const Sprite = require('../sprites/Sprite');
const Texture = require('../textures/Texture');
const math = require('../math');
const utils = require('../utils');
const CONST = require('../../const');
/**
* A Text Object will create a line or multiple lines of text. To split a line you can use '\n' in your text string,
* or add a wordWrap property set to true and and wordWrapWidth property with a value in the style object.
*
* A Text can be created directly from a string and a style object
*
* ```js
* var text = new Text('This is a pixi text',{font : '24px Arial', fill : 0xff1010, align : 'center'});
* ```
*
* @class
* @extends Sprite
* @param text {string} The copy that you would like the text to display
* @param [style] {object} The style parameters
* @param [style.font] {string} default 'bold 20px Arial' The style and size of the font
* @param [style.fill='black'] {String|Number} A canvas fillstyle that will be used on the text e.g 'red', '#00FF00'
* @param [style.align='left'] {string} Alignment for multiline text ('left', 'center' or 'right'), does not affect single line text
* @param [style.stroke] {String|Number} A canvas fillstyle that will be used on the text stroke e.g 'blue', '#FCFF00'
* @param [style.strokeThickness=0] {number} A number that represents the thickness of the stroke. Default is 0 (no stroke)
* @param [style.wordWrap=false] {boolean} Indicates if word wrap should be used
* @param [style.wordWrapWidth=100] {number} The width at which text will wrap, it needs wordWrap to be set to true
* @param [style.letterSpacing=0] {number} The amount of spacing between letters, default is 0
* @param [style.breakWords=false] {boolean} Indicates if lines can be wrapped within words, it needs wordWrap to be set to true
* @param [style.lineHeight] {number} The line height, a number that represents the vertical space that a letter uses
* @param [style.dropShadow=false] {boolean} Set a drop shadow for the text
* @param [style.dropShadowColor='#000000'] {string} A fill style to be used on the dropshadow e.g 'red', '#00FF00'
* @param [style.dropShadowAngle=Math.PI/4] {number} Set a angle of the drop shadow
* @param [style.dropShadowDistance=5] {number} Set a distance of the drop shadow
* @param [style.dropShadowBlur=0] {number} Set a shadow blur radius
* @param [style.padding=0] {number} Occasionally some fonts are cropped on top or bottom. Adding some padding will
* prevent this from happening by adding padding to the top and bottom of text height.
* @param [style.textBaseline='alphabetic'] {string} The baseline of the text that is rendered.
* @param [style.lineJoin='miter'] {string} The lineJoin property sets the type of corner created, it can resolve
* spiked text issues. Default is 'miter' (creates a sharp corner).
* @param [style.miterLimit=10] {number} The miter limit to use when using the 'miter' lineJoin mode. This can reduce
* or increase the spikiness of rendered text.
*/
class Text extends Sprite {
constructor(text, style, resolution) {
super();
/**
* The canvas element that everything is drawn to
*
* @member {HTMLCanvasElement}
*/
this.canvas = document.createElement('canvas');
/**
* The canvas 2d context that everything is drawn with
* @member {HTMLCanvasElement}
*/
this.context = this.canvas.getContext('2d');
/**
* The resolution of the canvas.
* @member {number}
*/
this.resolution = resolution || CONST.RESOLUTION;
/**
* Private tracker for the current text.
*
* @member {string}
* @private
*/
this._text = null;
/**
* Private tracker for the current style.
