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shaping.ts
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shaping.ts
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import {
charHasUprightVerticalOrientation,
charAllowsIdeographicBreaking,
charInComplexShapingScript
} from '../util/script_detection';
import verticalizePunctuation from '../util/verticalize_punctuation';
import {plugin as rtlTextPlugin} from '../source/rtl_text_plugin';
import ONE_EM from './one_em';
import {warnOnce} from '../util/util';
import type {StyleGlyph, GlyphMetrics} from '../style/style_glyph';
import {GLYPH_PBF_BORDER} from '../style/parse_glyph_pbf';
import type {ImagePosition} from '../render/image_atlas';
import {IMAGE_PADDING} from '../render/image_atlas';
import type {Rect, GlyphPosition} from '../render/glyph_atlas';
import {Formatted, FormattedSection} from '@maplibre/maplibre-gl-style-spec';
enum WritingMode {
none = 0,
horizontal = 1,
vertical = 2,
horizontalOnly = 3
}
const SHAPING_DEFAULT_OFFSET = -17;
export {shapeText, shapeIcon, fitIconToText, getAnchorAlignment, WritingMode, SHAPING_DEFAULT_OFFSET};
// The position of a glyph relative to the text's anchor point.
export type PositionedGlyph = {
glyph: number;
imageName: string | null;
x: number;
y: number;
vertical: boolean;
scale: number;
fontStack: string;
sectionIndex: number;
metrics: GlyphMetrics;
rect: Rect | null;
};
export type PositionedLine = {
positionedGlyphs: Array<PositionedGlyph>;
lineOffset: number;
};
// A collection of positioned glyphs and some metadata
export type Shaping = {
positionedLines: Array<PositionedLine>;
top: number;
bottom: number;
left: number;
right: number;
writingMode: WritingMode.horizontal | WritingMode.vertical;
text: string;
iconsInText: boolean;
verticalizable: boolean;
};
function isEmpty(positionedLines: Array<PositionedLine>) {
for (const line of positionedLines) {
if (line.positionedGlyphs.length !== 0) {
return false;
}
}
return true;
}
export type SymbolAnchor = 'center' | 'left' | 'right' | 'top' | 'bottom' | 'top-left' | 'top-right' | 'bottom-left' | 'bottom-right';
export type TextJustify = 'left' | 'center' | 'right';
// Max number of images in label is 6401 U+E000–U+F8FF that covers
// Basic Multilingual Plane Unicode Private Use Area (PUA).
const PUAbegin = 0xE000;
const PUAend = 0xF8FF;
class SectionOptions {
// Text options
scale: number;
fontStack: string;
// Image options
imageName: string | null;
constructor() {
this.scale = 1.0;
this.fontStack = '';
this.imageName = null;
}
static forText(scale: number | null, fontStack: string) {
const textOptions = new SectionOptions();
textOptions.scale = scale || 1;
textOptions.fontStack = fontStack;
return textOptions;
}
static forImage(imageName: string) {
const imageOptions = new SectionOptions();
imageOptions.imageName = imageName;
return imageOptions;
}
}
class TaggedString {
text: string;
sectionIndex: Array<number>; // maps each character in 'text' to its corresponding entry in 'sections'
sections: Array<SectionOptions>;
imageSectionID: number | null;
constructor() {
this.text = '';
this.sectionIndex = [];
this.sections = [];
this.imageSectionID = null;
}
static fromFeature(text: Formatted, defaultFontStack: string) {
const result = new TaggedString();
for (let i = 0; i < text.sections.length; i++) {
const section = text.sections[i];
if (!section.image) {
result.addTextSection(section, defaultFontStack);
} else {
result.addImageSection(section);
}
}
return result;
}
length(): number {
return this.text.length;
}
getSection(index: number): SectionOptions {
return this.sections[this.sectionIndex[index]];
}
getSectionIndex(index: number): number {
return this.sectionIndex[index];
}
getCharCode(index: number): number {
return this.text.charCodeAt(index);
}
verticalizePunctuation() {
this.text = verticalizePunctuation(this.text);
}
trim() {
let beginningWhitespace = 0;
for (let i = 0;
i < this.text.length && whitespace[this.text.charCodeAt(i)];
i++) {
beginningWhitespace++;
}
let trailingWhitespace = this.text.length;
for (let i = this.text.length - 1;
i >= 0 && i >= beginningWhitespace && whitespace[this.text.charCodeAt(i)];
i--) {
trailingWhitespace--;
}
