Version 1

[yaffs-website] / web / core / modules / system / src / Plugin / ImageToolkit / Operation / gd / Rotate.php

diff --git a/web/core/modules/system/src/Plugin/ImageToolkit/Operation/gd/Rotate.php b/web/core/modules/system/src/Plugin/ImageToolkit/Operation/gd/Rotate.php
new file mode 100644 (file)
index 0000000..4335612
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+++ b/web/core/modules/system/src/Plugin/ImageToolkit/Operation/gd/Rotate.php
@@ -0,0 +1,117 @@
+<?php
+
+namespace Drupal\system\Plugin\ImageToolkit\Operation\gd;
+
+use Drupal\Component\Utility\Color;
+
+/**
+ * Defines GD2 rotate operation.
+ *
+ * @ImageToolkitOperation(
+ *   id = "gd_rotate",
+ *   toolkit = "gd",
+ *   operation = "rotate",
+ *   label = @Translation("Rotate"),
+ *   description = @Translation("Rotates an image by the given number of degrees.")
+ * )
+ */
+class Rotate extends GDImageToolkitOperationBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function arguments() {
+    return [
+      'degrees' => [
+        'description' => 'The number of (clockwise) degrees to rotate the image',
+      ],
+      'background' => [
+        'description' => "A string specifying the hexadecimal color code to use as background for the uncovered area of the image after the rotation. E.g. '#000000' for black, '#ff00ff' for magenta, and '#ffffff' for white. For images that support transparency, this will default to transparent white",
+        'required' => FALSE,
+        'default' => NULL,
+      ],
+    ];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function validateArguments(array $arguments) {
+    // PHP 5.5 GD bug: https://bugs.php.net/bug.php?id=65148: To prevent buggy
+    // behavior on negative multiples of 90 degrees we convert any negative
+    // angle to a positive one between 0 and 360 degrees.
+    $arguments['degrees'] -= floor($arguments['degrees'] / 360) * 360;
+
+    // Validate or set background color argument.
+    if (!empty($arguments['background'])) {
+      // Validate the background color: Color::hexToRgb does so for us.
+      $background = Color::hexToRgb($arguments['background']) + [ 'alpha' => 0 ];
+    }
+    else {
+      // Background color is not specified: use transparent white as background.
+      $background = ['red' => 255, 'green' => 255, 'blue' => 255, 'alpha' => 127];
+    }
+    // Store the color index for the background as that is what GD uses.
+    $arguments['background_idx'] = imagecolorallocatealpha($this->getToolkit()->getResource(), $background['red'], $background['green'], $background['blue'], $background['alpha']);
+
+    if ($this->getToolkit()->getType() === IMAGETYPE_GIF) {
+      // GIF does not work with a transparency channel, but can define 1 color
+      // in its palette to act as transparent.
+
+      // Get the current transparent color, if any.
+      $gif_transparent_id = imagecolortransparent($this->getToolkit()->getResource());
+      if ($gif_transparent_id !== -1) {
+        // The gif already has a transparent color set: remember it to set it on
+        // the rotated image as well.
+        $arguments['gif_transparent_color'] = imagecolorsforindex($this->getToolkit()->getResource(), $gif_transparent_id);
+
+        if ($background['alpha'] >= 127) {
+          // We want a transparent background: use the color already set to act
+          // as transparent, as background.
+          $arguments['background_idx'] = $gif_transparent_id;
+        }
+      }
+      else {
+        // The gif does not currently have a transparent color set.
+        if ($background['alpha'] >= 127) {
+          // But as the background is transparent, it should get one.
+          $arguments['gif_transparent_color'] = $background;
+        }
+      }
+    }
+
+    return $arguments;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function execute(array $arguments) {
+    // PHP installations using non-bundled GD do not have imagerotate.
+    if (!function_exists('imagerotate')) {
+      $this->logger->notice('The image %file could not be rotated because the imagerotate() function is not available in this PHP installation.', ['%file' => $this->getToolkit()->getSource()]);
+      return FALSE;
+    }
+
+    // Stores the original GD resource.
+    $original_res = $this->getToolkit()->getResource();
+
+    if ($new_res = imagerotate($this->getToolkit()->getResource(), 360 - $arguments['degrees'], $arguments['background_idx'])) {
+      $this->getToolkit()->setResource($new_res);
+      imagedestroy($original_res);
+
+      // GIFs need to reassign the transparent color after performing the
+      // rotate, but only do so, if the image already had transparency of its
+      // own, or the rotate added a transparent background.
+      if (!empty($arguments['gif_transparent_color'])) {
+        $transparent_idx = imagecolorexactalpha($this->getToolkit()->getResource(), $arguments['gif_transparent_color']['red'], $arguments['gif_transparent_color']['green'], $arguments['gif_transparent_color']['blue'], $arguments['gif_transparent_color']['alpha']);
+        imagecolortransparent($this->getToolkit()->getResource(), $transparent_idx);
+      }
+
+      return TRUE;
+    }
+
+    return FALSE;
+  }
+
+}