/**
* A fast method to retrieve one row of data from the matrix as a BitArray.
*
* @param $y; The row to retrieve
* @param $row; An optional caller-allocated BitArray, will be allocated if null or too small
* @return The resulting BitArray - this reference should always be used even when passing
* your own row
*/
public function getRow($y, $row)
{
if ($row == null || $row->getSize() < $this->width) {
$row = new BitArray($this->width);
} else {
$row->clear();
}
$offset = $y * $this->rowSize;
for ($x = 0; $x < $this->rowSize; $x++) {
$row->setBulk($x * 32, $this->bits[$offset + $x]);
}
return $row;
}
