Output the image in column format.
| public toColumnFormat ( boolean $doubleDensity = false ) : string[] | ||
| $doubleDensity | boolean | True for double density (24px) lines, false for single-density (8px) lines. |
| return | string[] | an array, one item per line of output. All lines will be of equal size. |
/**
* Print an image, using the older "bit image" command in column format.
*
* Should only be used if your printer does not support the graphics() or
* bitImage() commands.
*
* @param EscposImage $img The image to print
* @param int $size Size modifier for the image. Must be either `Printer::IMG_DEFAULT`
* (default), or any combination of the `Printer::IMG_DOUBLE_HEIGHT` and
* `Printer::IMG_DOUBLE_WIDTH` flags.
*/
public function bitImageColumnFormat(EscposImage $img, $size = Printer::IMG_DEFAULT)
{
$highDensityVertical = !(($size & self::IMG_DOUBLE_HEIGHT) == Printer::IMG_DOUBLE_HEIGHT);
$highDensityHorizontal = !(($size & self::IMG_DOUBLE_WIDTH) == Printer::IMG_DOUBLE_WIDTH);
// Experimental column format printing
// This feature is not yet complete and may produce unpredictable results.
$this->setLineSpacing(16);
// 16-dot line spacing. This is the correct value on both TM-T20 and TM-U220
// Header and density code (0, 1, 32, 33) re-used for every line
$densityCode = ($highDensityHorizontal ? 1 : 0) + ($highDensityVertical ? 32 : 0);
$colFormatData = $img->toColumnFormat($highDensityVertical);
$header = Printer::dataHeader(array($img->getWidth()), true);
foreach ($colFormatData as $line) {
// Print each line, double density etc for printing are set here also
$this->connector->write(self::ESC . "*" . chr($densityCode) . $header . $line);
$this->feed();
// sleep(0.1); // Reduces the amount of trouble that a TM-U220 has keeping up with large images
}
$this->setLineSpacing();
// Revert to default line spacing
}