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 48 49 50 51
      '#title' => t('Color scheme'),
      '#weight' => -1,
      '#attributes' => array('id' => 'color_scheme_form'),
      '#theme' => 'color_scheme_form',
    );
52
    $form['color'] += color_scheme_form($form, $form_state, $theme);
53
    $form['#validate'][] = 'color_scheme_form_validate';
54
    $form['#submit'][] = 'color_scheme_form_submit';
55
  }
56 57
}

58
/**
59
 * Implements hook_css_alter().
60
 *
61
 * Replaces style sheets with color-altered style sheets.
62
 */
63
function color_css_alter(&$css) {
64
  global $theme_key;
65
  $themes = list_themes();
66 67

  // Override stylesheets.
68
  $color_paths = \Drupal::config('color.' . $theme_key)->get('stylesheets');
69 70

  if (!empty($color_paths) && !empty($themes[$theme_key]->stylesheets['all'])) {
71

72
    foreach ($themes[$theme_key]->stylesheets['all'] as $old_path) {
73 74 75 76 77
      // Loop over the path array with recolored CSS files to find matching
      // paths which could replace the non-recolored paths.
      foreach ($color_paths as $color_path) {
        // Color module currently requires unique file names to be used,
        // which allows us to compare different file paths.
78
        if (drupal_basename($old_path) == drupal_basename($color_path)) {
79 80
          // Replace the path to the new css file.
          // This keeps the order of the stylesheets intact.
81
          $css[drupal_basename($old_path)]['data'] = $color_path;
82 83 84
        }
      }
    }
85
  }
86 87 88
}

/**
89
 * Implements hook_preprocess_page().
90
 *
91
 * Replace the logo with the colored version if available.
92
 */
93
function color_preprocess_page(&$variables) {
94
  global $theme_key;
95

96
  // Override logo.
97
  $logo = \Drupal::config('color.' . $theme_key)->get('logo');
98 99
  if ($logo && $variables['logo'] && preg_match('!' . $theme_key . '/logo.png$!', $variables['logo'])) {
    $variables['logo'] = file_create_url($logo);
100 101 102 103
  }
}

/**
104
 * Retrieves the Color module information for a particular theme.
105 106
 */
function color_get_info($theme) {
107 108 109 110 111 112
  static $theme_info = array();

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

113
  $path = drupal_get_path('theme', $theme);
114
  $file = DRUPAL_ROOT . '/' . $path . '/color/color.inc';
115 116
  if ($path && file_exists($file)) {
    include $file;
117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132
    // 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',
    );
133
    $theme_info[$theme] = $info;
134 135 136 137 138
    return $info;
  }
}

/**
139
 * Retrieves the color palette for a particular theme.
140
 */
141
function color_get_palette($theme, $default = FALSE) {
142
  // Fetch and expand default palette.
143
  $info = color_get_info($theme);
144
  $palette = $info['schemes']['default']['colors'];
145

146 147 148 149
  if ($default) {
    return $palette;
  }

150
  // Load variable.
151
  // @todo Default color config should be moved to yaml in the theme.
152
  return \Drupal::config('color.' . $theme)->get('palette') ?: $palette;
153 154 155
}

/**
156 157 158 159 160 161 162 163
 * Form constructor for the color configuration form for a particular theme.
 *
 * @param $theme
 *   The machine name of the theme whose color settings are being configured.
 *
 * @see color_scheme_form_validate()
 * @see color_scheme_form_submit()
 * @ingroup forms
164
 */
165
function color_scheme_form($complete_form, &$form_state, $theme) {
166 167 168
  $base = drupal_get_path('module', 'color');
  $info = color_get_info($theme);

169 170 171 172 173 174 175 176 177
  $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'];
  }

178
  // See if we're using a predefined scheme.
179
  // Note: we use the original theme when the default scheme is chosen.
180
  $current_scheme = \Drupal::config('color.' . $theme)->get('palette');
181 182 183 184 185 186 187 188 189 190 191 192 193 194
  foreach ($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 = '';
    }
  }
195