*
* @member {object}
* @private
*/
this._style = null;
var texture = Texture.fromCanvas(this.canvas);
texture.trim = new math.Rectangle();
this.texture = texture;
this.text = text;
this.style = style;
}
/**
* Renders text and updates it when needed
*
* @private
*/
updateText() {
var style = this._style;
this.context.font = style.font;
// word wrap
// preserve original text
var outputText = style.wordWrap ? this.wordWrap(this._text) : this._text;
// split text into lines
var lines = outputText.split(/(?:\r\n|\r|\n)/);
// calculate text width
var lineWidths = new Array(lines.length);
var maxLineWidth = 0;
var fontProperties = this.determineFontProperties(style.font);
for (var i = 0; i < lines.length; i++) {
var lineWidth = this.context.measureText(lines[i]).width + ((lines[i].length - 1) * style.letterSpacing);
lineWidths[i] = lineWidth;
maxLineWidth = Math.max(maxLineWidth, lineWidth);
}
var width = maxLineWidth + style.strokeThickness;
if (style.dropShadow) {
width += style.dropShadowDistance;
}
this.canvas.width = Math.ceil((width + this.context.lineWidth) * this.resolution);
// calculate text height
var lineHeight = this.style.lineHeight || fontProperties.fontSize + style.strokeThickness;
var height = lineHeight * lines.length;
if (style.dropShadow) {
height += style.dropShadowDistance;
}
this.canvas.height = Math.ceil((height + this._style.padding * 2) * this.resolution);
this.context.scale(this.resolution, this.resolution);
if (navigator.isCocoonJS) {
this.context.clearRect(0, 0, this.canvas.width, this.canvas.height);
}
// this.context.fillStyle="#FF0000";
// this.context.fillRect(0, 0, this.canvas.width, this.canvas.height);
this.context.font = style.font;
this.context.strokeStyle = style.stroke;
this.context.lineWidth = style.strokeThickness;
this.context.textBaseline = style.textBaseline;
this.context.lineJoin = style.lineJoin;
this.context.miterLimit = style.miterLimit;
var linePositionX;
var linePositionY;
if (style.dropShadow) {
if (style.dropShadowBlur > 0) {
this.context.shadowColor = style.dropShadowColor;
this.context.shadowBlur = style.dropShadowBlur;
}
else {
this.context.fillStyle = style.dropShadowColor;
}
var xShadowOffset = Math.cos(style.dropShadowAngle) * style.dropShadowDistance;
var yShadowOffset = Math.sin(style.dropShadowAngle) * style.dropShadowDistance;
for (i = 0; i < lines.length; i++) {
linePositionX = style.strokeThickness / 2;
linePositionY = (style.strokeThickness / 2 + i * lineHeight) + fontProperties.ascent;
if (style.align === 'right') {
linePositionX += maxLineWidth - lineWidths[i];
}
else if (style.align === 'center') {
linePositionX += (maxLineWidth - lineWidths[i]) / 2;
}
if (style.fill) {
this.drawLetterSpacing(lines[i], linePositionX + xShadowOffset, linePositionY + yShadowOffset + style.padding);
}
}
}
// set canvas text styles
this.context.fillStyle = style.fill;
// draw lines line by line
for (i = 0; i < lines.length; i++) {
linePositionX = style.strokeThickness / 2;
linePositionY = (style.strokeThickness / 2 + i * lineHeight) + fontProperties.ascent;
if (style.align === 'right') {
linePositionX += maxLineWidth - lineWidths[i];
}
else if (style.align === 'center') {
linePositionX += (maxLineWidth - lineWidths[i]) / 2;
}
if (style.stroke && style.strokeThickness) {
this.drawLetterSpacing(lines[i], linePositionX, linePositionY + style.padding, true);
}
if (style.fill) {
this.drawLetterSpacing(lines[i], linePositionX, linePositionY + style.padding);
}
}
this.updateTexture();
}
/**
* Render the text with letter-spacing.
*
* @private
*/
drawLetterSpacing(text, x, y, isStroke) {
var style = this._style;
// letterSpacing of 0 means normal
var letterSpacing = style.letterSpacing;
if (letterSpacing === 0) {
if (isStroke) {
this.context.strokeText(text, x, y);
}
else {
this.context.fillText(text, x, y);
}
return;
}
var characters = String.prototype.split.call(text, ''),
index = 0,
current,
currentPosition = x;
while (index < text.length) {
current = characters[index++];
if (isStroke) {
this.context.strokeText(current, currentPosition, y);
}
else {
this.context.fillText(current, currentPosition, y);
}
currentPosition += this.context.measureText(current).width + letterSpacing;
}
}
/**
* Updates texture size based on canvas size
*
* @private
*/
updateTexture() {
var texture = this._texture;
var style = this._style;
texture.baseTexture.hasLoaded = true;
texture.baseTexture.resolution = this.resolution;
texture.baseTexture.width = this.canvas.width / this.resolution;
texture.baseTexture.height = this.canvas.height / this.resolution;
