diff includes/image.gd.inc @ 1:c1f4ac30525a 6.0

Drupal 6.0
author Franck Deroche <webmaster@defr.org>
date Tue, 23 Dec 2008 14:28:28 +0100
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/includes/image.gd.inc	Tue Dec 23 14:28:28 2008 +0100
@@ -0,0 +1,221 @@
+<?php
+// $Id: image.gd.inc,v 1.4 2008/01/15 10:17:42 goba Exp $
+
+/**
+ * @file
+ * GD2 toolkit for image manipulation within Drupal.
+ */
+
+/**
+ * @ingroup image
+ * @{
+ */
+
+/**
+ * Retrieve information about the toolkit.
+ */
+function image_gd_info() {
+  return array('name' => 'gd', 'title' => t('GD2 image manipulation toolkit'));
+}
+
+/**
+ * Retrieve settings for the GD2 toolkit.
+ */
+function image_gd_settings() {
+  if (image_gd_check_settings()) {
+    $form = array();
+    $form['status'] = array(
+      '#value' => t('The GD toolkit is installed and working properly.')
+    );
+
+    $form['image_jpeg_quality'] = array(
+      '#type' => 'textfield',
+      '#title' => t('JPEG quality'),
+      '#description' => t('Define the image quality for JPEG manipulations. Ranges from 0 to 100. Higher values mean better image quality but bigger files.'),
+      '#size' => 10,
+      '#maxlength' => 3,
+      '#default_value' => variable_get('image_jpeg_quality', 75),
+      '#field_suffix' => t('%'),
+    );
+    $form['#element_validate'] = array('image_gd_settings_validate');
+    
+    return $form;
+  }
+  else {
+    form_set_error('image_toolkit', t('The GD image toolkit requires that the GD module for PHP be installed and configured properly. For more information see <a href="@url">PHP\'s image documentation</a>.', array('@url' => 'http://php.net/image')));
+    return FALSE;
+  }
+}
+
+/**
+ * Validate the submitted GD settings.
+ */
+function image_gd_settings_validate($form, &$form_state) {
+  // Validate image quality range.
+  $value = $form_state['values']['image_jpeg_quality'];
+  if (!is_numeric($value) || $value < 0 || $value > 100) {
+    form_set_error('image_jpeg_quality', t('JPEG quality must be a number between 0 and 100.'));
+  }
+}
+
+/**
+ * Verify GD2 settings (that the right version is actually installed).
+ *
+ * @return
+ *   A boolean indicating if the GD toolkit is avaiable on this machine.
+ */
+function image_gd_check_settings() {
+  if ($check = get_extension_funcs('gd')) {
+    if (in_array('imagegd2', $check)) {
+      // GD2 support is available.
+      return TRUE;
+    }
+  }
+  return FALSE;
+}
+
+/**
+ * Scale an image to the specified size using GD.
+ */
+function image_gd_resize($source, $destination, $width, $height) {
+  if (!file_exists($source)) {
+    return FALSE;
+  }
+
+  $info = image_get_info($source);
+  if (!$info) {
+    return FALSE;
+  }
+
+  $im = image_gd_open($source, $info['extension']);
+  if (!$im) {
+    return FALSE;
+  }
+
+  $res = imagecreatetruecolor($width, $height);
+  if ($info['extension'] == 'png') {
+    $transparency = imagecolorallocatealpha($res, 0, 0, 0, 127);
+    imagealphablending($res, FALSE);
+    imagefilledrectangle($res, 0, 0, $width, $height, $transparency);
+    imagealphablending($res, TRUE);
+    imagesavealpha($res, TRUE);
+  }
+  elseif ($info['extension'] == 'gif') {
+    // If we have a specific transparent color.
+    $transparency_index = imagecolortransparent($im);
+    if ($transparency_index >= 0) {
+      // Get the original image's transparent color's RGB values.
+      $transparent_color = imagecolorsforindex($im, $transparency_index);
+      // Allocate the same color in the new image resource.
+      $transparency_index = imagecolorallocate($res, $transparent_color['red'], $transparent_color['green'], $transparent_color['blue']);
+      // Completely fill the background of the new image with allocated color.
+      imagefill($res, 0, 0, $transparency_index);
+      // Set the background color for new image to transparent.
+      imagecolortransparent($res, $transparency_index);
+      // Find number of colors in the images palette.
+      $number_colors = imagecolorstotal($im);
+      // Convert from true color to palette to fix transparency issues.
+      imagetruecolortopalette($res, TRUE, $number_colors);
+    }
+  }
+  imagecopyresampled($res, $im, 0, 0, 0, 0, $width, $height, $info['width'], $info['height']);
+  $result = image_gd_close($res, $destination, $info['extension']);
+
+  imagedestroy($res);
+  imagedestroy($im);
+
+  return $result;
+}
+
+/**
+ * Rotate an image the given number of degrees.
+ */
+function image_gd_rotate($source, $destination, $degrees, $background = 0x000000) {
+  if (!function_exists('imageRotate')) {
+    return FALSE;
+  }
+
+  $info = image_get_info($source);
+  if (!$info) {
+    return FALSE;
+  }
+
+  $im = image_gd_open($source, $info['extension']);
+  if (!$im) {
+    return FALSE;
+  }
+
+  $res = imageRotate($im, $degrees, $background);
+  $result = image_gd_close($res, $destination, $info['extension']);
+
+  return $result;
+}
+
+/**
+ * Crop an image using the GD toolkit.
+ */
+function image_gd_crop($source, $destination, $x, $y, $width, $height) {
+  $info = image_get_info($source);
+  if (!$info) {
+    return FALSE;
+  }
+
+  $im = image_gd_open($source, $info['extension']);
+  $res = imageCreateTrueColor($width, $height);
+  imageCopy($res, $im, 0, 0, $x, $y, $width, $height);
+  $result = image_gd_close($res, $destination, $info['extension']);
+
+  imageDestroy($res);
+  imageDestroy($im);
+
+  return $result;
+}
+
+/**
+ * GD helper function to create an image resource from a file.
+ *
+ * @param $file
+ *   A string file path where the iamge should be saved.
+ * @param $extension
+ *   A string containing one of the following extensions: gif, jpg, jpeg, png.
+ * @return
+ *   An image resource, or FALSE on error.
+ */
+function image_gd_open($file, $extension) {
+  $extension = str_replace('jpg', 'jpeg', $extension);
+  $open_func = 'imageCreateFrom'. $extension;
+  if (!function_exists($open_func)) {
+    return FALSE;
+  }
+  return $open_func($file);
+}
+
+/**
+ * GD helper to write an image resource to a destination file.
+ *
+ * @param $res
+ *   An image resource created with image_gd_open().
+ * @param $destination
+ *   A string file path where the iamge should be saved.
+ * @param $extension
+ *   A string containing one of the following extensions: gif, jpg, jpeg, png.
+ * @return
+ *   Boolean indicating success.
+ */
+function image_gd_close($res, $destination, $extension) {
+  $extension = str_replace('jpg', 'jpeg', $extension);
+  $close_func = 'image'. $extension;
+  if (!function_exists($close_func)) {
+    return FALSE;
+  }
+  if ($extension == 'jpeg') {
+    return $close_func($res, $destination, variable_get('image_jpeg_quality', 75));
+  }
+  else {
+    return $close_func($res, $destination);
+  }
+}
+
+/**
+ * @} End of "ingroup image".
+ */