196
  // Add scheme selector.
197 198 199
  $form['scheme'] = array(
    '#type' => 'select',
    '#title' => t('Color set'),
200 201
    '#options' => $color_sets,
    '#default_value' => $scheme_name,
202 203
    '#attached' => array(
      'library' => array(
204
        array('color', 'drupal.color'),
205 206 207
      ),
      // Add custom CSS.
      'css' => array(
208
        $base . '/css/color.admin.css' => array(),
209 210 211 212 213
      ),
      // Add custom JavaScript.
      'js' => array(
        array(
          'data' => array(
214 215 216 217 218
            'color' => array(
              'reference' => color_get_palette($theme, TRUE),
              'schemes' => $schemes,
            ),
            'gradients' => $info['gradients'],
219 220 221
          ),
          'type' => 'setting',
        ),
222 223
      ),
    ),
224 225
  );

226
  // Add palette fields.
227
  $palette = color_get_palette($theme);
228
  $names = $info['fields'];
229
  $form['palette']['#tree'] = TRUE;
230
  foreach ($palette as $name => $value) {
231 232 233
    if (isset($names[$name])) {
      $form['palette'][$name] = array(
        '#type' => 'textfield',
234
        '#title' => String::checkPlain($names[$name]),
235
        '#value_callback' => 'color_palette_color_value',
236 237
        '#default_value' => $value,
        '#size' => 8,
238
        '#attributes' => array('dir' => 'ltr'),
239 240
      );
    }
241
  }
242
  $form['theme'] = array('#type' => 'value', '#value' => $theme);
243 244 245 246 247 248
  $form['info'] = array('#type' => 'value', '#value' => $info);

  return $form;
}

/**
249
 * Prepares variables for color scheme form templates.
250
 *
251 252 253
 * Default template: color-scheme-form.html.twig.
 *
 * @param array $variables
254 255
 *   An associative array containing:
 *   - form: A render element representing the form.
256
 */
257
function template_preprocess_color_scheme_form(&$variables) {
258
  $form = &$variables['form'];
259

260 261
  $theme = $form['theme']['#value'];
  $info = $form['info']['#value'];
262
  $path = drupal_get_path('theme', $theme) . '/';
263

264 265 266 267
  if (isset($info['preview_css'])) {
    $preview_css_path = $path . $info['preview_css'];
    $form['scheme']['#attached']['css'][$preview_css_path] = array();
  }
268 269
  $preview_js_path = isset($info['preview_js']) ? $path . $info['preview_js'] : drupal_get_path('module', 'color') . '/' . 'preview.js';
  // Add the JS at a weight below color.js.
270
  $form['scheme']['#attached']['js'][$preview_js_path] = array('weight' => -1);
271

272 273
  // 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');
274
  $variables['html_preview'] = file_get_contents($preview_html_path);
275 276
}

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
/**
 * 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);
}

323
/**
324 325 326
 * Form validation handler for color_scheme_form().
 *
 * @see color_scheme_form_submit()
327 328 329 330
 */
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 => $color) {
331
    if (!color_valid_hexadecimal_string($color)) {
332
      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'])));
333 334 335 336
    }
  }
}

337
/**
338 339 340
 * Form submission handler for color_scheme_form().
 *
 * @see color_scheme_form_validate()
341
 */
342
function color_scheme_form_submit($form, &$form_state) {
343

344
  // Get theme coloring info.
345
  if (!isset($form_state['values']['info'])) {
346 347
    return;
  }
348 349
  $theme = $form_state['values']['theme'];
  $info = $form_state['values']['info'];
350

351
  $config = \Drupal::config('color.' . $theme);
352

353
  // Resolve palette.
354 355
  $palette = $form_state['values']['palette'];
  if ($form_state['values']['scheme'] != '') {
356 357 358 359
    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];
      }
360
    }
361
    $palette += $info['schemes']['default']['colors'];
362 363
  }

364
  // Make sure enough memory is available.
365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383
  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;
    }
384 385
  }

386
  // Delete old files.
387 388 389 390 391
  $files = $config->get('files');
  if (isset($files)) {
    foreach ($files as $file) {
      @drupal_unlink($file);
    }
392
  }
393
  if (isset($file) && $file = dirname($file)) {
394
    @drupal_rmdir($file);
395 396
  }

397
  // No change in color config, use the standard theme from color.inc.
398
  if (implode(',', color_get_palette($theme, TRUE)) == implode(',', $palette)) {
399
    $config->delete();
400 401 402
    return;
  }