this.text = this.text.substring(beginningWhitespace, trailingWhitespace);
this.sectionIndex = this.sectionIndex.slice(beginningWhitespace, trailingWhitespace);
}
substring(start: number, end: number): TaggedString {
const substring = new TaggedString();
substring.text = this.text.substring(start, end);
substring.sectionIndex = this.sectionIndex.slice(start, end);
substring.sections = this.sections;
return substring;
}
toString(): string {
return this.text;
}
getMaxScale() {
return this.sectionIndex.reduce((max, index) => Math.max(max, this.sections[index].scale), 0);
}
addTextSection(section: FormattedSection, defaultFontStack: string) {
this.text += section.text;
this.sections.push(SectionOptions.forText(section.scale, section.fontStack || defaultFontStack));
const index = this.sections.length - 1;
for (let i = 0; i < section.text.length; ++i) {
this.sectionIndex.push(index);
}
}
addImageSection(section: FormattedSection) {
const imageName = section.image ? section.image.name : '';
if (imageName.length === 0) {
warnOnce('Can\'t add FormattedSection with an empty image.');
return;
}
const nextImageSectionCharCode = this.getNextImageSectionCharCode();
if (!nextImageSectionCharCode) {
warnOnce(`Reached maximum number of images ${PUAend - PUAbegin + 2}`);
return;
}
this.text += String.fromCharCode(nextImageSectionCharCode);
this.sections.push(SectionOptions.forImage(imageName));
this.sectionIndex.push(this.sections.length - 1);
}
getNextImageSectionCharCode(): number | null {
if (!this.imageSectionID) {
this.imageSectionID = PUAbegin;
return this.imageSectionID;
}
if (this.imageSectionID >= PUAend) return null;
return ++this.imageSectionID;
}
}
function breakLines(input: TaggedString, lineBreakPoints: Array<number>): Array<TaggedString> {
const lines = [];
const text = input.text;
let start = 0;
for (const lineBreak of lineBreakPoints) {
lines.push(input.substring(start, lineBreak));
start = lineBreak;
}
if (start < text.length) {
lines.push(input.substring(start, text.length));
}
return lines;
}
function shapeText(
text: Formatted,
glyphMap: {
[_: string]: {
[_: number]: StyleGlyph;
};
},
glyphPositions: {
[_: string]: {
[_: number]: GlyphPosition;
};
},
imagePositions: {[_: string]: ImagePosition},
defaultFontStack: string,
maxWidth: number,
lineHeight: number,
textAnchor: SymbolAnchor,
textJustify: TextJustify,
spacing: number,
translate: [number, number],
writingMode: WritingMode.horizontal | WritingMode.vertical,
allowVerticalPlacement: boolean,
symbolPlacement: string,
layoutTextSize: number,
layoutTextSizeThisZoom: number
): Shaping | false {
const logicalInput = TaggedString.fromFeature(text, defaultFontStack);
if (writingMode === WritingMode.vertical) {
logicalInput.verticalizePunctuation();
}
let lines: Array<TaggedString>;
const {processBidirectionalText, processStyledBidirectionalText} = rtlTextPlugin;
if (processBidirectionalText && logicalInput.sections.length === 1) {
// Bidi doesn't have to be style-aware
lines = [];
const untaggedLines =
processBidirectionalText(logicalInput.toString(),
determineLineBreaks(logicalInput, spacing, maxWidth, glyphMap, imagePositions, symbolPlacement, layoutTextSize));
for (const line of untaggedLines) {
const taggedLine = new TaggedString();
taggedLine.text = line;
taggedLine.sections = logicalInput.sections;
for (let i = 0; i < line.length; i++) {
taggedLine.sectionIndex.push(0);
}
lines.push(taggedLine);
}
} else if (processStyledBidirectionalText) {
// Need version of mapbox-gl-rtl-text with style support for combining RTL text
// with formatting
lines = [];
const processedLines =
processStyledBidirectionalText(logicalInput.text,
logicalInput.sectionIndex,
determineLineBreaks(logicalInput, spacing, maxWidth, glyphMap, imagePositions, symbolPlacement, layoutTextSize));
for (const line of processedLines) {
const taggedLine = new TaggedString();
taggedLine.text = line[0];
taggedLine.sectionIndex = line[1];
taggedLine.sections = logicalInput.sections;
lines.push(taggedLine);
}
} else {
lines = breakLines(logicalInput, determineLineBreaks(logicalInput, spacing, maxWidth, glyphMap, imagePositions, symbolPlacement, layoutTextSize));
}
const positionedLines = [];
const shaping = {
