color.module 25.8 KB
Newer Older
1
<?php
2 3 4 5
/**
 * @file
 * Allows users to change the color scheme of themes.
 */
6

7
use Drupal\Core\Asset\CssOptimizer;
8
use Drupal\Component\Utility\String;
9

10
/**
11
 * Implements hook_help().
12 13 14 15
 */
function color_help($path, $arg) {
  switch ($path) {
    case 'admin/help#color':
16
      $output = '<h3>' . t('About') . '</h3>';
17
      $output .= '<p>' . t('The Color module allows users with the <em>Administer site configuration</em> permission to change the color scheme (color of links, backgrounds, text, and other theme elements) of themes that are compatible with it. For more information, see <a href="!color_do">the online documentation for the Color module</a>.', array('!color_do' => 'https://drupal.org/documentation/modules/color')) . '</p>';
18 19
      $output .= '<h3>' . t('Uses') . '</h3>';
      $output .= '<dl>';
20
      $output .= '<dt>' . t('Changing colors') . '</dt>';
21 22
      $output .= '<dd><p>' . t('To change the color settings, select the <em>Settings</em> link for your theme on the <a href="!appearance">Appearance</a> page. If the color picker does not appear than the theme is not compatible with the Color module.', array('!appearance' => \Drupal::url('system.themes_page'))) . '</p>';
      $output .= '<p>' . t('The Color module saves a modified copy of the theme\'s specified stylesheets in the files directory. This means that if you make any manual changes to your theme\'s stylesheet, <em>you must save your color settings again, even if they haven\'t changed</em>. This step is required because the module stylesheets (in the files directory) need to be recreated to include your changes.') . '</p></dd>';
23
      $output .= '</dl>';
24 25 26 27
      return $output;
  }
}

28
/**
29
 * Implements hook_theme().
30 31 32 33
 */
function color_theme() {
  return array(
    'color_scheme_form' => array(
34
      'render element' => 'form',
35
      'template' => 'color-scheme-form',
36 37 38
    ),
  );
}
39

40
/**
41
 * Implements hook_form_FORM_ID_alter().
42
 */
43
function color_form_system_theme_settings_alter(&$form, &$form_state) {
44
  if (isset($form_state['build_info']['args'][0]) && ($theme = $form_state['build_info']['args'][0]) && color_get_info($theme) && function_exists('gd_info')) {
45
    $form['color'] = array(
46
      '#type' => 'details',
47
      '#title' => t('Color scheme'),
48
      '#open' => TRUE,
49 50 51 52
      '#weight' => -1,
      '#attributes' => array('id' => 'color_scheme_form'),
      '#theme' => 'color_scheme_form',
    );
53
    $form['color'] += color_scheme_form($form, $form_state, $theme);
54
    $form['#validate'][] = 'color_scheme_form_validate';
55
    $form['#submit'][] = 'color_scheme_form_submit';
56
  }
57 58
}

59
/**
60
 * Implements hook_css_alter().
61
 *
62
 * Replaces style sheets with color-altered style sheets.
63
 */
64
function color_css_alter(&$css) {
65
  global $theme_key;
66
  $themes = list_themes();
67 68

  // Override stylesheets.
69
  $color_paths = \Drupal::config('color.' . $theme_key)->get('stylesheets');
70 71

  if (!empty($color_paths) && !empty($themes[$theme_key]->stylesheets['all'])) {
72

73
    foreach ($themes[$theme_key]->stylesheets['all'] as $old_path) {
74 75 76 77 78
      // Loop over the path array with recolored CSS files to find matching
      // paths which could replace the non-recolored paths.
      foreach ($color_paths as $color_path) {
        // Color module currently requires unique file names to be used,
        // which allows us to compare different file paths.
79
        if (drupal_basename($old_path) == drupal_basename($color_path)) {
80 81
          // Replace the path to the new css file.
          // This keeps the order of the stylesheets intact.
82
          $css[drupal_basename($old_path)]['data'] = $color_path;
83 84 85
        }
      }
    }
86
  }
87 88 89
}