403
  // Prepare target locations for generated files.
404
  $id = $theme . '-' . substr(hash('sha256', serialize($palette) . microtime()), 0, 8);
405
  $paths['color'] = file_default_scheme() . '://color';
406
  $paths['target'] = $paths['color'] . '/' . $id;
407
  foreach ($paths as $path) {
408
    file_prepare_directory($path, FILE_CREATE_DIRECTORY);
409
  }
410
  $paths['target'] = $paths['target'] . '/';
411
  $paths['id'] = $id;
412
  $paths['source'] = drupal_get_path('theme', $theme) . '/';
413 414
  $paths['files'] = $paths['map'] = array();

415
  // Save palette and logo location.
416 417 418 419
  $config
    ->set('palette', $palette)
    ->set('logo', $paths['target'] . 'logo.png')
    ->save();
420

421
  // Copy over neutral images.
422
  foreach ($info['copy'] as $file) {
423
    $base = drupal_basename($file);
424
    $source = $paths['source'] . $file;
425
    $filepath = file_unmanaged_copy($source, $paths['target'] . $base);
426
    $paths['map'][$file] = $base;
427
    $paths['files'][] = $filepath;
428 429
  }

430
  // Render new images, if image has been provided.
431
  if (isset($info['base_image'])) {
432 433
    _color_render_images($theme, $info, $paths, $palette);
  }
434

435 436 437
  // Rewrite theme stylesheets.
  $css = array();
  foreach ($info['css'] as $stylesheet) {
438
    // Build a temporary array with CSS files.
439 440 441 442 443 444
    $files = array();
    if (file_exists($paths['source'] . $stylesheet)) {
      $files[] = $stylesheet;
    }

    foreach ($files as $file) {
445
      $css_optimizer = new CssOptimizer();
446 447
      // Aggregate @imports recursively for each configured top level CSS file
      // without optimization. Aggregation and optimization will be
448
      // handled by drupal_build_css_cache() only.
449
      $style = $css_optimizer->loadFile($paths['source'] . $file, FALSE);
450 451 452

      // Return the path to where this CSS file originated from, stripping
      // off the name of the file at the end of the path.
453
      $css_optimizer->rewriteFileURIBasePath = base_path() . dirname($paths['source'] . $file) . '/';
454 455

      // Prefix all paths within this CSS file, ignoring absolute paths.
456
      $style = preg_replace_callback('/url\([\'"]?(?![a-z]+:|\/+)([^\'")]+)[\'"]?\)/i', array($css_optimizer, 'rewriteFileURI'), $style);
457 458 459

      // Rewrite stylesheet with new colors.
      $style = _color_rewrite_stylesheet($theme, $info, $paths, $palette, $style);
460
      $base_file = drupal_basename($file);
461 462
      $css[] = $paths['target'] . $base_file;
      _color_save_stylesheet($paths['target'] . $base_file, $style, $paths);
463
    }
464
  }
465

466
  // Maintain list of files.
467 468 469 470
  $config
    ->set('stylesheets', $css)
    ->set('files', $paths['files'])
    ->save();
471 472 473
}

/**
474
 * Rewrites the stylesheet to match the colors in the palette.
475
 */
476
function _color_rewrite_stylesheet($theme, &$info, &$paths, $palette, $style) {
477
  // Prepare color conversion table.
478 479 480 481
  $conversion = $palette;
  foreach ($conversion as $k => $v) {
    $conversion[$k] = drupal_strtolower($v);
  }
482
  $default = color_get_palette($theme, TRUE);
483 484

  // Split off the "Don't touch" section of the stylesheet.
485
  $split = "Color Module: Don't touch";
486
  if (strpos($style, $split) !== FALSE) {
487 488
    list($style, $fixed) = explode($split, $style);
  }
489 490 491

  // 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);
492
  $is_color = FALSE;
493 494 495
  $output = '';
  $base = 'base';