positionedLines,
text: logicalInput.toString(),
top: translate[1],
bottom: translate[1],
left: translate[0],
right: translate[0],
writingMode,
iconsInText: false,
verticalizable: false
};
shapeLines(shaping, glyphMap, glyphPositions, imagePositions, lines, lineHeight, textAnchor, textJustify, writingMode, spacing, allowVerticalPlacement, layoutTextSizeThisZoom);
if (isEmpty(positionedLines)) return false;
return shaping;
}
// using computed properties due to https://github.com/facebook/flow/issues/380
/* eslint no-useless-computed-key: 0 */
const whitespace: {
[_: number]: boolean;
} = {
[0x09]: true, // tab
[0x0a]: true, // newline
[0x0b]: true, // vertical tab
[0x0c]: true, // form feed
[0x0d]: true, // carriage return
[0x20]: true, // space
};
const breakable: {
[_: number]: boolean;
} = {
[0x0a]: true, // newline
[0x20]: true, // space
[0x26]: true, // ampersand
[0x28]: true, // left parenthesis
[0x29]: true, // right parenthesis
[0x2b]: true, // plus sign
[0x2d]: true, // hyphen-minus
[0x2f]: true, // solidus
[0xad]: true, // soft hyphen
[0xb7]: true, // middle dot
[0x200b]: true, // zero-width space
[0x2010]: true, // hyphen
[0x2013]: true, // en dash
[0x2027]: true // interpunct
// Many other characters may be reasonable breakpoints
// Consider "neutral orientation" characters at scriptDetection.charHasNeutralVerticalOrientation
// See https://github.com/mapbox/mapbox-gl-js/issues/3658
};
function getGlyphAdvance(
codePoint: number,
section: SectionOptions,
glyphMap: {
[_: string]: {
[_: number]: StyleGlyph;
};
},
imagePositions: {[_: string]: ImagePosition},
spacing: number,
layoutTextSize: number
): number {
if (!section.imageName) {
const positions = glyphMap[section.fontStack];
const glyph = positions && positions[codePoint];
if (!glyph) return 0;
return glyph.metrics.advance * section.scale + spacing;
} else {
const imagePosition = imagePositions[section.imageName];
if (!imagePosition) return 0;
return imagePosition.displaySize[0] * section.scale * ONE_EM / layoutTextSize + spacing;
}
}
function determineAverageLineWidth(logicalInput: TaggedString,
spacing: number,
maxWidth: number,
glyphMap: {
[_: string]: {
[_: number]: StyleGlyph;
};
},
imagePositions: {[_: string]: ImagePosition},
layoutTextSize: number) {
let totalWidth = 0;
for (let index = 0; index < logicalInput.length(); index++) {
const section = logicalInput.getSection(index);
totalWidth += getGlyphAdvance(logicalInput.getCharCode(index), section, glyphMap, imagePositions, spacing, layoutTextSize);
}
const lineCount = Math.max(1, Math.ceil(totalWidth / maxWidth));
return totalWidth / lineCount;
}
function calculateBadness(lineWidth: number,
targetWidth: number,
penalty: number,
isLastBreak: boolean) {
const raggedness = Math.pow(lineWidth - targetWidth, 2);
if (isLastBreak) {
// Favor finals lines shorter than average over longer than average
if (lineWidth < targetWidth) {
return raggedness / 2;
} else {
return raggedness * 2;
}
}
return raggedness + Math.abs(penalty) * penalty;
}
function calculatePenalty(codePoint: number, nextCodePoint: number, penalizableIdeographicBreak: boolean) {
let penalty = 0;
// Force break on newline
if (codePoint === 0x0a) {
penalty -= 10000;
}
// Penalize breaks between characters that allow ideographic breaking because
// they are less preferable than breaks at spaces (or zero width spaces).
if (penalizableIdeographicBreak) {
penalty += 150;
}
// Penalize open parenthesis at end of line
if (codePoint === 0x28 || codePoint === 0xff08) {
penalty += 50;
}
// Penalize close parenthesis at beginning of line
if (nextCodePoint === 0x29 || nextCodePoint === 0xff09) {
penalty += 50;
}
return penalty;
}
type Break = {
index: number;
x: number;
priorBreak: Break;
badness: number;
};
function evaluateBreak(
breakIndex: number,
breakX: number,
targetWidth: number,
potentialBreaks: Array<Break>,
penalty: number,
isLastBreak: boolean
): Break {
// We could skip evaluating breaks where the line length (breakX - priorBreak.x) > maxWidth
// ...but in fact we allow lines longer than maxWidth (if there's no break points)
// ...and when targetWidth and maxWidth are close, strictly enforcing maxWidth can give
// more lopsided results.