texture.crop.width = texture._frame.width = this.canvas.width / this.resolution;
texture.crop.height = texture._frame.height = this.canvas.height / this.resolution;
texture.trim.x = 0;
texture.trim.y = -style.padding;
texture.trim.width = texture._frame.width;
texture.trim.height = texture._frame.height - style.padding * 2;
this._width = this.canvas.width / this.resolution;
this._height = this.canvas.height / this.resolution;
texture.baseTexture.emit('update', texture.baseTexture);
this.dirty = false;
}
/**
* Renders the object using the WebGL renderer
*
* @param renderer {WebGLRenderer}
*/
renderWebGL(renderer) {
if (this.dirty) {
// this.resolution = 1//renderer.resolution;
this.updateText();
}
super.renderWebGL(renderer);
}
/**
* Renders the object using the Canvas renderer
*
* @param renderer {CanvasRenderer}
* @private
*/
_renderCanvas(renderer) {
if (this.dirty) {
// this.resolution = 1//renderer.resolution;
this.updateText();
}
super._renderCanvas(renderer);
}
/**
* Calculates the ascent, descent and fontSize of a given fontStyle
*
* @param fontStyle {object}
* @private
*/
determineFontProperties(fontStyle) {
var properties = Text.fontPropertiesCache[fontStyle];
if (!properties) {
properties = {};
var canvas = Text.fontPropertiesCanvas;
var context = Text.fontPropertiesContext;
context.font = fontStyle;
var width = Math.ceil(context.measureText('|MÉq').width);
var baseline = Math.ceil(context.measureText('M').width);
var height = 2 * baseline;
baseline = baseline * 1.4 | 0;
canvas.width = width;
canvas.height = height;
context.fillStyle = '#f00';
context.fillRect(0, 0, width, height);
context.font = fontStyle;
context.textBaseline = 'alphabetic';
context.fillStyle = '#000';
context.fillText('|MÉq', 0, baseline);
var imagedata = context.getImageData(0, 0, width, height).data;
var pixels = imagedata.length;
var line = width * 4;
var i, j;
var idx = 0;
var stop = false;
// ascent. scan from top to bottom until we find a non red pixel
for (i = 0; i < baseline; i++) {
for (j = 0; j < line; j += 4) {
if (imagedata[idx + j] !== 255) {
stop = true;
break;
}
}
if (!stop) {
idx += line;
}
else {
break;
}
}
properties.ascent = baseline - i;
idx = pixels - line;
stop = false;
// descent. scan from bottom to top until we find a non red pixel
for (i = height; i > baseline; i--) {
for (j = 0; j < line; j += 4) {
if (imagedata[idx + j] !== 255) {
stop = true;
break;
}
}
if (!stop) {
idx -= line;
}
else {
break;
}
}
properties.descent = i - baseline;
properties.fontSize = properties.ascent + properties.descent;
Text.fontPropertiesCache[fontStyle] = properties;
}
return properties;
}
/**
* Applies newlines to a string to have it optimally fit into the horizontal
* bounds set by the Text object's wordWrapWidth property.
*
* @param text {string}
* @private
*/
wordWrap(text) {
// Greedy wrapping algorithm that will wrap words as the line grows longer
// than its horizontal bounds.
var result = '';
var lines = text.split('\n');
var wordWrapWidth = this._style.wordWrapWidth;
for (var i = 0; i < lines.length; i++) {
var spaceLeft = wordWrapWidth;
var words = lines[i].split(' ');
for (var j = 0; j < words.length; j++) {
var wordWidth = this.context.measureText(words[j]).width;
if (this._style.breakWords && wordWidth > wordWrapWidth) {
// Word should be split in the middle
var characters = words[j].split('');
for (var c = 0; c < characters.length; c++) {
var characterWidth = this.context.measureText(characters[c]).width;
if (characterWidth > spaceLeft) {
result += '\n' + characters[c];
spaceLeft = wordWrapWidth - characterWidth;
}
else {
if (c === 0) {
result += ' ';
}
result += characters[c];
spaceLeft -= characterWidth;
}
}
}
else {
var wordWidthWithSpace = wordWidth + this.context.measureText(' ').width;
if (j === 0 || wordWidthWithSpace > spaceLeft) {
// Skip printing the newline if it's the first word of the line that is
// greater than the word wrap width.
if (j > 0) {
result += '\n';
}
result += words[j];
spaceLeft = wordWrapWidth - wordWidth;
}
else {
spaceLeft -= wordWidthWithSpace;
result += ' ' + words[j];
}
}
}
if (i < lines.length - 1) {
result += '\n';
}
}
return result;
}
/**
* Returns the bounds of the Text as a rectangle. The bounds calculation takes the worldTransform into account.
*
* @param matrix {Matrix} the transformation matrix of the Text
* @return {Rectangle} the framing rectangle
*/
getBounds(matrix) {
if (this.dirty) {
this.updateText();
}
return super.getBounds(matrix);
}
/**
* Destroys this text object.
