Function ansiToPng

src/utils/ansiToPng.ts:91–153

(
  ansiText: string,
  options: AnsiToPngOptions = {},
)

 * Returns a Buffer containing a valid PNG (RGBA, 8-bit).
 */
export function ansiToPng(
  ansiText: string,
  options: AnsiToPngOptions = {},
): Buffer {
  const {
    scale = 1,
    paddingX = 48,
    paddingY = 48,
    borderRadius = 16,
    background = DEFAULT_BG,
  } = options

  const lines = parseAnsi(ansiText)
  // Trim trailing blank lines (same behavior as ansiToSvg).
  while (
    lines.length > 0 &&
    lines[lines.length - 1]!.every(span => span.text.trim() === '')
  ) {
    lines.pop()
  }
  if (lines.length === 0) {
    lines.push([{ text: '', color: background, bold: false }])
  }

  const cols = Math.max(1, ...lines.map(lineWidthCells))
  const rows = lines.length

  const width = (cols * GLYPH_W + paddingX * 2) * scale
  const height = (rows * GLYPH_H + paddingY * 2) * scale

  // RGBA buffer, pre-filled with the background color.
  const px = new Uint8Array(width * height * 4)
  fillBackground(px, background)
  if (borderRadius > 0) {
    roundCorners(px, width, height, borderRadius * scale)
  }

  // Blit glyphs.
  const padX = paddingX * scale
  const padY = paddingY * scale
  for (let row = 0; row < rows; row++) {
    let col = 0
    for (const span of lines[row]!) {
      for (const ch of span.text) {
        const cp = ch.codePointAt(0)!
        const cellW = stringWidth(ch)
        if (cellW === 0) continue // zero-width (combining marks, etc.)
        const x = padX + col * GLYPH_W * scale
        const y = padY + row * GLYPH_H * scale
        const shade = SHADE_ALPHA[cp]
        if (shade !== undefined) {
          blitShade(px, width, x, y, span.color, background, shade, scale)
        } else {
          const glyph = FONT.get(cp) ?? FALLBACK_GLYPH
          blitGlyph(px, width, x, y, glyph, span.color, span.bold, scale)
        }
        col += cellW
      }