let bestPriorBreak: Break = null;
let bestBreakBadness = calculateBadness(breakX, targetWidth, penalty, isLastBreak);
for (const potentialBreak of potentialBreaks) {
const lineWidth = breakX - potentialBreak.x;
const breakBadness =
calculateBadness(lineWidth, targetWidth, penalty, isLastBreak) + potentialBreak.badness;
if (breakBadness <= bestBreakBadness) {
bestPriorBreak = potentialBreak;
bestBreakBadness = breakBadness;
}
}
return {
index: breakIndex,
x: breakX,
priorBreak: bestPriorBreak,
badness: bestBreakBadness
};
}
function leastBadBreaks(lastLineBreak?: Break | null): Array<number> {
if (!lastLineBreak) {
return [];
}
return leastBadBreaks(lastLineBreak.priorBreak).concat(lastLineBreak.index);
}
function determineLineBreaks(
logicalInput: TaggedString,
spacing: number,
maxWidth: number,
glyphMap: {
[_: string]: {
[_: number]: StyleGlyph;
};
},
imagePositions: {[_: string]: ImagePosition},
symbolPlacement: string,
layoutTextSize: number
): Array<number> {
if (symbolPlacement !== 'point')
return [];
if (!logicalInput)
return [];
const potentialLineBreaks = [];
const targetWidth = determineAverageLineWidth(logicalInput, spacing, maxWidth, glyphMap, imagePositions, layoutTextSize);
const hasServerSuggestedBreakpoints = logicalInput.text.indexOf('\u200b') >= 0;
let currentX = 0;
for (let i = 0; i < logicalInput.length(); i++) {
const section = logicalInput.getSection(i);
const codePoint = logicalInput.getCharCode(i);
if (!whitespace[codePoint]) currentX += getGlyphAdvance(codePoint, section, glyphMap, imagePositions, spacing, layoutTextSize);
// Ideographic characters, spaces, and word-breaking punctuation that often appear without
// surrounding spaces.
if ((i < logicalInput.length() - 1)) {
const ideographicBreak = charAllowsIdeographicBreaking(codePoint);
if (breakable[codePoint] || ideographicBreak || section.imageName) {
potentialLineBreaks.push(
evaluateBreak(
i + 1,
currentX,
targetWidth,
potentialLineBreaks,
calculatePenalty(codePoint, logicalInput.getCharCode(i + 1), ideographicBreak && hasServerSuggestedBreakpoints),
false));
}
}
}
return leastBadBreaks(
evaluateBreak(
logicalInput.length(),
currentX,
targetWidth,
potentialLineBreaks,
0,
true));
}
function getAnchorAlignment(anchor: SymbolAnchor) {
let horizontalAlign = 0.5, verticalAlign = 0.5;
switch (anchor) {
case 'right':
case 'top-right':
case 'bottom-right':
horizontalAlign = 1;
break;
case 'left':
case 'top-left':
case 'bottom-left':
horizontalAlign = 0;
break;
}
switch (anchor) {
case 'bottom':
case 'bottom-right':
case 'bottom-left':
verticalAlign = 1;
break;
case 'top':
case 'top-right':
case 'top-left':
verticalAlign = 0;
break;
}
return {horizontalAlign, verticalAlign};
}
function shapeLines(shaping: Shaping,
glyphMap: {
[_: string]: {
[_: number]: StyleGlyph;
};
},
glyphPositions: {
[_: string]: {
[_: number]: GlyphPosition;
};
},
imagePositions: {[_: string]: ImagePosition},
lines: Array<TaggedString>,
lineHeight: number,
textAnchor: SymbolAnchor,
textJustify: TextJustify,
writingMode: WritingMode.horizontal | WritingMode.vertical,
spacing: number,
allowVerticalPlacement: boolean,
layoutTextSizeThisZoom: number) {
let x = 0;
let y = SHAPING_DEFAULT_OFFSET;
let maxLineLength = 0;
let maxLineHeight = 0;
const justify =
textJustify === 'right' ? 1 :
textJustify === 'left' ? 0 : 0.5;
let lineIndex = 0;
for (const line of lines) {
line.trim();
const lineMaxScale = line.getMaxScale();
const maxLineOffset = (lineMaxScale - 1) * ONE_EM;
const positionedLine = {positionedGlyphs: [], lineOffset: 0};
shaping.positionedLines[lineIndex] = positionedLine;
const positionedGlyphs = positionedLine.positionedGlyphs;
let lineOffset = 0.0;
if (!line.length()) {
y += lineHeight; // Still need a line feed after empty line
++lineIndex;
continue;
}
for (let i = 0; i < line.length(); i++) {
const section = line.getSection(i);
const sectionIndex = line.getSectionIndex(i);
const codePoint = line.getCharCode(i);
let baselineOffset = 0.0;
let metrics = null;
let rect = null;
let imageName = null;
let verticalAdvance = ONE_EM;
const vertical = !(writingMode === WritingMode.horizontal ||
// Don't verticalize glyphs that have no upright orientation if vertical placement is disabled.