/**
90
 * Implements hook_preprocess_page().
91
 *
92
 * Replace the logo with the colored version if available.
93
 */
94
function color_preprocess_page(&$variables) {
95
  global $theme_key;
96

97
  // Override logo.
98
  $logo = \Drupal::config('color.' . $theme_key)->get('logo');
99 100
  if ($logo && $variables['logo'] && preg_match('!' . $theme_key . '/logo.png$!', $variables['logo'])) {
    $variables['logo'] = file_create_url($logo);
101 102 103 104
  }
}

/**
105
 * Retrieves the Color module information for a particular theme.
106 107
 */
function color_get_info($theme) {
108 109 110 111 112 113
  static $theme_info = array();

  if (isset($theme_info[$theme])) {
    return $theme_info[$theme];
  }

114
  $path = drupal_get_path('theme', $theme);
115
  $file = DRUPAL_ROOT . '/' . $path . '/color/color.inc';
116 117
  if ($path && file_exists($file)) {
    include $file;
118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133
    // Add in default values.
    $info += array(
      // CSS files (excluding @import) to rewrite with new color scheme.
      'css' => array(),
      // Files to copy.
      'copy' => array(),
      // Gradient definitions.
      'gradients' => array(),
      // Color areas to fill (x, y, width, height).
      'fill' => array(),
      // Coordinates of all the theme slices (x, y, width, height) with their
      // filename as used in the stylesheet.
      'slices' => array(),
      // Reference color used for blending.
      'blend_target' => '#ffffff',
    );
134
    $theme_info[$theme] = $info;
135 136 137 138 139
    return $info;
  }
}

/**
140
 * Retrieves the color palette for a particular theme.
141
 */
142
function color_get_palette($theme, $default = FALSE) {
143
  // Fetch and expand default palette.
144
  $info = color_get_info($theme);
145
  $palette = $info['schemes']['default']['colors'];
146

147 148 149 150
  if ($default) {
    return $palette;
  }

151
  // Load variable.
152
  // @todo Default color config should be moved to yaml in the theme.
153
  return \Drupal::config('color.' . $theme)->get('palette') ?: $palette;
154 155 156
}

/**
157 158 159 160 161 162 163 164
 * Form constructor for the color configuration form for a particular theme.
 *
 * @param $theme
 *   The machine name of the theme whose color settings are being configured.
 *
 * @see color_scheme_form_validate()
 * @see color_scheme_form_submit()
 * @ingroup forms
165
 */
166
function color_scheme_form($complete_form, &$form_state, $theme) {
167 168 169
  $base = drupal_get_path('module', 'color');
  $info = color_get_info($theme);

170 171 172 173 174 175 176 177 178
  $info['schemes'][''] = array('title' => t('Custom'), 'colors' => array());
  $color_sets = array();
  $schemes = array();
  foreach ($info['schemes'] as $key => $scheme) {
    $color_sets[$key] = $scheme['title'];
    $schemes[$key] = $scheme['colors'];
    $schemes[$key] += $info['schemes']['default']['colors'];
  }

179
  // See if we're using a predefined scheme.
180
  // Note: we use the original theme when the default scheme is chosen.
181
  $current_scheme = \Drupal::config('color.' . $theme)->get('palette');
182 183 184 185 186 187 188 189 190 191 192 193 194 195
  foreach ($schemes as $key => $scheme) {
    if ($current_scheme == $scheme) {
      $scheme_name = $key;
      break;
    }
  }
  if (empty($scheme_name)) {
    if (empty($current_scheme)) {
      $scheme_name = 'default';
    }
    else {
      $scheme_name = '';
    }
  }
196

197
  // Add scheme selector.
198 199 200
  $form['scheme'] = array(
    '#type' => 'select',
    '#title' => t('Color set'),
201 202
    '#options' => $color_sets,
    '#default_value' => $scheme_name,
203 204
    '#attached' => array(
      'library' => array(
205
        array('color', 'drupal.color'),
206 207 208
      ),
      // Add custom CSS.
      'css' => array(
209
        $base . '/css/color.admin.css' => array(),
210 211 212 213 214
      ),
      // Add custom JavaScript.
      'js' => array(
        array(
          'data' => array(
215 216 217 218 219
            'color' => array(
              'reference' => color_get_palette($theme, TRUE),
              'schemes' => $schemes,
            ),
            'gradients' => $info['gradients'],
220 221 222
          ),
          'type' => 'setting',
        ),
223 224
      ),
    ),
225 226
  );

