GDToolkitReflect.php in ImageCache Reflect 8
File
lib/Drupal/imagecache_reflect/Plugin/ImageToolkit/GDToolkitReflect.phpView source
<?php
/**
* @file
* Contains \Drupal\imagecache_reflect\Plugin\ImageToolkit\GDToolkitReflect.
*/
namespace Drupal\imagecache_reflect\Plugin\ImageToolkit;
use Drupal\Core\Image\ImageInterface;
/**
* Creates a reflect operation for the GD library.
*
* @todo Register this class as a GDToolkit operation plugin.
*/
class GDToolkitReflect {
/**
* Creates an image with a reflection-like effect from a provided image.
*
* @param resource $image
* The image object to create the reflected image from.
* @param array $configuration
* An associative array containing:
* -color: Hex color of the reflection background.
* -transparency: Boolean. Whether to preserve alpha transparency.
* -position: Reflection position (left, right, top, bottom).
* -size: Size of the reflection in percent or pixels.
*
* @return bool
* Returns TRUE if successful.
*/
public static function reflect(ImageInterface $image, array $configuration) {
// Verify that Drupal is using the PHP GD library for image manipulations
// since this effect depends on functions in the GD library.
if ($image
->getToolkitId() != 'gd') {
watchdog('image', 'Image reflect failed on %path. Using non GD toolkit.', array(
'%path' => $image
->getSource(),
), WATCHDOG_ERROR);
return FALSE;
}
// Get config params.
$color = $configuration['bgcolor'];
$transparency = $configuration['transparency'];
$position = $configuration['position'];
$size = $configuration['size'];
// Image source for the reflection effect.
$src_im = $image
->getResource();
// Expand the canvas vertically or horizontally depending on
// the reflection position.
$is_vertical = \in_array($position, array(
'top',
'bottom',
));
// Determine the reflection size in pixels.
// Calculate pixels from a percentage if given.
if (preg_match('/^\\d{1,3}%$/', $size)) {
$image_size = $is_vertical ? $image
->getHeight() : $image
->getWidth();
$size = $image_size * (floatval($size) / 100);
}
else {
$size = intval($size);
}
// Calculate the final dimensions of the image with its reflection.
$width = $image
->getWidth() + ($is_vertical ? 0 : $size);
$height = $image
->getHeight() + ($is_vertical ? $size : 0);
// Creates a new destination canvas.
$dst_im = imagecreatetruecolor($width, $height);
// If $color is empty, we're trying for a transparent canvas:
if (empty($color)) {
imagesavealpha($dst_im, TRUE);
imagealphablending($dst_im, FALSE);
}
else {
// Convert short #FFF syntax to full #FFFFFF syntax.
if (strlen($color) == 4) {
$c = $color;
$color = $c[0] . $c[1] . $c[1] . $c[2] . $c[2] . $c[3] . $c[3];
}
// Convert #FFFFFF syntax to hexadecimal colors.
$color = hexdec(str_replace('#', '0x', $color));
imagefill($dst_im, 0, 0, $color);
}
// Determine x,y coordinates where source will be on the new image canvas.
$x = $position == 'left' ? $size : 0;
$y = $position == 'top' ? $size : 0;
// Copy the source image onto the new canvas.
imagecopy($dst_im, $src_im, $x, $y, 0, 0, $image
->getWidth(), $image
->getHeight());
// If the user has said that the source image might contain transparency,
// use the slower, but working algorithm to merge the images.
$minalpha = $transparency ? self::alphaGetMin($src_im) : 0;
// Determines the number of passes for imagecopymergeAlpha().
$steps = $is_vertical ? min($size, $image
->getHeight()) : min($size, $image
->getWidth());
// Creates the reflection on the new canvas.
switch ($position) {
case 'top':
for ($i = 0, $opacity = 50; $i < $steps; ++$i, $opacity = ceil(($steps - $i) / $steps * 100 / 2)) {
self::imagecopymergeAlpha($dst_im, $src_im, 0, $y - $i, 0, $i, $image
->getWidth(), 1, $opacity, $minalpha);
}
break;
case 'bottom':
for ($i = 0, $opacity = 50; $i < $steps; ++$i, $opacity = ceil(($steps - $i) / $steps * 100 / 2)) {
self::imagecopymergeAlpha($dst_im, $src_im, 0, $image
->getHeight() + $i, 0, $image
->getHeight() - $i - 1, $image
->getWidth(), 1, $opacity, $minalpha);
}
break;
case 'left':
for ($i = 0, $opacity = 50; $i < $steps; ++$i, $opacity = ceil(($steps - $i) / $steps * 100 / 2)) {
self::imagecopymergeAlpha($dst_im, $src_im, $x - $i, 0, $i, 0, 1, $image
->getHeight(), $opacity, $minalpha);
}
break;
case 'right':
for ($i = 0, $opacity = 50; $i < $steps; ++$i, $opacity = ceil(($steps - $i) / $steps * 100 / 2)) {
self::imagecopymergeAlpha($dst_im, $src_im, $image
->getWidth() + $i, 0, $image
->getWidth() - $i - 1, 0, 1, $image
->getHeight(), $opacity, $minalpha);
}
break;
}
// Destroy the original image and return the modified image.
