/**
* Text Stimulus.
*
* @author Alain Pitiot
* @version 2021.1.1
* @copyright (c) 2017-2020 Ilixa Ltd. (http://ilixa.com) (c) 2020 Open Science Tools Ltd. (https://opensciencetools.org)
* @license Distributed under the terms of the MIT License
*/
import {VisualStim} from './VisualStim';
import {Color} from '../util/Color';
import {ColorMixin} from '../util/ColorMixin';
import * as util from '../util/Util';
/**
* @name module:visual.TextStim
* @class
* @extends VisualStim
* @mixes ColorMixin
* @param {Object} options
* @param {String} options.name - the name used when logging messages from this stimulus
* @param {module:core.Window} options.win - the associated Window
* @param {string} [options.text="Hello World"] - the text to be rendered
* @param {string} [options.font= "Arial"] - the font family
* @param {Array.<number>} [options.pos= [0, 0]] - the position of the center of the text
* @param {Color} [options.color= 'white'] the background color
* @param {number} [options.opacity= 1.0] - the opacity
* @param {number} [options.depth= 0] - the depth (i.e. the z order)
* @param {number} [options.contrast= 1.0] - the contrast
* @param {string} [options.units= "norm"] - the units of the text size and position
* @param {number} options.ori - the orientation (in degrees)
* @param {number} [options.height= 0.1] - the height of the text
* @param {boolean} [options.bold= false] - whether or not the text is bold
* @param {boolean} [options.italic= false] - whether or not the text is italic
* @param {string} [options.alignHoriz = 'center'] - horizontal alignment
* @param {string} [options.alignVert = 'center'] - vertical alignment
* @param {boolean} options.wrapWidth - whether or not to wrap the text horizontally
* @param {boolean} [options.flipHoriz= false] - whether or not to flip the text horizontally
* @param {boolean} [options.flipVert= false] - whether or not to flip the text vertically
* @param {PIXI.Graphics} [options.clipMask= null] - the clip mask
* @param {boolean} [options.autoDraw= false] - whether or not the stimulus should be automatically drawn on every frame flip
* @param {boolean} [options.autoLog= false] - whether or not to log
*
* @todo vertical alignment, and orientation are currently NOT implemented
*/
export class TextStim extends util.mix(VisualStim).with(ColorMixin)
{
constructor({name, win, text, font, pos, color, opacity, depth, contrast, units, ori, height, bold, italic, alignHoriz, alignVert, wrapWidth, flipHoriz, flipVert, clipMask, autoDraw, autoLog} = {})
{
super({name, win, units, ori, opacity, depth, pos, clipMask, autoDraw, autoLog});
// callback to deal with text metrics invalidation:
const onChange = (withPixi = false, withBoundingBox = false, withMetrics = false) =>
{
const visualOnChange = this._onChange(withPixi, withBoundingBox);
return () =>
{
visualOnChange();
if (withMetrics)
{
this._textMetrics = undefined;
}
};
};
// text and font:
this._addAttribute(
'text',
text,
'Hello World',
onChange(true, true, true)
);
this._addAttribute(
'alignHoriz',
alignHoriz,
'center',
onChange(true, true, true)
);
this._addAttribute(
'alignVert',
alignVert,
'center',
onChange(true, true, true)
);
this._addAttribute(
'flipHoriz',
flipHoriz,
false,
onChange(true, true, true)
);
this._addAttribute(
'flipVert',
flipVert,
false,
onChange(true, true, true)
);
this._addAttribute(
'font',
font,
'Arial',
this._onChange(true, true)
);
this._addAttribute(
'height',
height,
this._getDefaultLetterHeight(),
onChange(true, true, true)
);
this._addAttribute(
'wrapWidth',
wrapWidth,
this._getDefaultWrapWidth(),
onChange(true, true, true)
);
this._addAttribute(
'bold',
bold,
false,
onChange(true, true, true)
);
this._addAttribute(
'italic',
italic,
false,
onChange(true, true, true)
);
// color:
this._addAttribute(
'color',
color,
'white',
this._onChange(true, false)
);
this._addAttribute(
'contrast',
contrast,
1.0,
this._onChange(true, false)
);
// estimate the bounding box (using TextMetrics):
this._estimateBoundingBox();
if (this._autoLog)
{
this._psychoJS.experimentLogger.exp(`Created ${this.name} = ${this.toString()}`);
}
}
/**
* Get the metrics estimated for the text and style.
*
* Note: getTextMetrics does not require the PIXI representation of the stimulus to be instantiated,
* unlike getSize().
*
* @name module:visual.TextStim#getTextMetrics
* @public
*/
getTextMetrics()
{
if (typeof this._textMetrics === 'undefined')
{
this._textMetrics = PIXI.TextMetrics.measureText(this._text, this._getTextStyle());
}
return this._textMetrics;
}
/**
* Get the default letter height given the stimulus' units.
*
* @name module:visual.TextStim#_getDefaultLetterHeight
* @return {number} - the letter height corresponding to this stimulus' units.