(!allowVerticalPlacement && !charHasUprightVerticalOrientation(codePoint)) ||
// If vertical placement is enabled, don't verticalize glyphs that
// are from complex text layout script, or whitespaces.
(allowVerticalPlacement && (whitespace[codePoint] || charInComplexShapingScript(codePoint))));
if (!section.imageName) {
const positions = glyphPositions[section.fontStack];
const glyphPosition = positions && positions[codePoint];
if (glyphPosition && glyphPosition.rect) {
rect = glyphPosition.rect;
metrics = glyphPosition.metrics;
} else {
const glyphs = glyphMap[section.fontStack];
const glyph = glyphs && glyphs[codePoint];
if (!glyph) continue;
metrics = glyph.metrics;
}
// We don't know the baseline, but since we're laying out
// at 24 points, we can calculate how much it will move when
// we scale up or down.
baselineOffset = (lineMaxScale - section.scale) * ONE_EM;
} else {
const imagePosition = imagePositions[section.imageName];
if (!imagePosition) continue;
imageName = section.imageName;
shaping.iconsInText = shaping.iconsInText || true;
rect = imagePosition.paddedRect;
const size = imagePosition.displaySize;
// If needed, allow to set scale factor for an image using
// alias "image-scale" that could be alias for "font-scale"
// when FormattedSection is an image section.
section.scale = section.scale * ONE_EM / layoutTextSizeThisZoom;
metrics = {width: size[0],
height: size[1],
left: IMAGE_PADDING,
top: -GLYPH_PBF_BORDER,
advance: vertical ? size[1] : size[0]};
// Difference between one EM and an image size.
// Aligns bottom of an image to a baseline level.
const imageOffset = ONE_EM - size[1] * section.scale;
baselineOffset = maxLineOffset + imageOffset;
verticalAdvance = metrics.advance;
// Difference between height of an image and one EM at max line scale.
// Pushes current line down if an image size is over 1 EM at max line scale.
const offset = vertical ? size[0] * section.scale - ONE_EM * lineMaxScale :
size[1] * section.scale - ONE_EM * lineMaxScale;
if (offset > 0 && offset > lineOffset) {
lineOffset = offset;
}
}
if (!vertical) {
positionedGlyphs.push({glyph: codePoint, imageName, x, y: y + baselineOffset, vertical, scale: section.scale, fontStack: section.fontStack, sectionIndex, metrics, rect});
x += metrics.advance * section.scale + spacing;
} else {
shaping.verticalizable = true;
positionedGlyphs.push({glyph: codePoint, imageName, x, y: y + baselineOffset, vertical, scale: section.scale, fontStack: section.fontStack, sectionIndex, metrics, rect});
x += verticalAdvance * section.scale + spacing;
}
}
// Only justify if we placed at least one glyph
if (positionedGlyphs.length !== 0) {
const lineLength = x - spacing;
maxLineLength = Math.max(lineLength, maxLineLength);
justifyLine(positionedGlyphs, 0, positionedGlyphs.length - 1, justify, lineOffset);
}
x = 0;
const currentLineHeight = lineHeight * lineMaxScale + lineOffset;
positionedLine.lineOffset = Math.max(lineOffset, maxLineOffset);
y += currentLineHeight;
maxLineHeight = Math.max(currentLineHeight, maxLineHeight);
++lineIndex;
}
// Calculate the bounding box and justify / align text block.
