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nothoughts/node_modules/pixi.js/lib/scene/text/canvas/CanvasTextMetrics.d.ts
2025-08-04 18:57:35 +02:00

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TypeScript

import type { ICanvas } from '../../../environment/canvas/ICanvas';
import type { ICanvasRenderingContext2D } from '../../../environment/canvas/ICanvasRenderingContext2D';
import type { TextStyle } from '../TextStyle';
/**
* A number, or a string containing a number.
* @memberof text
* @typedef {object} FontMetrics
* @property {number} ascent - Font ascent
* @property {number} descent - Font descent
* @property {number} fontSize - Font size
*/
export interface FontMetrics {
ascent: number;
descent: number;
fontSize: number;
}
/**
* The TextMetrics object represents the measurement of a block of text with a specified style.
* @example
* import { TextMetrics, TextStyle } from 'pixi.js';
*
* const style = new TextStyle({
* fontFamily: 'Arial',
* fontSize: 24,
* fill: 0xff1010,
* align: 'center',
* });
* const textMetrics = TextMetrics.measureText('Your text', style);
* @memberof text
*/
export declare class CanvasTextMetrics {
/** The text that was measured. */
text: string;
/** The style that was measured. */
style: TextStyle;
/** The measured width of the text. */
width: number;
/** The measured height of the text. */
height: number;
/** An array of lines of the text broken by new lines and wrapping is specified in style. */
lines: string[];
/** An array of the line widths for each line matched to `lines`. */
lineWidths: number[];
/** The measured line height for this style. */
lineHeight: number;
/** The maximum line width for all measured lines. */
maxLineWidth: number;
/** The font properties object from TextMetrics.measureFont. */
fontProperties: FontMetrics;
/**
* String used for calculate font metrics.
* These characters are all tall to help calculate the height required for text.
*/
static METRICS_STRING: string;
/** Baseline symbol for calculate font metrics. */
static BASELINE_SYMBOL: string;
/** Baseline multiplier for calculate font metrics. */
static BASELINE_MULTIPLIER: number;
/** Height multiplier for setting height of canvas to calculate font metrics. */
static HEIGHT_MULTIPLIER: number;
/**
* A Unicode "character", or "grapheme cluster", can be composed of multiple Unicode code points,
* such as letters with diacritical marks (e.g. `'\u0065\u0301'`, letter e with acute)
* or emojis with modifiers (e.g. `'\uD83E\uDDD1\u200D\uD83D\uDCBB'`, technologist).
* The new `Intl.Segmenter` API in ES2022 can split the string into grapheme clusters correctly. If it is not available,
* PixiJS will fallback to use the iterator of String, which can only spilt the string into code points.
* If you want to get full functionality in environments that don't support `Intl.Segmenter` (such as Firefox),
* you can use other libraries such as [grapheme-splitter]{@link https://www.npmjs.com/package/grapheme-splitter}
* or [graphemer]{@link https://www.npmjs.com/package/graphemer} to create a polyfill. Since these libraries can be
* relatively large in size to handle various Unicode grapheme clusters properly, PixiJS won't use them directly.
*/
static graphemeSegmenter: (s: string) => string[];
static _experimentalLetterSpacingSupported?: boolean;
/**
* Checking that we can use modern canvas 2D API.
*
* Note: This is an unstable API, Chrome < 94 use `textLetterSpacing`, later versions use `letterSpacing`.
* @see TextMetrics.experimentalLetterSpacing
* @see https://developer.mozilla.org/en-US/docs/Web/API/ICanvasRenderingContext2D/letterSpacing
* @see https://developer.chrome.com/origintrials/#/view_trial/3585991203293757441
*/
static get experimentalLetterSpacingSupported(): boolean;
/**
* New rendering behavior for letter-spacing which uses Chrome's new native API. This will
* lead to more accurate letter-spacing results because it does not try to manually draw
* each character. However, this Chrome API is experimental and may not serve all cases yet.
* @see TextMetrics.experimentalLetterSpacingSupported
*/
static experimentalLetterSpacing: boolean;
/** Cache of {@see TextMetrics.FontMetrics} objects. */
private static _fonts;
/** Cache of new line chars. */
private static readonly _newlines;
/** Cache of breaking spaces. */
private static readonly _breakingSpaces;
private static __canvas;
private static __context;
private static readonly _measurementCache;
/**
* @param text - the text that was measured
* @param style - the style that was measured
* @param width - the measured width of the text
* @param height - the measured height of the text
* @param lines - an array of the lines of text broken by new lines and wrapping if specified in style
* @param lineWidths - an array of the line widths for each line matched to `lines`
* @param lineHeight - the measured line height for this style
* @param maxLineWidth - the maximum line width for all measured lines
* @param {FontMetrics} fontProperties - the font properties object from TextMetrics.measureFont
*/
constructor(text: string, style: TextStyle, width: number, height: number, lines: string[], lineWidths: number[], lineHeight: number, maxLineWidth: number, fontProperties: FontMetrics);
/**
* Measures the supplied string of text and returns a Rectangle.
