' . t('Use this form to upload an image and choose an Image Style to use when displaying the image. This demonstrates basic use of the Drupal 7 Image styles & effects system.') . '
'; $output .= '' . t('Image styles can be added/edited using the !link.', array('!link' => l(t('Image styles UI'), 'admin/config/media/image-styles'))) . '
'; return $output; } } /** * Implements hook_image_default_styles(). * * hook_image_default_styles() declares to Drupal any image styles that are * provided by the module. An image style is a collection of image effects that * are performed in a specified order, manipulating the image and generating a * new derivative image. * * This hook can be used to declare image styles that your module depends on or * allow you to define image styles in code and gain the benefits of using * a version control system. */ function image_example_image_default_styles() { // This hook returns an array, each component of which describes an image // style. The array keys are the machine-readable image style names and // to avoid namespace conflicts should begin with the name of the // implementing module. e.g.) 'mymodule_stylename'. Styles names should // use only alpha-numeric characters, underscores (_), and hyphens (-). $styles = array(); $styles['image_example_style'] = array(); // Each style array consists of an 'effects' array that is made up of // sub-arrays which define the individual image effects that are combined // together to create the image style. $styles['image_example_style']['effects'] = array( array( // Name of the image effect. See image_image_effect_info() in // modules/image/image.effects.inc for a list of image effects available // in Drupal 7 core. 'name' => 'image_scale', // Arguments to pass to the effect callback function. // The arguments that an effect accepts are documented with each // individual image_EFFECT_NAME_effect function. See image_scale_effect() // for an example. 'data' => array( 'width' => 100, 'height' => 100, 'upscale' => 1, ), // The order in which image effects should be applied when using this // style. 'weight' => 0, ), // Add a second effect to this image style. Effects are executed in order // and are cumulative. When applying an image style to an image the result // will be the combination of all effects associated with that style. array( 'name' => 'image_example_colorize', 'data' => array( 'color' => '#FFFF66', ), 'weight' => 1, ), ); return $styles; } /** * Implements hook_image_style_save(). * * Allows modules to respond to updates to an image style's * settings. */ function image_example_image_style_save($style) { // The $style parameter is an image style array with one notable exception. // When a user has chosen to replace a deleted style with another style the // $style['name'] property contains the name of the replacement style and // $style['old_name'] contains the name of the style being deleted. // // Here we update a variable that contains the name of the image style that // the block provided by this module uses when formatting images to use the // new user chosen style name. if (isset($style['old_name']) && $style['old_name'] == variable_get('image_example_style_name', '')) { variable_set('image_example_style_name', $style['name']); } } /** * Implements hook_image_style_delete(). * * This hook allows modules to respond to image styles being deleted. * * @see image_example_style_save() */ function image_example_image_style_delete($style) { // See information about $style paramater in documentation for // image_example_style_save(). // // Update the modules variable that contains the name of the image style // being deleted to the name of the replacement style. if (isset($style['old_name']) && $style['old_name'] == variable_get('image_example_style_name', '')) { variable_set('image_example_style_name', $style['name']); } } /** * Implements hook_image_style_flush(). * * This hook allows modules to respond when a style is being flushed. Styles * are flushed any time a style is updated, an effect associated with the style * is updated, a new effect is added to the style, or an existing effect is * removed. * * Flushing removes all images generated using this style from the host. Once a * style has been flushed derivative images will need to be regenerated. New * images will be generated automatically as needed but it is worth noting that * on a busy site with lots of images this could have an impact on performance. * * Note: This function does not currently have any effect as the example module * does not use any caches. It is demonstrated here for completeness sake only. */ function image_example_style_flush($style) { // Empty any caches populated by our module that could contain stale data // after the style has been flushed. Stale data occurs because the module may // have cached content with a reference to the derivative image which is // being deleted. cache_clear_all('*', 'image_example', TRUE); } /** * Implements hook_image_styles_alter(). * * Allows your module to modify, add, or remove image styles provided * by other modules. The best use of this hook is to modify default styles that * have not been overriden by the user. Altering styles that have been * overriden by the user could have an adverse affect on the user experience. * If you add an effect to a style through this hook and the user attempts to * remove the effect it will immediatly be re-applied. */ function image_example_image_styles_alter(&$styles) { // The $styles paramater is an array of image style arrays keyed by style // name. You can check to see if a style has been overriden by checking the // $styles['stylename']['storage'] property. // Verify that the effect has not been overriden. if ($styles['thumbnail']['storage'] == IMAGE_STORAGE_DEFAULT) { // Add an additional colorize effect to the system provided thumbnail // effect. $styles['thumbnail']['effects'][] = array( 'label' => t('Colorize #FFFF66'), 'name' => 'image_example_colorize', 'effect callback' => 'image_example_colorize_effect', 'data' => array( 'color' => '#FFFF66', ), 'weight' => 1, ); } } /** * Implements hook_image_effect_info(). * * This hook allows your module to define additional image manipulation effects * that can be used with image styles. */ function image_example_image_effect_info() { $effects = array(); // The array is keyed on the machine-readable effect name. $effects['image_example_colorize'] = array( // Human readable name of the effect. 