* @protected
*/
_getDefaultLetterHeight()
{
const height = TextStim._defaultLetterHeightMap.get(this._units);
if (typeof height === 'undefined')
{
throw {
origin: 'TextStim._getDefaultLetterHeight',
context: 'when getting the default height of TextStim: ' + this._name,
error: 'no default letter height for unit: ' + this._units
};
}
return height;
}
/**
* Get the default wrap width given the stimulus' units.
*
* @name module:visual.TextStim#_getDefaultWrapWidth
* @return {number} - the wrap width corresponding to this stimulus' units.
* @protected
*/
_getDefaultWrapWidth()
{
const wrapWidth = TextStim._defaultWrapWidthMap.get(this._units);
if (typeof wrapWidth === 'undefined')
{
throw {
origin: 'TextStim._getDefaultWrapWidth',
context: 'when getting the default wrap width of TextStim: ' + this._name,
error: 'no default wrap width for unit: ' + this._units
};
}
return wrapWidth;
}
/**
* Estimate the bounding box.
*
* @name module:visual.TextStim#_estimateBoundingBox
* @function
* @override
* @protected
*/
_estimateBoundingBox()
{
// size of the text, irrespective of the orientation:
const textMetrics = this.getTextMetrics();
const textSize = util.to_unit(
[textMetrics.width, textMetrics.height],
'pix',
this._win,
this._units
);
// take the alignment into account:
const anchor = this._getAnchor();
this._boundingBox = new PIXI.Rectangle(
this._pos[0] - anchor[0] * textSize[0],
this._pos[1] - anchor[1] * textSize[1],
textSize[0],
textSize[1]
);
// TODO take the orientation into account
}
/**
* Get the PIXI Text Style applied to the PIXI.Text
*
* @name module:visual.TextStim#_getTextStyle
* @private
*/
_getTextStyle()
{
return new PIXI.TextStyle({
fontFamily: this._font,
fontSize: Math.round(this._getLengthPix(this._height)),
fontWeight: (this._bold) ? 'bold' : 'normal',
fontStyle: (this._italic) ? 'italic' : 'normal',
fill: this.getContrastedColor(new Color(this._color), this._contrast).hex,
align: this._alignHoriz,
wordWrap: (typeof this._wrapWidth !== 'undefined'),
wordWrapWidth: (typeof this._wrapWidth !== 'undefined') ? this._getHorLengthPix(this._wrapWidth) : 0
});
}
/**
* Update the stimulus, if necessary.
*
* @name module:visual.TextStim#_updateIfNeeded
* @function
* @private
*/
_updateIfNeeded()
{
if (!this._needUpdate)
{
return;
}
this._needUpdate = false;
// update the PIXI representation, if need be:
if (this._needPixiUpdate)
{
this._needPixiUpdate = false;
if (typeof this._pixi !== 'undefined')
{
this._pixi.destroy(true);
}
this._pixi = new PIXI.Text(this._text, this._getTextStyle());
}
const anchor = this._getAnchor();
[this._pixi.anchor.x, this._pixi.anchor.y] = anchor;
this._pixi.scale.x = this._flipHoriz ? -1 : 1;
this._pixi.scale.y = this._flipVert ? 1 : -1;
this._pixi.rotation = this._ori * Math.PI / 180;
this._pixi.position = util.to_pixiPoint(this.pos, this.units, this.win);
this._pixi.alpha = this._opacity;
this._pixi.zIndex = this._depth;
// apply the clip mask:
this._pixi.mask = this._clipMask;
// update the size attributes:
this._size = [
this._getLengthUnits(Math.abs(this._pixi.width)),
this._getLengthUnits(Math.abs(this._pixi.height))
];
// refine the estimate of the bounding box:
this._boundingBox = new PIXI.Rectangle(
this._pos[0] - anchor[0] * this._size[0],
this._pos[1] - anchor[1] * this._size[1],
this._size[0],
this._size[1]
);
}
/**
* Convert the alignment attributes into an anchor.
*
* @name module:visual.TextStim#_getAnchor
* @function
* @private
* @return {number[]} - the anchor
*/
_getAnchor()
{
let anchor = [];
switch (this._alignHoriz)
{
case 'left':
anchor.push(0);
break;
case 'right':
anchor.push(1);
break;
default:
case 'center':
anchor.push(0.5);
}
switch (this._alignVert)
{
case 'top':
anchor.push(0);
break;
case 'bottom':
anchor.push(1);
break;
default:
case 'center':
anchor.push(0.5);
}
return anchor;
}
}
/**
* <p>This map associates units to default letter height.</p>
*
* @name module:visual.TextStim#_defaultLetterHeightMap
* @readonly
* @private
*/
TextStim._defaultLetterHeightMap = new Map([
['cm', 1.0],
['deg', 1.0],
['degs', 1.0],
['degFlatPos', 1.0],
['degFlat', 1.0],
['norm', 0.1],
['height', 0.2],
['pix', 20],
['pixels', 20]
]);
/**
* <p>This map associates units to default wrap width.</p>
*
* @name module:visual.TextStim#_defaultLetterHeightMap
* @readonly
* @private
*/
TextStim._defaultWrapWidthMap = new Map([
['cm', 15.0],
['deg', 15.0],
['degs', 15.0],
['degFlatPos', 15.0],
['degFlat', 15.0],
['norm', 1],
['height', 1],
['pix', 500],
['pixels', 500]
]);