public function flip($iMode)
{
$iWidth = $this->getWidth();
$iHeight = $this->getHeight();
$src_x = 0;
$src_y = 0;
$src_width = $iWidth;
$src_height = $iHeight;
switch ($iMode) {
case 1:
//vertical
$src_y = $iHeight - 1;
$src_height = -$iHeight;
break;
case 2:
//horizontal
$src_x = $iWidth - 1;
$src_width = -$iWidth;
break;
case 3:
//both
$src_x = $iWidth - 1;
$src_y = $iHeight - 1;
$src_width = -$iWidth;
$src_height = -$iHeight;
break;
default:
return;
}
$imgdest = new GDImage($iWidth, $iHeight);
$imgdest->setAntiAlias($this->isAntiAlias());
$imgdest->setAlphaBlending($this->isAlphaBlending());
$imgdest->set8BitAlpha($this->is8BitAlpha());
$imgdest->copyResampled($this, 0, 0, $src_x, $src_y, $iWidth, $iHeight, $src_width, $src_height);
$this->replace($imgdest);
}