227
  // Add palette fields.
228
  $palette = color_get_palette($theme);
229
  $names = $info['fields'];
230
  $form['palette']['#tree'] = TRUE;
231
  foreach ($palette as $name => $value) {
232 233 234
    if (isset($names[$name])) {
      $form['palette'][$name] = array(
        '#type' => 'textfield',
235
        '#title' => String::checkPlain($names[$name]),
236
        '#value_callback' => 'color_palette_color_value',
237 238
        '#default_value' => $value,
        '#size' => 8,
239
        '#attributes' => array('dir' => 'ltr'),
240 241
      );
    }
242
  }
243
  $form['theme'] = array('#type' => 'value', '#value' => $theme);
244 245 246 247 248 249
  $form['info'] = array('#type' => 'value', '#value' => $info);

  return $form;
}

/**
250
 * Prepares variables for color scheme form templates.
251
 *
252 253 254
 * Default template: color-scheme-form.html.twig.
 *
 * @param array $variables
255 256
 *   An associative array containing:
 *   - form: A render element representing the form.
257
 */
258
function template_preprocess_color_scheme_form(&$variables) {
259
  $form = &$variables['form'];
260

261 262
  $theme = $form['theme']['#value'];
  $info = $form['info']['#value'];
263
  $path = drupal_get_path('theme', $theme) . '/';
264

265 266 267 268
  if (isset($info['preview_css'])) {
    $preview_css_path = $path . $info['preview_css'];
    $form['scheme']['#attached']['css'][$preview_css_path] = array();
  }
269 270
  $preview_js_path = isset($info['preview_js']) ? $path . $info['preview_js'] : drupal_get_path('module', 'color') . '/' . 'preview.js';
  // Add the JS at a weight below color.js.
271
  $form['scheme']['#attached']['js'][$preview_js_path] = array('weight' => -1);
272

273 274
  // Attempt to load preview HTML if the theme provides it.
  $preview_html_path = DRUPAL_ROOT . '/' . (isset($info['preview_html']) ? drupal_get_path('theme', $theme) . '/' . $info['preview_html'] : drupal_get_path('module', 'color') . '/preview.html');
275
  $variables['html_preview'] = file_get_contents($preview_html_path);
276 277
}

278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323
/**
 * Determines the value for a palette color field.
 *
 * @param array $element
 *   The form element whose value is being populated.
 * @param string|bool $input
 *   The incoming input to populate the form element. If this is FALSE,
 *   the element's default value should be returned.
 * @param array $form_state
 *   A keyed array containing the current state of the form.
 *
 * @return string
 *   The data that will appear in the $form_state['values'] collection for this
 *   element. Return nothing to use the default.
 */
function color_palette_color_value($element, $input = FALSE, $form_state = array()) {
  // If we suspect a possible cross-site request forgery attack, only accept
  // hexadecimal CSS color strings from user input, to avoid problems when this
  // value is used in the JavaScript preview.
  if ($input !== FALSE) {
    // Start with the provided value for this textfield, and validate that if
    // necessary, falling back on the default value.
    $value = form_type_textfield_value($element, $input, $form_state);
    if (!$value || !isset($form_state['complete form']['#token']) || color_valid_hexadecimal_string($value) || drupal_valid_token($form_state['values']['form_token'], $form_state['complete form']['#token'])) {
      return $value;
    }
    else {
      return $element['#default_value'];
    }
  }
}

/**
 * Determines if a hexadecimal CSS color string is valid.
 *
 * @param string $color
 *   The string to check.
 *
 * @return bool
 *   TRUE if the string is a valid hexadecimal CSS color string, or FALSE if it
 *   isn't.
 */
function color_valid_hexadecimal_string($color) {
  return preg_match('/^#([a-f0-9]{3}){1,2}$/iD', $color);
}

