PHP利用imagick生成组合缩略图

namespace \clarence\thumbnail;
class Thumbnail extends \Imagick
{
/
 @param array $images
 @param int $width
 @param int $height
 @return static
 @throws ThumbnailException
/
public static function createFromImages($images, $width, $height){
if (empty($images)){
throw new ThumbnailException("No images!");
}
$thumbnail = new static();
$thumbnail->newImage($width, $height, 'white', 'jpg');
$thumbnail->positeImages($images);
return $thumbnail;
}
public function positeImages($images){
$imagesKeys = array_keys($images);
$positeConfig = $this->calcCompositeImagesPosAndSize($images);
foreach ($positeConfig as $index => $cfg){
$imgKey = $imagesKeys[$index];
$img = new \Imagick($images[$imgKey]);
$img = $this->makeCompositeThumbnail($img, $cfg);
$this->positeImage($img, self::COMPOSITE_OVER, $cfg['to']['x'], $cfg['to']['y']);
}
}
protected function makeCompositeThumbnail(\Imagick $img, $cfg){
$img->cropThumbnailImage($cfg['size']['width'], $cfg['size']['height']);
return $img;
}
protected function calcCompositeImagesPosAndSize($images){
$width = $this->getImageWidth();
$height = $this->getImageHeight();
switch(count($images)){
case 0:
throw new ThumbnailException("No images!");
case 1:
// | 0 |
return [
0 => [
'to' => [ 'x' => 0, 'y' => 0 ],
'size' => [
'width' => $width,
'height' => $height,
]
]
];
case 2:
// | 0 | 1 |
return [
0 => [
'to' => [ 'x' => 0, 'y' => 0 ],
'size' => [
'width' => $width / 2,
'height' => $height,
]
],
1 => [
'to' => [ 'x' => $width / 2, 'y' => 0],
'size' => [
'width' => $width / 2,
'height' => $height,
]
]
];
case 3:
// | 0 | 1 |
// | 2 | |
return [
0 => [
'to' => [ 'x' => 0, 'y' => 0 ],
'size' => [
'width' => $width / 2,
'height' => $height / 2,
]
],
1 => [
'to' => [ 'x' => $width / 2, 'y' => 0],
'size' => [
'width' => $width / 2,
'height' => $height,
]
],
2 => [
'to' => [ 'x' => 0, 'y' => $height / 2 ],
'size' => [
'width' => $width / 2,
'height' => $height / 2,
]
],
];
default:
// >= 4:
// | 0 | 1 |
// | 2 | 3 |
return [
0 => [
'to' => [ 'x' => 0, 'y' => 0 ],
'size' => [
'width' => $width / 2,
'height' => $height / 2,
]
],
1 => [
'to' => [ 'x' => $width / 2, 'y' => 0],
'size' => [
'width' => $width / 2,
'height' => $height / 2,
]
],
2 => [
'to' => [ 'x' => 0, 'y' => $height / 2 ],
'size' => [
'width' => $width / 2,
'height' => $height / 2,
]
],
3 => [
'to' => [ 'x' => $width / 2, 'y' => $height / 2],
'size' => [
'width' => $width / 2,
'height' => $height / 2,
]
],
];
}
}
}