const height = y - SHAPING_DEFAULT_OFFSET;
const {horizontalAlign, verticalAlign} = getAnchorAlignment(textAnchor);
align(shaping.positionedLines, justify, horizontalAlign, verticalAlign, maxLineLength, maxLineHeight, lineHeight, height, lines.length);
shaping.top += -verticalAlign * height;
shaping.bottom = shaping.top + height;
shaping.left += -horizontalAlign * maxLineLength;
shaping.right = shaping.left + maxLineLength;
}
// justify right = 1, left = 0, center = 0.5
function justifyLine(positionedGlyphs: Array<PositionedGlyph>,
start: number,
end: number,
justify: 1 | 0 | 0.5,
lineOffset: number) {
if (!justify && !lineOffset)
return;
const lastPositionedGlyph = positionedGlyphs[end];
const lastAdvance = lastPositionedGlyph.metrics.advance * lastPositionedGlyph.scale;
const lineIndent = (positionedGlyphs[end].x + lastAdvance) * justify;
for (let j = start; j <= end; j++) {
positionedGlyphs[j].x -= lineIndent;
positionedGlyphs[j].y += lineOffset;
}
}
function align(positionedLines: Array<PositionedLine>,
justify: number,
horizontalAlign: number,
verticalAlign: number,
maxLineLength: number,
maxLineHeight: number,
lineHeight: number,
blockHeight: number,
lineCount: number) {
const shiftX = (justify - horizontalAlign) * maxLineLength;
let shiftY = 0;
if (maxLineHeight !== lineHeight) {
shiftY = -blockHeight * verticalAlign - SHAPING_DEFAULT_OFFSET;
} else {
shiftY = (-verticalAlign * lineCount + 0.5) * lineHeight;
}
for (const line of positionedLines) {
for (const positionedGlyph of line.positionedGlyphs) {
positionedGlyph.x += shiftX;
positionedGlyph.y += shiftY;
}
}
}
export type PositionedIcon = {
image: ImagePosition;
top: number;
bottom: number;
left: number;
right: number;
collisionPadding?: [number, number, number, number];
};
function shapeIcon(
image: ImagePosition,
iconOffset: [number, number],
iconAnchor: SymbolAnchor
): PositionedIcon {
const {horizontalAlign, verticalAlign} = getAnchorAlignment(iconAnchor);
const dx = iconOffset[0];
const dy = iconOffset[1];
const x1 = dx - image.displaySize[0] * horizontalAlign;
const x2 = x1 + image.displaySize[0];
const y1 = dy - image.displaySize[1] * verticalAlign;
const y2 = y1 + image.displaySize[1];
return {image, top: y1, bottom: y2, left: x1, right: x2};
}
function fitIconToText(
shapedIcon: PositionedIcon,
shapedText: Shaping,
textFit: string,
padding: [number, number, number, number],
iconOffset: [number, number],
fontScale: number
): PositionedIcon {
const image = shapedIcon.image;
let collisionPadding;
if (image.content) {
const content = image.content;
const pixelRatio = image.pixelRatio || 1;
collisionPadding = [
content[0] / pixelRatio,
content[1] / pixelRatio,
image.displaySize[0] - content[2] / pixelRatio,
image.displaySize[1] - content[3] / pixelRatio
];
}
// We don't respect the icon-anchor, because icon-text-fit is set. Instead,
// the icon will be centered on the text, then stretched in the given
// dimensions.
const textLeft = shapedText.left * fontScale;
const textRight = shapedText.right * fontScale;
let top, right, bottom, left;
if (textFit === 'width' || textFit === 'both') {
// Stretched horizontally to the text width
left = iconOffset[0] + textLeft - padding[3];
right = iconOffset[0] + textRight + padding[1];
} else {
// Centered on the text
left = iconOffset[0] + (textLeft + textRight - image.displaySize[0]) / 2;
right = left + image.displaySize[0];
}
const textTop = shapedText.top * fontScale;
const textBottom = shapedText.bottom * fontScale;
if (textFit === 'height' || textFit === 'both') {
// Stretched vertically to the text height
top = iconOffset[1] + textTop - padding[0];
bottom = iconOffset[1] + textBottom + padding[2];
} else {
// Centered on the text
top = iconOffset[1] + (textTop + textBottom - image.displaySize[1]) / 2;
bottom = top + image.displaySize[1];
}
return {image, top, right, bottom, left, collisionPadding};
}