324
/**
325 326 327
 * Form validation handler for color_scheme_form().
 *
 * @see color_scheme_form_submit()
328 329 330 331
 */
function color_scheme_form_validate($form, &$form_state) {
  // Only accept hexadecimal CSS color strings to avoid XSS upon use.
  foreach ($form_state['values']['palette'] as $key => $color) {
332
    if (!color_valid_hexadecimal_string($color)) {
333
      form_set_error('palette][' . $key, $form_state, t('You must enter a valid hexadecimal color value for %name.', array('%name' => $form['color']['palette'][$key]['#title'])));
334 335 336 337
    }
  }
}

338
/**
339 340 341
 * Form submission handler for color_scheme_form().
 *
 * @see color_scheme_form_validate()
342
 */
343
function color_scheme_form_submit($form, &$form_state) {
344

345
  // Get theme coloring info.
346
  if (!isset($form_state['values']['info'])) {
347 348
    return;
  }
349 350
  $theme = $form_state['values']['theme'];
  $info = $form_state['values']['info'];
351

352
  $config = \Drupal::config('color.' . $theme);
353

354
  // Resolve palette.
355 356
  $palette = $form_state['values']['palette'];
  if ($form_state['values']['scheme'] != '') {
357 358 359 360
    foreach ($palette as $key => $color) {
      if (isset($info['schemes'][$form_state['values']['scheme']]['colors'][$key])) {
        $palette[$key] = $info['schemes'][$form_state['values']['scheme']]['colors'][$key];
      }
361
    }
362
    $palette += $info['schemes']['default']['colors'];
363 364
  }

365
  // Make sure enough memory is available.
366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384
  if (isset($info['base_image'])) {
    // Fetch source image dimensions.
    $source = drupal_get_path('theme', $theme) . '/' . $info['base_image'];
    list($width, $height) = getimagesize($source);

    // We need at least a copy of the source and a target buffer of the same
    // size (both at 32bpp).
    $required = $width * $height * 8;
    // We intend to prevent color scheme changes if there isn't enough memory
    // available.  memory_get_usage(TRUE) returns a more accurate number than
    // memory_get_usage(), therefore we won't inadvertently reject a color
    // scheme change based on a faulty memory calculation.
    $usage = memory_get_usage(TRUE);
    $memory_limit = ini_get('memory_limit');
    $size = parse_size($memory_limit);
    if (!drupal_check_memory_limit($usage + $required, $memory_limit)) {
      drupal_set_message(t('There is not enough memory available to PHP to change this theme\'s color scheme. You need at least %size more. Check the <a href="@url">PHP documentation</a> for more information.', array('%size' => format_size($usage + $required - $size), '@url' => 'http://www.php.net/manual/ini.core.php#ini.sect.resource-limits')), 'error');
      return;
    }
385 386
  }

387
  // Delete old files.
388 389 390 391 392
  $files = $config->get('files');
  if (isset($files)) {
    foreach ($files as $file) {
      @drupal_unlink($file);
    }
393
  }
394
  if (isset($file) && $file = dirname($file)) {
395
    @drupal_rmdir($file);
396 397
  }

398
  // No change in color config, use the standard theme from color.inc.
399
  if (implode(',', color_get_palette($theme, TRUE)) == implode(',', $palette)) {
400
    $config->delete();
401 402 403
    return;
  }

404
  // Prepare target locations for generated files.
405
  $id = $theme . '-' . substr(hash('sha256', serialize($palette) . microtime()), 0, 8);
406
  $paths['color'] = file_default_scheme() . '://color';
407
  $paths['target'] = $paths['color'] . '/' . $id;
408
  foreach ($paths as $path) {
409
    file_prepare_directory($path, FILE_CREATE_DIRECTORY);
410
  }
411
  $paths['target'] = $paths['target'] . '/';
412
  $paths['id'] = $id;
413
  $paths['source'] = drupal_get_path('theme', $theme) . '/';
414 415
  $paths['files'] = $paths['map'] = array();

