imageRaster method

List<int> imageRaster(Image image, { PosAlign align = PosAlign.center, bool highDensityHorizontal = true, bool highDensityVertical = true, PosImageFn imageFn = PosImageFn.bitImageRaster, })

Print an image using (GS v 0) obsolete command

image is an instanse of class from Image library

Implementation

List<int> imageRaster(
  Image image, {
  PosAlign align = PosAlign.center,
  bool highDensityHorizontal = true,
  bool highDensityVertical = true,
  PosImageFn imageFn = PosImageFn.bitImageRaster,
}) {
  List<int> bytes = [];
  // Image alignment
  bytes += setStyles(PosStyles().copyWith(align: align));

  final int widthPx = image.width;
  final int heightPx = image.height;
  final int widthBytes = (widthPx + 7) ~/ 8;
  final List<int> resterizedData = _toRasterFormat(image);

  if (imageFn == PosImageFn.bitImageRaster) {
    // GS v 0
    final int densityByte =
        (highDensityVertical ? 0 : 1) + (highDensityHorizontal ? 0 : 2);

    final List<int> header = List.from(cRasterImg2.codeUnits);
    header.add(densityByte); // m
    header.addAll(_intLowHigh(widthBytes, 2)); // xL xH
    header.addAll(_intLowHigh(heightPx, 2)); // yL yH
    bytes += List.from(header)..addAll(resterizedData);
  } else if (imageFn == PosImageFn.graphics) {
    // 'GS ( L' - FN_112 (Image data)
    final List<int> header1 = List.from(cRasterImg.codeUnits);
    header1.addAll(_intLowHigh(widthBytes * heightPx + 10, 2)); // pL pH
    header1.addAll([48, 112, 48]); // m=48, fn=112, a=48
    header1.addAll([1, 1]); // bx=1, by=1
    header1.addAll([49]); // c=49
    header1.addAll(_intLowHigh(widthBytes, 2)); // xL xH
    header1.addAll(_intLowHigh(heightPx, 2)); // yL yH
    bytes += List.from(header1)..addAll(resterizedData);

    // 'GS ( L' - FN_50 (Run print)
    final List<int> header2 = List.from(cRasterImg.codeUnits);
    header2.addAll([2, 0]); // pL pH
    header2.addAll([48, 50]); // m fn[2,50]
    bytes += List.from(header2);
  }
  return bytes;
}