nothoughts/node_modules/pixi.js/lib/scene/text-bitmap/utils/getBitmapTextLayout.js

'use strict';

"use strict";
function getBitmapTextLayout(chars, style, font, trimEnd) {
  const layoutData = {
    width: 0,
    height: 0,
    offsetY: 0,
    scale: style.fontSize / font.baseMeasurementFontSize,
    lines: [{
      width: 0,
      charPositions: [],
      spaceWidth: 0,
      spacesIndex: [],
      chars: []
    }]
  };
  layoutData.offsetY = font.baseLineOffset;
  let currentLine = layoutData.lines[0];
  let previousChar = null;
  let firstWord = true;
  const currentWord = {
    spaceWord: false,
    width: 0,
    start: 0,
    index: 0,
    // use index to not modify the array as we use it a lot!
    positions: [],
    chars: []
  };
  const nextWord = (word) => {
    const start = currentLine.width;
    for (let j = 0; j < currentWord.index; j++) {
      const position = word.positions[j];
      currentLine.chars.push(word.chars[j]);
      currentLine.charPositions.push(position + start);
    }
    currentLine.width += word.width;
    firstWord = false;
    currentWord.width = 0;
    currentWord.index = 0;
    currentWord.chars.length = 0;
  };
  const nextLine = () => {
    let index = currentLine.chars.length - 1;
    if (trimEnd) {
      let lastChar = currentLine.chars[index];
      while (lastChar === " ") {
        currentLine.width -= font.chars[lastChar].xAdvance;
        lastChar = currentLine.chars[--index];
      }
    }
    layoutData.width = Math.max(layoutData.width, currentLine.width);
    currentLine = {
      width: 0,
      charPositions: [],
      chars: [],
      spaceWidth: 0,
      spacesIndex: []
    };
    firstWord = true;
    layoutData.lines.push(currentLine);
    layoutData.height += font.lineHeight;
  };
  const scale = font.baseMeasurementFontSize / style.fontSize;
  const adjustedLetterSpacing = style.letterSpacing * scale;
  const adjustedWordWrapWidth = style.wordWrapWidth * scale;
  for (let i = 0; i < chars.length + 1; i++) {
    let char;
    const isEnd = i === chars.length;
    if (!isEnd) {
      char = chars[i];
    }
    const charData = font.chars[char] || font.chars[" "];
    const isSpace = /(?:\s)/.test(char);
    const isWordBreak = isSpace || char === "\r" || char === "\n" || isEnd;
    if (isWordBreak) {
      const addWordToNextLine = !firstWord && style.wordWrap && currentLine.width + currentWord.width - adjustedLetterSpacing > adjustedWordWrapWidth;
      if (addWordToNextLine) {
        nextLine();
        nextWord(currentWord);
        if (!isEnd) {
          currentLine.charPositions.push(0);
        }
      } else {
        currentWord.start = currentLine.width;
        nextWord(currentWord);
        if (!isEnd) {
          currentLine.charPositions.push(0);
        }
      }
      if (char === "\r" || char === "\n") {
        if (currentLine.width !== 0) {
          nextLine();
        }
      } else if (!isEnd) {
        const spaceWidth = charData.xAdvance + (charData.kerning[previousChar] || 0) + adjustedLetterSpacing;
        currentLine.width += spaceWidth;
        currentLine.spaceWidth = spaceWidth;
        currentLine.spacesIndex.push(currentLine.charPositions.length);
        currentLine.chars.push(char);
      }
    } else {
      const kerning = charData.kerning[previousChar] || 0;
      const nextCharWidth = charData.xAdvance + kerning + adjustedLetterSpacing;
      currentWord.positions[currentWord.index++] = currentWord.width + kerning;
      currentWord.chars.push(char);
      currentWord.width += nextCharWidth;
    }
    previousChar = char;
  }
  nextLine();
  if (style.align === "center") {
    alignCenter(layoutData);
  } else if (style.align === "right") {
    alignRight(layoutData);
  } else if (style.align === "justify") {
    alignJustify(layoutData);
  }
  return layoutData;
}
function alignCenter(measurementData) {
  for (let i = 0; i < measurementData.lines.length; i++) {
    const line = measurementData.lines[i];
    const offset = measurementData.width / 2 - line.width / 2;
    for (let j = 0; j < line.charPositions.length; j++) {
      line.charPositions[j] += offset;
    }
  }
}
function alignRight(measurementData) {
  for (let i = 0; i < measurementData.lines.length; i++) {
    const line = measurementData.lines[i];
    const offset = measurementData.width - line.width;
    for (let j = 0; j < line.charPositions.length; j++) {
      line.charPositions[j] += offset;
    }
  }
}
function alignJustify(measurementData) {
  const width = measurementData.width;
  for (let i = 0; i < measurementData.lines.length; i++) {
    const line = measurementData.lines[i];
    let indy = 0;
    let spaceIndex = line.spacesIndex[indy++];
    let offset = 0;
    const totalSpaces = line.spacesIndex.length;
    const newSpaceWidth = (width - line.width) / totalSpaces;
    const spaceWidth = newSpaceWidth;
    for (let j = 0; j < line.charPositions.length; j++) {
      if (j === spaceIndex) {
        spaceIndex = line.spacesIndex[indy++];
        offset += spaceWidth;
      }
      line.charPositions[j] += offset;
    }
  }
}

exports.getBitmapTextLayout = getBitmapTextLayout;
//# sourceMappingURL=getBitmapTextLayout.js.map