*
* @param [destroyBaseTexture=true] {boolean} whether to destroy the base texture as well
*/
destroy(destroyBaseTexture) {
// make sure to reset the the context and canvas.. dont want this hanging around in memory!
this.context = null;
this.canvas = null;
this._style = null;
this._texture.destroy(destroyBaseTexture === undefined ? true : destroyBaseTexture);
}
}
Text.fontPropertiesCache = {};
Text.fontPropertiesCanvas = document.createElement('canvas');
Text.fontPropertiesContext = Text.fontPropertiesCanvas.getContext('2d');
Object.defineProperties(Text.prototype, {
/**
* The width of the Text, setting this will actually modify the scale to achieve the value set
*
* @member {number}
* @memberof Text#
*/
width: {
get: function() {
if (this.dirty) {
this.updateText();
}
return this.scale.x * this._texture._frame.width;
},
set: function(value) {
this.scale.x = value / this._texture._frame.width;
this._width = value;
},
},
/**
* The height of the Text, setting this will actually modify the scale to achieve the value set
*
* @member {number}
* @memberof Text#
*/
height: {
get: function() {
if (this.dirty) {
this.updateText();
}
return this.scale.y * this._texture._frame.height;
},
set: function(value) {
this.scale.y = value / this._texture._frame.height;
this._height = value;
},
},
/**
* Set the style of the text
*
* @param [style] {object} The style parameters
* @param [style.font='bold 20pt Arial'] {string} The style and size of the font
* @param [style.fill='black'] {string|number} A canvas fillstyle that will be used on the text eg 'red', '#00FF00'
* @param [style.align='left'] {string} Alignment for multiline text ('left', 'center' or 'right'), does not affect single line text
* @param [style.stroke='black'] {string|number} A canvas fillstyle that will be used on the text stroke eg 'blue', '#FCFF00'
* @param [style.strokeThickness=0] {number} A number that represents the thickness of the stroke. Default is 0 (no stroke)
* @param [style.wordWrap=false] {boolean} Indicates if word wrap should be used
* @param [style.wordWrapWidth=100] {number} The width at which text will wrap
* @param [style.lineHeight] {number} The line height, a number that represents the vertical space that a letter uses
* @param [style.dropShadow=false] {boolean} Set a drop shadow for the text
* @param [style.dropShadowColor='#000000'] {string|number} A fill style to be used on the dropshadow e.g 'red', '#00FF00'
* @param [style.dropShadowAngle=Math.PI/6] {number} Set a angle of the drop shadow
* @param [style.dropShadowDistance=5] {number} Set a distance of the drop shadow
* @param [style.dropShadowBlur=0] {number} Set a shadow blur radius
* @param [style.padding=0] {number} Occasionally some fonts are cropped on top or bottom. Adding some padding will
* prevent this from happening by adding padding to the top and bottom of text height.
* @param [style.textBaseline='alphabetic'] {string} The baseline of the text that is rendered.
* @param [style.lineJoin='miter'] {string} The lineJoin property sets the type of corner created, it can resolve
* spiked text issues. Default is 'miter' (creates a sharp corner).
* @param [style.miterLimit=10] {number} The miter limit to use when using the 'miter' lineJoin mode. This can reduce
* or increase the spikiness of rendered text.
* @memberof Text#
*/
style: {
get: function() {
return this._style;
},
set: function(style) {
style = style || {};
if (typeof style.fill === 'number') {
style.fill = utils.hex2string(style.fill);
}
if (typeof style.stroke === 'number') {
style.stroke = utils.hex2string(style.stroke);
}
if (typeof style.dropShadowColor === 'number') {
style.dropShadowColor = utils.hex2string(style.dropShadowColor);
}
style.font = style.font || 'bold 20pt Arial';
style.fill = style.fill || 'black';
style.align = style.align || 'left';
style.stroke = style.stroke || 'black'; // provide a default, see: https://github.com/pixijs/pixi.js/issues/136
style.strokeThickness = style.strokeThickness || 0;
style.wordWrap = style.wordWrap || false;
style.wordWrapWidth = style.wordWrapWidth || 100;
style.breakWords = style.breakWords || false;
style.letterSpacing = style.letterSpacing || 0;
style.dropShadow = style.dropShadow || false;
style.dropShadowColor = style.dropShadowColor || '#000000';
style.dropShadowAngle = style.dropShadowAngle !== undefined ? style.dropShadowAngle : Math.PI / 6;
style.dropShadowDistance = style.dropShadowDistance !== undefined ? style.dropShadowDistance : 5;
style.dropShadowBlur = style.dropShadowBlur !== undefined ? style.dropShadowBlur : 0; // shadowBlur is '0' by default according to HTML
style.padding = style.padding || 0;
style.textBaseline = style.textBaseline || 'alphabetic';
style.lineJoin = style.lineJoin || 'miter';
style.miterLimit = style.miterLimit || 10;
this._style = style;
this.dirty = true;
},
},
/**
* Set the copy for the text object. To split a line you can use '\n'.
*
* @param text {string} The copy that you would like the text to display
* @memberof Text#
*/
text: {
get: function() {
return this._text;
},
set: function(text) {
text = text.toString() || ' ';
if (this._text === text) {
return;
}
this._text = text;
this.dirty = true;
},
},
});
module.exports = Text;