'label' => t('Colorize'), // (optional) Brief description of the effect that will be shown when // adding or configuring this image effect. 'help' => t('The colorize effect will first remove all color from the source image and then tint the image using the color specified.'), // Name of function called to perform this effect. 'effect callback' => 'image_example_colorize_effect', // (optional) Name of function that provides a $form array with options for // configuring the effect. Note that you only need to return the fields // specific to your module. Submit buttons will be added automatically, and // configuration options will be serailized and added to the 'data' element // of the effect. The function will recieve the $effect['data'] array as // its only parameter. 'form callback' => 'image_example_colorize_form', // (optional) Name of a theme function that will output a summary of this // effects configuation. Used when displaying list of effects associated // with an image style. In this example the function // theme_image_example_colorize_summary will be called via the theme() // function. Your module must also implement hook_theme() in order for this // function to work correctly. See image_example_theme() and // theme_image_example_colorize_summary(). 'summary theme' => 'image_example_colorize_summary', ); return $effects; } /** * Form Builder; Configuration settings for colorize effect. * * Create a $form array with the fields necessary for configuring the * image_example_colorize effect. * * Note that this is not a complete form, it only contains the portion of the * form for configuring the colorize options. Therefore it does not not need to * include metadata about the effect, nor a submit button. * * @param array $data * The current configuration for this colorize effect. */ function image_example_colorize_form($data) { $form = array(); // You do not need to worry about handling saving/updating/deleting of the // data collected. The image module will automatically serialize and store // all data associated with an effect. $form['color'] = array( '#type' => 'textfield', '#title' => t('Color'), '#description' => t('The color to use when colorizing the image. Use web-style hex colors. e.g.) #FF6633.'), '#default_value' => isset($data['color']) ? $data['color'] : '', '#size' => 7, '#max_length' => 7, '#required' => TRUE, ); return $form; } /** * Image effect callback; Colorize an image resource. * * @param object $image * An image object returned by image_load(). * @param array $data * An array of attributes to use when performing the colorize effect with the * following items: * - "color": The web-style hex color to use when colorizing the image. * * @return bool * TRUE on success. FALSE on failure to colorize image. */ function image_example_colorize_effect(&$image, $data) { // Image manipulation should be done to the $image->resource, which will be // automatically saved as a new image once all effects have been applied. // If your effect makes changes to the $image->resource that relate to any // information stored in the $image->info array (width, height, etc.) you // should update that information as well. See modules/system/image.gd.inc // for examples of functions that perform image manipulations. // // Not all GD installations are created equal. It is a good idea to check for // the existence of image manipulation functions before using them. // PHP installations using non-bundled GD do not have imagefilter(). More // information about image manipulation functions is available in the PHP // manual. http://www.php.net/manual/en/book.image.php if (!function_exists('imagefilter')) { watchdog('image', 'The image %image could not be colorized because the imagefilter() function is not available in this PHP installation.', array('%file' => $image->source)); return FALSE; } // Verify that Drupal is using the PHP GD library for image manipulations // since this effect depends on functions in the GD library. if ($image->toolkit != 'gd') { watchdog('image', 'Image colorize failed on %path. Using non GD toolkit.', array('%path' => $image->source), WATCHDOG_ERROR); return FALSE; } // Convert short #FFF syntax to full #FFFFFF syntax. if (strlen($data['color']) == 4) { $c = $data['color']; $data['color'] = $c[0] . $c[1] . $c[1] . $c[2] . $c[2] . $c[3] . $c[3]; } // Convert #FFFFFF syntax to hexadecimal colors. $data['color'] = hexdec(str_replace('#', '0x', $data['color'])); // Convert the hexadecimal color value to a color index value. $rgb = array(); for ($i = 16; $i >= 0; $i -= 8) { $rgb[] = (($data['color'] >> $i) & 0xFF); } // First desaturate the image, and then apply the new color. imagefilter($image->resource, IMG_FILTER_GRAYSCALE); imagefilter($image->resource, IMG_FILTER_COLORIZE, $rgb[0], $rgb[1], $rgb[2]); return TRUE; } /** * Implements hook_theme(). */ function image_example_theme() { return array( 'image_example_colorize_summary' => array( 'variables' => array('data' => NULL), ), 'image_example_image' => array( 'variables' => array('image' => NULL, 'style' => NULL), 'file' => 'image_example.pages.inc', ), ); } /** * Formats a summary of an image colorize effect. * * @param array $variables * An associative array containing: * - data: The current configuration for this colorize effect. */ function theme_image_example_colorize_summary($variables) { $data = $variables['data']; return t('as color #@color.', array('@color' => $data['color'])); } /** * @} End of "defgroup image_example". */