properties and values:
```options``` - is an object with the following available properties and values:
- ```font: String``` - text style that includes font size (in px), weight and family, similarly to CSS font shorthand property
- ```textAlign: "left" | "center" | "right"``` - horizontal alignment for each line
- ```verticalAlign: "top" | "middle" | "bottom"``` - vertical alignment for the whole text block
- ```paddingX: Number``` - horizontal padding in pixels set equally on both, left and right sides of the element
- ```paddingY: Number``` - vertical padding in pixels set equally on both, top and bottom sides of the element
- ```fitParent: Boolean``` - parameter that controls which element to fit where ```true``` means fit canvas parent's width instead of canvas own width
- ```lineBreak: "auto" | "word"``` - text split rule. When using ```"auto"```, text fills the element's width, going to a new line on a whole word when there's no more room. If ```"word"``` is set as value, each next word will be placed on a new line.
- ```sizeToFill: Boolean``` - ignore given font size and resize text to fill its padded container
- ```strokeText: Boolean``` - add text outline based on context configuration (make sure it doesn't contradict with other context settings such as globalCompositeOperation, etc)
- ```font:``` (String) - text style that includes font size in px, font weight, font family, etc. Similar to CSS font shorthand property
- ```lineHeight:``` (String or Number) - Number means n times font size where 1 is equivalent to '100%'. Also the property can be set in "%" or "px" using String
- ```textAlign: "left" | "center" | "right"``` - horizontal alignment of each line
- ```verticalAlign: "top" | "middle" | "bottom"``` - vertical alignment of the whole text block
- ```paddingX:``` (Number) - horizontal padding (in px) set equally on both, left and right sides
- ```paddingY:``` (Number) - vertical padding (in px) set equally on both, top and bottom sides
- ```fitParent:``` (Boolean) - if enabled, text will fit canvas container's width instead of canvas own width
- ```lineBreak: "auto" | "word"``` - text split rule. When using ```"auto"```, text goes to a next line on a whole word when there's no more room. If ```"word"``` is set as value, each next word will be placed on a new line.
- ```sizeToFill:``` (Boolean) - ignore given font size and line height and resize text to fill its padded container
- ```strokeText:``` (Boolean) - outline text based on context configuration
- ```justifyLines:``` (Boolean) - if enabled, all lines match the same width with flexed spaces between words (one-word lines are ignored).
- ```allowNewLine:``` (Boolean) if enabled, the text breaks on every new line character "\n" otherwise it'll be considered as a space
NOTE: if a single word is too long to fit the width with specified font size, it will be broken into as many lines as required on any letter of the word unless ```sizeToFill``` option is used.
NOTE: if a single word is too long to fit the width with specified font size, it will break on any letter unless ```sizeToFill``` option is enabled.
##Defaults
The default options object which values will be used if a property is not specified or no object is passed:
```
{
font: "18px Arial, sans-serif",
textAlign: "left",
verticalAlign: "top",
paddingX: 0,
paddingY: 0,
fitParent: false,
lineBreak: "auto",
sizeToFill: false,
strokeText: false
}
font: "18px Arial, sans-serif",
lineHeight: 1,
textAlign: "left",
verticalAlign: "top",
paddingX: 0,
paddingY: 0,
fitParent: false,
lineBreak: "auto",
strokeText: false
sizeToFill: false,
allowNewLine: true,
justifyLines: false
}
```
##Usage
Use standard canvas text drawing сщташпгкфешщты such as "fillStyle" and "globalCompositeOperation" when needed before using CanvasTextWrapper like so:
Configure context settings properties such as "fillStyle", "lineWidth" or "strokeStyle" before using CanvasTextWrapper like so:
```
var canvas = document.createElement('canvas');
canvas.width = 300;
canvas.height = 250;
var canvas = document.getElementById("#canvasText");
canvas.width = 200;
canvas.height = 200;
context = canvas.getContext("2d");
context.fillStyle = "rgb(255, 255, 255)";
context.fillRect(0, 0, canvas.width, canvas.height);
new CanvasTextWrapper(canvas, "Hi there", {
font: "normal 40px Open Sans, sans-serif",
textAlign: "center",
verticalAlign: "bottom",
paddingY: 10,
lineBreak: "word",
});
context.lineWidth = 2;
context.strokeStyle = "#ff0000";
CanvasTextWrapper(canvas,"Hello"); //default options will apply
```
##Examples
+16 -16
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@@ -1,18 +1,18 @@
{
"name": "canvas-text-wrapper",
"version": "0.2.3",
"ignore": [
"**/.*",
"**/*.log",
"**/*.json",
"Gruntfile.js",
"examples",
"node_modules",
"README.md"
],
"repository": {
"type": "git",
"url": "git://github.com/namniak/CanvasTextWrapper.git"
},
"homepage": "http://namniak.github.io/CanvasTextWrapper/"
"name": "canvas-text-wrapper",
"version": "0.3.1",
"ignore": [
"**/.*",
"**/*.log",
"**/*.json",
"Gruntfile.js",
"examples",
"node_modules",
"README.md"
],
"repository": {
"type": "git",
"url": "git://github.com/namniak/CanvasTextWrapper.git"
},
"homepage": "http://namniak.github.io/CanvasTextWrapper/"
}
+3 -3
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@@ -1,7 +1,7 @@
{
"name": "canvas-text-wrapper",
"description": "JavaScript canvas text wrapper that automatically splits a string into lines on specified rule with optional alignments and padding.",
"version": "0.2.3",
"description": "Pure JavaScript canvas text wrapper that automatically splits a string into lines on specified rule with alignment and padding.",
"version": "0.3.1",
"license": "MIT",
"main": "CanvasTextWrapper.min.js",
"homepage": "http://namniak.github.io/CanvasTextWrapper/",
@@ -13,4 +13,4 @@
"bugs": {
"url": "https://github.com/namniak/CanvasTextWrapper/issues"
}
}
}