416
  // Save palette and logo location.
417 418 419 420
  $config
    ->set('palette', $palette)
    ->set('logo', $paths['target'] . 'logo.png')
    ->save();
421

422
  // Copy over neutral images.
423
  foreach ($info['copy'] as $file) {
424
    $base = drupal_basename($file);
425
    $source = $paths['source'] . $file;
426
    $filepath = file_unmanaged_copy($source, $paths['target'] . $base);
427
    $paths['map'][$file] = $base;
428
    $paths['files'][] = $filepath;
429 430
  }

431
  // Render new images, if image has been provided.
432
  if (isset($info['base_image'])) {
433 434
    _color_render_images($theme, $info, $paths, $palette);
  }
435

436 437 438
  // Rewrite theme stylesheets.
  $css = array();
  foreach ($info['css'] as $stylesheet) {
439
    // Build a temporary array with CSS files.
440 441 442 443 444 445
    $files = array();
    if (file_exists($paths['source'] . $stylesheet)) {
      $files[] = $stylesheet;
    }

    foreach ($files as $file) {
446
      $css_optimizer = new CssOptimizer();
447 448
      // Aggregate @imports recursively for each configured top level CSS file
      // without optimization. Aggregation and optimization will be
449
      // handled by drupal_build_css_cache() only.
450
      $style = $css_optimizer->loadFile($paths['source'] . $file, FALSE);
451 452 453

      // Return the path to where this CSS file originated from, stripping
      // off the name of the file at the end of the path.
454
      $css_optimizer->rewriteFileURIBasePath = base_path() . dirname($paths['source'] . $file) . '/';
455 456

      // Prefix all paths within this CSS file, ignoring absolute paths.
457
      $style = preg_replace_callback('/url\([\'"]?(?![a-z]+:|\/+)([^\'")]+)[\'"]?\)/i', array($css_optimizer, 'rewriteFileURI'), $style);
458 459 460

      // Rewrite stylesheet with new colors.
      $style = _color_rewrite_stylesheet($theme, $info, $paths, $palette, $style);
461
      $base_file = drupal_basename($file);
462 463
      $css[] = $paths['target'] . $base_file;
      _color_save_stylesheet($paths['target'] . $base_file, $style, $paths);
464
    }
465
  }
466

467
  // Maintain list of files.
468 469 470 471
  $config
    ->set('stylesheets', $css)
    ->set('files', $paths['files'])
    ->save();
472 473 474
}

/**
475
 * Rewrites the stylesheet to match the colors in the palette.
476
 */
477
function _color_rewrite_stylesheet($theme, &$info, &$paths, $palette, $style) {
478
  // Prepare color conversion table.
479 480 481 482
  $conversion = $palette;
  foreach ($conversion as $k => $v) {
    $conversion[$k] = drupal_strtolower($v);
  }
483
  $default = color_get_palette($theme, TRUE);
484 485

  // Split off the "Don't touch" section of the stylesheet.
486
  $split = "Color Module: Don't touch";
487
  if (strpos($style, $split) !== FALSE) {
488 489
    list($style, $fixed) = explode($split, $style);
  }
490 491 492

  // Find all colors in the stylesheet and the chunks in between.
  $style = preg_split('/(#[0-9a-f]{6}|#[0-9a-f]{3})/i', $style, -1, PREG_SPLIT_DELIM_CAPTURE);
493
  $is_color = FALSE;
494 495 496
  $output = '';
  $base = 'base';

497
  // Iterate over all the parts.
498 499 500
  foreach ($style as $chunk) {
    if ($is_color) {
      $chunk = drupal_strtolower($chunk);
501
      // Check if this is one of the colors in the default palette.
502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517
      if ($key = array_search($chunk, $default)) {
        $chunk = $conversion[$key];
      }
      // Not a pre-set color. Extrapolate from the base.
      else {
        $chunk = _color_shift($palette[$base], $default[$base], $chunk, $info['blend_target']);
      }
    }
    else {
      // Determine the most suitable base color for the next color.

