if ($stop < ($i + 1) * (M_PI / 2) && $y <= $yStop) {
                        $diffColor1 = imagecolorexactalpha($img, $color[0], $color[1], $color[2], 127 - (127 - $color[3]) * $error1);
                        $x1         = $_x1;
                        if (!$aaStopX) {
                            imagesetpixel($img, $cx + $xp * ($x1 - 1) + $xa, $cy + $yp * ($y) + $ya, $diffColor1);