/**
* Text Stimulus.
*
* @author Alain Pitiot
* @version 2022.2.3
* @copyright (c) 2017-2020 Ilixa Ltd. (http://ilixa.com) (c) 2020-2022 Open Science Tools Ltd. (https://opensciencetools.org)
* @license Distributed under the terms of the MIT License
*/
import * as PIXI from "pixi.js-legacy";
import { Color } from "../util/Color.js";
import { ColorMixin } from "../util/ColorMixin.js";
import { to_pixiPoint } from "../util/Pixi.js";
import * as util from "../util/Util.js";
import { VisualStim } from "./VisualStim.js";
/**
* <p>TextStim handles text stimuli.</p>
*
* @extends VisualStim
* @mixes ColorMixin
* @todo vertical alignment, and orientation are currently NOT implemented
*/
export class TextStim extends util.mix(VisualStim).with(ColorMixin)
{
/**
* @memberOf module:visual
* @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
*/
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),
);
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().
*/
getTextMetrics()
{
if (typeof this._textMetrics === "undefined")
{
this._textMetrics = PIXI.TextMetrics.measureText(this._text, this._getTextStyle());
// since PIXI.TextMetrics does not give us the actual bounding box of the text
// (e.g. the height is really just the ascent + descent of the font), we use measureText:
const textMetricsCanvas = document.createElement('canvas');
document.body.appendChild(textMetricsCanvas);
const ctx = textMetricsCanvas.getContext("2d");
ctx.font = this._getTextStyle().toFontString();
ctx.textBaseline = "alphabetic";
ctx.textAlign = "left";
this._textMetrics.boundingBox = ctx.measureText(this._text);
document.body.removeChild(textMetricsCanvas);
}
return this._textMetrics;
}
/**
* Get the default letter height given the 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.
*
* @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;
}
/**
* Get the bounding gox.
*
* @protected
* @param {boolean} [tight= false] - whether or not to fit as closely as possible to the text
* @return {number[]} - the bounding box, in the units of this TextStim
*/
getBoundingBox(tight = false)
{
if (tight)
{
const textMetrics_px = this.getTextMetrics();
let left_px = this._pos[0] - textMetrics_px.boundingBox.actualBoundingBoxLeft;
let top_px = this._pos[1] + textMetrics_px.fontProperties.descent - textMetrics_px.boundingBox.actualBoundingBoxDescent;
const width_px = textMetrics_px.boundingBox.actualBoundingBoxRight + textMetrics_px.boundingBox.actualBoundingBoxLeft;
const height_px = textMetrics_px.boundingBox.actualBoundingBoxAscent + textMetrics_px.boundingBox.actualBoundingBoxDescent;
// adjust the bounding box position by taking into account the anchoring of the text:
const boundingBox_px = this._getBoundingBox_px();
switch (this._alignHoriz)
{
case "left":
// nothing to do
break;
case "right":
// TODO
break;
default:
case "center":
left_px -= (boundingBox_px.width - width_px) / 2;
}
switch (this._alignVert)
{
case "top":
// TODO
break;
case "bottom":
// nothing to do
break;
default:
case "center":
top_px -= (boundingBox_px.height - height_px) / 2;
}
// convert from pixel to this stimulus' units:
const leftTop = util.to_unit(
[left_px, top_px],
"pix",
this._win,
this._units);
const dimensions = util.to_unit(
[width_px, height_px],
"pix",
this._win,
this._units);
return new PIXI.Rectangle(leftTop[0], leftTop[1], dimensions[0], dimensions[1]);
}
else
{
return this._boundingBox.clone();
}
}
/**
* Estimate the bounding box.
*
* @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] - textSize[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
*
* @protected
*/
_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,
});
}
/**
* Setter for the color attribute.
*
* @param {undefined | null | number} color - the color
* @param {boolean} [log= false] - whether of not to log
*/
setColor(color, log = false)
{
const hasChanged = this._setAttribute("color", color, log);
if (hasChanged)
{
if (typeof this._pixi !== "undefined")
{
this._pixi.style = this._getTextStyle();
this._needUpdate = true;
}
}
}
/**
* Update the stimulus, if necessary.
*
* @protected
*/
_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());
// TODO is updateText necessary?
// this._pixi.updateText();
}
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 = 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 attribute:
this._size = util.to_unit(
[Math.abs(this._pixi.width), Math.abs(this._pixi.height)],
"pix",
this._win,
this._units
);
// refine the estimate of the bounding box:
this._boundingBox = new PIXI.Rectangle(
this._pos[0] - anchor[0] * this._size[0],
this._pos[1] - this._size[1] + anchor[1] * this._size[1],
this._size[0],
this._size[1],
);
}
/**
* Convert the alignment attributes into an anchor.
*
* @protected
* @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>
*
* @readonly
* @protected
*/
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>
*
* @readonly
* @protected
*/
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],
]);