Finding cells within range on a hexagonal grid

Question

I'm looking for a way to get the cells based on a N range. But no luck.

I'm converting Row Column offset to Cube Coordinate system QR -> XYZ

$range = 1;
for ($dx = -$range; $dx <= $range; $dx++)
{
    for ($dy = max(-$range, -$dx - $range); $dy <= min($range, -$dx + $range); $dy++)
    {
        $dz = -$dx-$dy;
        $points = $hexagon->cube_to_oddq(array($dx,$dy,$dz));
        $x = $hexagon->ver + $points[0] * $hexagon->size * 1.5;
        $y = $hexagon->height + $points[1] * $hexagon->height + ( ($points[0]%2) * ( $hexagon->height / 2 ) ); 
        $points = $hexagon->drawHex($x,$y, true);
        $pointss = array();
        foreach($points as $p) {
            $pointss[] = $p[0];
            $pointss[] = $p[1];
        }
        imagefilledpolygon ( $png_image , $pointss , 6 , $black );
    }
}

Result: Inside every hex cell (First line is QR coordinate) (Second line is XYZ converted coordinate)

Any advice what I'm doing wrong?

Update:

As requested, the Oddq (Q,R) to Cube conversion XYZ

    $i = $hex[0] = ROW
    $j = $hex[2] = COLUMN
    public function oddq_to_cube($hex){
        $hex[2] = $hex[1];
        $x = $hex[2];
        $z = $hex[0] - ($hex[2] - ($hex[2]&1)) / 2;
        $y = -$x-$z;
        return array($x, $y, $z);
    }
    $curr_cube = $hexagon->oddq_to_cube(array($i,$j));

Answer 1

I think you have the "offset-q" coordinate system mixed up with the cubical coordinate system. In general, it's easier to translate from the cubical coordinates to screen coordinates because it's a simple linear transformation.

for ($dx = -$range; $dx <= $range; $dx++)
{
    for ($dy = max(-$range, -$dx - $range); $dy <= min($range, -$dx + $range); $dy++)
    {
        $x = 96 + $hexagon->ver + $hexagon->size * 1.5 * $dx;
        $y = 54.6 + $hexagon->height + $hexagon->height * $dy + $hexagon->height/2 * $dx;
        $points = $hexagon->drawHex($x,$y, true);
        ...