imagedestroy($image
->getResource());
$image
->setResource($dst_im)
->setWidth($width)
->setHeight($height);
return TRUE;
}
/**
* A fix to get a function like imagecopymerge with alpha blending.
*
* Main script by aiden dot mail at freemail dot hu.
* Transformed to imagecopymerge_alpha() by rodrigo dot polo at gmail dot com.
*
* @param resource $dst_im
* Destination image link resource.
* @param resource $src_im
* Source image link resource.
* @param int $dst_x
* x-coordinate of destination point.
* @param int $dst_y
* y-coordinate of destination point.
* @param int $src_x
* x-coordinate of source point.
* @param int $src_y
* y-coordinate of source point.
* @param int $src_w
* Source width.
* @param int $src_h
* Source height.
* @param int $pct
* Opacity in percent * 100.
* @param int $minalpha
* Minimum alpha value in the image resource.
*
* @return bool
* Returns TRUE on success or FALSE on failure.
*
* @see http://uk3.php.net/manual/en/function.imagecopymerge.php#88456
*/
protected static function imagecopymergeAlpha(&$dst_im, &$src_im, $dst_x, $dst_y, $src_x, $src_y, $src_w, $src_h, $pct, $minalpha = NULL) {
if (!isset($pct)) {
return FALSE;
}
$pct /= 100;
// Get image width and height.
$w = imagesx($src_im);
$h = imagesy($src_im);
// Turn alpha blending off.
imagealphablending($src_im, FALSE);
if (is_null($minalpha)) {
// Find the most opaque pixel in the image (smallest alpha value).
$minalpha = 127;
for ($x = 0; $x < $w; $x++) {
for ($y = 0; $y < $h; $y++) {
$alpha = imagecolorat($src_im, $x, $y) >> 24 & 0xff;
if ($alpha < $minalpha) {
$minalpha = $alpha;
}
}
}
}
// Loop through image pixels and modify alpha for each.
for ($x = $src_x; $x < $src_x + $src_w; $x++) {
for ($y = $src_y; $y < $src_y + $src_h; $y++) {
// Get current alpha value (represents the transparency).
$colorxy = imagecolorat($src_im, $x, $y);
$alpha = $colorxy >> 24 & 0xff;
// Calculate new alpha.
if ($minalpha !== 127) {
$alpha = 127 + 127 * $pct * ($alpha - 127) / (127 - $minalpha);
}
else {
$alpha += 127 * $pct;
}
// Get the color index with new alpha.
$alphacolorxy = imagecolorallocatealpha($src_im, $colorxy >> 16 & 0xff, $colorxy >> 8 & 0xff, $colorxy & 0xff, $alpha);
// Set pixel with the new color + opacity.
if (!imagesetpixel($src_im, $x, $y, $alphacolorxy)) {
return FALSE;
}
}
}
// The image copy.
imagecopy($dst_im, $src_im, $dst_x, $dst_y, $src_x, $src_y, $src_w, $src_h);
}
/**
* Compute the minimum alpha value of the pixels of a given image resource.
*
* Warning, this function is very expensive.
*
* @param resource $src_im
* Source image link resource.
*
* @return int
* Minimum alpha value in the image resource.
*/
protected static function alphaGetMin($src_im) {
$w = imagesx($src_im);
$h = imagesy($src_im);
// Turn alpha blending off.
imagealphablending($src_im, FALSE);
// Find the most opaque pixel in the image (smallest alpha value).
$minalpha = 127;
for ($x = 0; $x < $w; $x++) {
for ($y = 0; $y < $h; $y++) {
$alpha = imagecolorat($src_im, $x, $y) >> 24 & 0xff;
if ($alpha < $minalpha) {
$minalpha = $alpha;
}
}
}
return $minalpha;
}
}Classes
Name |
Description |
|---|---|
| GDToolkitReflect | Creates a reflect operation for the GD library. |