* @param text - The text to measure.
* @param style - The text style to use for measuring
* @param canvas - optional specification of the canvas to use for measuring.
* @param wordWrap
* @returns Measured width and height of the text.
*/
static measureText(text: string, style: TextStyle, canvas?: ICanvas, wordWrap?: boolean): CanvasTextMetrics;
private static _measureText;
/**
* 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 to apply word wrapping to
* @param style - the style to use when wrapping
* @param canvas - optional specification of the canvas to use for measuring.
* @returns New string with new lines applied where required
*/
private static _wordWrap;
/**
* Convenience function for logging each line added during the wordWrap method.
* @param line - The line of text to add
* @param newLine - Add new line character to end
* @returns A formatted line
*/
private static _addLine;
/**
* Gets & sets the widths of calculated characters in a cache object
* @param key - The key
* @param letterSpacing - The letter spacing
* @param cache - The cache
* @param context - The canvas context
* @returns The from cache.
*/
private static _getFromCache;
/**
* Determines whether we should collapse breaking spaces.
* @param whiteSpace - The TextStyle property whiteSpace
* @returns Should collapse
*/
private static _collapseSpaces;
/**
* Determines whether we should collapse newLine chars.
* @param whiteSpace - The white space
* @returns should collapse
*/
private static _collapseNewlines;
/**
* Trims breaking whitespaces from string.
* @param text - The text
* @returns Trimmed string
*/
private static _trimRight;
/**
* Determines if char is a newline.
* @param char - The character
* @returns True if newline, False otherwise.
*/
private static _isNewline;
/**
* Determines if char is a breaking whitespace.
*
* It allows one to determine whether char should be a breaking whitespace
* For example certain characters in CJK langs or numbers.
* It must return a boolean.
* @param char - The character
* @param [_nextChar] - The next character
* @returns True if whitespace, False otherwise.
*/
static isBreakingSpace(char: string, _nextChar?: string): boolean;
/**
* Splits a string into words, breaking-spaces and newLine characters
* @param text - The text
* @returns A tokenized array
*/
private static _tokenize;
/**
* Overridable helper method used internally by TextMetrics, exposed to allow customizing the class's behavior.
*
* It allows one to customise which words should break
* Examples are if the token is CJK or numbers.
* It must return a boolean.
* @param _token - The token
* @param breakWords - The style attr break words
* @returns Whether to break word or not
*/
static canBreakWords(_token: string, breakWords: boolean): boolean;
/**
* Overridable helper method used internally by TextMetrics, exposed to allow customizing the class's behavior.
*
* It allows one to determine whether a pair of characters
* should be broken by newlines
* For example certain characters in CJK langs or numbers.
* It must return a boolean.
* @param _char - The character
* @param _nextChar - The next character
* @param _token - The token/word the characters are from
* @param _index - The index in the token of the char
* @param _breakWords - The style attr break words
* @returns whether to break word or not
*/
static canBreakChars(_char: string, _nextChar: string, _token: string, _index: number, _breakWords: boolean): boolean;
/**
* Overridable helper method used internally by TextMetrics, exposed to allow customizing the class's behavior.
*
* It is called when a token (usually a word) has to be split into separate pieces
* in order to determine the point to break a word.
* It must return an array of characters.
* @param token - The token to split
* @returns The characters of the token
* @see CanvasTextMetrics.graphemeSegmenter
*/
static wordWrapSplit(token: string): string[];
/**
* Calculates the ascent, descent and fontSize of a given font-style
* @param font - String representing the style of the font
* @returns Font properties object
*/
static measureFont(font: string): FontMetrics;
/**
* Clear font metrics in metrics cache.
* @param {string} [font] - font name. If font name not set then clear cache for all fonts.
*/
static clearMetrics(font?: string): void;
/**
* Cached canvas element for measuring text
* TODO: this should be private, but isn't because of backward compat, will fix later.
* @ignore
*/
static get _canvas(): ICanvas;
/**
* TODO: this should be private, but isn't because of backward compat, will fix later.
* @ignore
*/
static get _context(): ICanvasRenderingContext2D;
}