      // 'a' declarations. Use link.
      if (preg_match('@[^a-z0-9_-](a)[^a-z0-9_-][^/{]*{[^{]+$@i', $chunk)) {
        $base = 'link';
      }
      // 'color:' styles. Use text.
518
      elseif (preg_match('/(?<!-)color[^{:]*:[^{#]*$/i', $chunk)) {
519 520 521 522 523 524 525 526 527 528
        $base = 'text';
      }
      // Reset back to base.
      else {
        $base = 'base';
      }
    }
    $output .= $chunk;
    $is_color = !$is_color;
  }
529 530 531 532
  // Append fixed colors segment.
  if (isset($fixed)) {
    $output .= $fixed;
  }
533

534
  // Replace paths to images.
535
  foreach ($paths['map'] as $before => $after) {
536 537
    $before = base_path() . $paths['source'] . $before;
    $before = preg_replace('`(^|/)(?!../)([^/]+)/../`', '$1', $before);
538 539 540
    $output = str_replace($before, $after, $output);
  }

541
  return $output;
542 543 544
}

/**
545
 * Saves the rewritten stylesheet to disk.
546
 */
547
function _color_save_stylesheet($file, $style, &$paths) {
548
  $filepath = file_unmanaged_save_data($style, $file, FILE_EXISTS_REPLACE);
549
  $paths['files'][] = $filepath;
550 551

  // Set standard file permissions for webserver-generated files.
552
  drupal_chmod($file);
553 554 555
}

/**
556
 * Renders images that match a given palette.
557 558
 */
function _color_render_images($theme, &$info, &$paths, $palette) {
Steven Wittens's avatar
Steven Wittens committed
559
  // Prepare template image.
560
  $source = $paths['source'] . '/' . $info['base_image'];
561 562 563
  $source = imagecreatefrompng($source);
  $width = imagesx($source);
  $height = imagesy($source);
Steven Wittens's avatar
Steven Wittens committed
564 565

  // Prepare target buffer.
566
  $target = imagecreatetruecolor($width, $height);
567
  imagealphablending($target, TRUE);
568 569 570 571 572 573

  // Fill regions of solid color.
  foreach ($info['fill'] as $color => $fill) {
    imagefilledrectangle($target, $fill[0], $fill[1], $fill[0] + $fill[2], $fill[1] + $fill[3], _color_gd($target, $palette[$color]));
  }

574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590
  // Render gradients.
  foreach ($info['gradients'] as $gradient) {
    // Get direction of the gradient.
    if (isset($gradient['direction']) && $gradient['direction'] == 'horizontal') {
      // Horizontal gradient.
      for ($x = 0; $x < $gradient['dimension'][2]; $x++) {
        $color = _color_blend($target, $palette[$gradient['colors'][0]], $palette[$gradient['colors'][1]], $x / ($gradient['dimension'][2] - 1));
        imagefilledrectangle($target, ($gradient['dimension'][0] + $x), $gradient['dimension'][1], ($gradient['dimension'][0] + $x + 1), ($gradient['dimension'][1] + $gradient['dimension'][3]), $color);
      }
    }
    else {
      // Vertical gradient.
      for ($y = 0; $y < $gradient['dimension'][3]; $y++) {
        $color = _color_blend($target, $palette[$gradient['colors'][0]], $palette[$gradient['colors'][1]], $y / ($gradient['dimension'][3] - 1));
        imagefilledrectangle($target, $gradient['dimension'][0], $gradient['dimension'][1] + $y, $gradient['dimension'][0] + $gradient['dimension'][2], $gradient['dimension'][1] + $y + 1, $color);
      }
    }
591 592
  }

Steven Wittens's avatar
Steven Wittens committed
593
  // Blend over template.
594 595
  imagecopy($target, $source, 0, 0, 0, 0, $width, $height);

Steven Wittens's avatar
Steven Wittens committed
596
  // Clean up template image.
597 598
  imagedestroy($source);

Steven Wittens's avatar
Steven Wittens committed
599
  // Cut out slices.
600 601
  foreach ($info['slices'] as $file => $coord) {
    list($x, $y, $width, $height) = $coord;
602
    $base = drupal_basename($file);
603
    $image = drupal_realpath($paths['target'] . $base);
604

Steven Wittens's avatar
Steven Wittens committed
605
    // Cut out slice.
606 607 608
    if ($file == 'screenshot.png') {
      $slice = imagecreatetruecolor(150, 90);
      imagecopyresampled($slice, $target, 0, 0, $x, $y, 150, 90, $width, $height);
609
      \Drupal::config('color.' . $theme)
610 611
        ->set('screenshot', $image)
        ->save();
612 613 614 615 616 617
    }
    else {
      $slice = imagecreatetruecolor($width, $height);
      imagecopy($slice, $target, 0, 0, $x, $y, $width, $height);
    }

Steven Wittens's avatar
Steven Wittens committed
618
    // Save image.
619 620 621 622
    imagepng($slice, $image);
    imagedestroy($slice);
    $paths['files'][] = $image;

623
    // Set standard file permissions for webserver-generated files
624
    drupal_chmod($image);
625

626 627 628 629
    // Build before/after map of image paths.
    $paths['map'][$file] = $base;
  }

Steven Wittens's avatar
Steven Wittens committed
630
  // Clean up target buffer.
631 632 633 634
  imagedestroy($target);
}

/**
635
 * Shifts a given color, using a reference pair and a target blend color.
636 637 638 639
 *
 * Note: this function is significantly different from the JS version, as it
 * is written to match the blended images perfectly.
 *
640 641
 * Constraint: if (ref2 == target + (ref1 - target) * delta) for some fraction
 * delta then (return == target + (given - target) * delta).
642 643
 *
 * Loose constraint: Preserve relative positions in saturation and luminance
644
 * space.
645 646 647
 */
function _color_shift($given, $ref1, $ref2, $target) {
  // We assume that ref2 is a blend of ref1 and target and find
648
  // delta based on the length of the difference vectors.
649 650

  // delta = 1 - |ref2 - ref1| / |white - ref1|
651 652 653
  $target = _color_unpack($target, TRUE);
  $ref1 = _color_unpack($ref1, TRUE);
  $ref2 = _color_unpack($ref2, TRUE);
654 655
  $numerator = 0;
  $denominator = 0;
656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675
  for ($i = 0; $i < 3; ++$i) {
    $numerator += ($ref2[$i] - $ref1[$i]) * ($ref2[$i] - $ref1[$i]);
    $denominator += ($target[$i] - $ref1[$i]) * ($target[$i] - $ref1[$i]);
  }
  $delta = ($denominator > 0) ? (1 - sqrt($numerator / $denominator)) : 0;

  // Calculate the color that ref2 would be if the assumption was true.
  for ($i = 0; $i < 3; ++$i) {
    $ref3[$i] = $target[$i] + ($ref1[$i] - $target[$i]) * $delta;
  }

  // If the assumption is not true, there is a difference between ref2 and ref3.
  // We measure this in HSL space. Notation: x' = hsl(x).
  $ref2 = _color_rgb2hsl($ref2);
  $ref3 = _color_rgb2hsl($ref3);
  for ($i = 0; $i < 3; ++$i) {
    $shift[$i] = $ref2[$i] - $ref3[$i];
  }

  // Take the given color, and blend it towards the target.
676
  $given = _color_unpack($given, TRUE);
677 678 679 680 681 682 683 684 685 686 687 688 689
  for ($i = 0; $i < 3; ++$i) {
    $result[$i] = $target[$i] + ($given[$i] - $target[$i]) * $delta;
  }

  // Finally, we apply the extra shift in HSL space.
  // Note: if ref2 is a pure blend of ref1 and target, then |shift| = 0.
  $result = _color_rgb2hsl($result);
  for ($i = 0; $i < 3; ++$i) {
    $result[$i] = min(1, max(0, $result[$i] + $shift[$i]));
  }
  $result = _color_hsl2rgb($result);

  // Return hex color.
690
  return _color_pack($result, TRUE);
691 692 693
}

/**
694
 * Converts a hex triplet into a GD color.
695 696 697 698 699 700 701
 */
function _color_gd($img, $hex) {
  $c = array_merge(array($img), _color_unpack($hex));
  return call_user_func_array('imagecolorallocate', $c);
}

/**
702
 * Blends two hex colors and returns the GD color.
703 704 705 706 707 708 709 710
 */
function _color_blend($img, $hex1, $hex2, $alpha) {
  $in1 = _color_unpack($hex1);
  $in2 = _color_unpack($hex2);
  $out = array($img);
  for ($i = 0; $i < 3; ++$i) {
    $out[] = $in1[$i] + ($in2[$i] - $in1[$i]) * $alpha;
  }
711

712 713 714 715
  return call_user_func_array('imagecolorallocate', $out);
}

/**
716
 * Converts a hex color into an RGB triplet.
717
 */
718
function _color_unpack($hex, $normalize = FALSE) {
719 720 721 722 723 724 725
  if (strlen($hex) == 4) {
    $hex = $hex[1] . $hex[1] . $hex[2] . $hex[2] . $hex[3] . $hex[3];
  }
  $c = hexdec($hex);
  for ($i = 16; $i >= 0; $i -= 8) {
    $out[] = (($c >> $i) & 0xFF) / ($normalize ? 255 : 1);
  }
726

727 728 729 730
  return $out;
}

/**
731
 * Converts an RGB triplet to a hex color.
732
 */
733
function _color_pack($rgb, $normalize = FALSE) {
734
  $out = 0;
735 736 737
  foreach ($rgb as $k => $v) {
    $out |= (($v * ($normalize ? 255 : 1)) << (16 - $k * 8));
  }
738

739
  return '#' . str_pad(dechex($out), 6, 0, STR_PAD_LEFT);
740 741 742
}

/**
743
 * Converts an HSL triplet into RGB.
744 745 746 747 748 749 750
 */
function _color_hsl2rgb($hsl) {
  $h = $hsl[0];
  $s = $hsl[1];
  $l = $hsl[2];
  $m2 = ($l <= 0.5) ? $l * ($s + 1) : $l + $s - $l*$s;
  $m1 = $l * 2 - $m2;
751

752 753 754 755 756
  return array(
    _color_hue2rgb($m1, $m2, $h + 0.33333),
    _color_hue2rgb($m1, $m2, $h),
    _color_hue2rgb($m1, $m2, $h - 0.33333),
  );
757 758 759 760 761 762 763 764 765 766
}

/**
 * Helper function for _color_hsl2rgb().
 */
function _color_hue2rgb($m1, $m2, $h) {
  $h = ($h < 0) ? $h + 1 : (($h > 1) ? $h - 1 : $h);
  if ($h * 6 < 1) return $m1 + ($m2 - $m1) * $h * 6;
  if ($h * 2 < 1) return $m2;
  if ($h * 3 < 2) return $m1 + ($m2 - $m1) * (0.66666 - $h) * 6;
767

768 769 770 771
  return $m1;
}

/**
772
 * Converts an RGB triplet to HSL.
773 774 775 776 777 778 779 780 781 782
 */
function _color_rgb2hsl($rgb) {
  $r = $rgb[0];
  $g = $rgb[1];
  $b = $rgb[2];
  $min = min($r, min($g, $b));
  $max = max($r, max($g, $b));
  $delta = $max - $min;
  $l = ($min + $max) / 2;
  $s = 0;
783

784
  if ($l > 0 && $l < 1) {
Steven Wittens's avatar
Steven Wittens committed
785
    $s = $delta / ($l < 0.5 ? (2 * $l) : (2 - 2 * $l));
786
  }
787

788 789
  $h = 0;
  if ($delta > 0) {
Steven Wittens's avatar
Steven Wittens committed
790 791 792 793
    if ($max == $r && $max != $g) $h += ($g - $b) / $delta;
    if ($max == $g && $max != $b) $h += (2 + ($b - $r) / $delta);
    if ($max == $b && $max != $r) $h += (4 + ($r - $g) / $delta);
    $h /= 6;
794
  }
795

796
  return array($h, $s, $l);
797
}