496
  // Iterate over all the parts.
497 498 499
  foreach ($style as $chunk) {
    if ($is_color) {
      $chunk = drupal_strtolower($chunk);
500
      // Check if this is one of the colors in the default palette.
501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516
      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)) {
        $base = 'link';
      }
      // 'color:' styles. Use text.
517
      elseif (preg_match('/(?<!-)color[^{:]*:[^{#]*$/i', $chunk)) {
518 519 520 521 522 523 524 525 526 527
        $base = 'text';
      }
      // Reset back to base.
      else {
        $base = 'base';
      }
    }
    $output .= $chunk;
    $is_color = !$is_color;
  }
528 529 530 531
  // Append fixed colors segment.
  if (isset($fixed)) {
    $output .= $fixed;
  }
532

533
  // Replace paths to images.
534
  foreach ($paths['map'] as $before => $after) {
535 536
    $before = base_path() . $paths['source'] . $before;
    $before = preg_replace('`(^|/)(?!../)([^/]+)/../`', '$1', $before);
537 538 539
    $output = str_replace($before, $after, $output);
  }

540
  return $output;
541 542 543
}

/**
544
 * Saves the rewritten stylesheet to disk.
545
 */
546
function _color_save_stylesheet($file, $style, &$paths) {
547
  $filepath = file_unmanaged_save_data($style, $file, FILE_EXISTS_REPLACE);
548
  $paths['files'][] = $filepath;
549 550

  // Set standard file permissions for webserver-generated files.
551
  drupal_chmod($file);
552 553 554
}

/**
555
 * Renders images that match a given palette.
556 557
 */
function _color_render_images($theme, &$info, &$paths, $palette) {
Steven Wittens's avatar
Steven Wittens committed
558
  // Prepare template image.
559
  $source = $paths['source'] . '/' . $info['base_image'];
560 561 562
  $source = imagecreatefrompng($source);
  $width = imagesx($source);
  $height = imagesy($source);
Steven Wittens's avatar
Steven Wittens committed
563 564

  // Prepare target buffer.
565
  $target = imagecreatetruecolor($width, $height);
566
  imagealphablending($target, TRUE);
567 568 569 570 571 572

  // 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]));
  }

573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589
  // 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);
      }
    }
590 591
  }

Steven Wittens's avatar
Steven Wittens committed
592
  // Blend over template.
593 594
  imagecopy($target, $source, 0, 0, 0, 0, $width, $height);

Steven Wittens's avatar
Steven Wittens committed
595
  // Clean up template image.
596 597
  imagedestroy($source);

Steven Wittens's avatar
Steven Wittens committed
598
  // Cut out slices.
599 600
  foreach ($info['slices'] as $file => $coord) {
    list($x, $y, $width, $height) = $coord;
601
    $base = drupal_basename($file);
602
    $image = drupal_realpath($paths['target'] . $base);
603

Steven Wittens's avatar
Steven Wittens committed
604
    // Cut out slice.
605 606 607
    if ($file == 'screenshot.png') {
      $slice = imagecreatetruecolor(150, 90);
      imagecopyresampled($slice, $target, 0, 0, $x, $y, 150, 90, $width, $height);
608
      \Drupal::config('color.' . $theme)
609 610
        ->set('screenshot', $image)
        ->save();
611 612 613 614 615 616
    }
    else {
      $slice = imagecreatetruecolor($width, $height);
      imagecopy($slice, $target, 0, 0, $x, $y, $width, $height);
    }

Steven Wittens's avatar
Steven Wittens committed
617
    // Save image.
618 619 620 621
    imagepng($slice, $image);
    imagedestroy($slice);
    $paths['files'][] = $image;

622
    // Set standard file permissions for webserver-generated files
623
    drupal_chmod($image);
624

625 626 627 628
    // Build before/after map of image paths.
    $paths['map'][$file] = $base;
  }

Steven Wittens's avatar
Steven Wittens committed
629
  // Clean up target buffer.
630 631 632 633
  imagedestroy($target);
}

/**
634
 * Shifts a given color, using a reference pair and a target blend color.
635 636 637 638
 *
 * Note: this function is significantly different from the JS version, as it
 * is written to match the blended images perfectly.
 *
639 640
 * Constraint: if (ref2 == target + (ref1 - target) * delta) for some fraction
 * delta then (return == target + (given - target) * delta).
641 642
 *
 * Loose constraint: Preserve relative positions in saturation and luminance
643
 * space.
644 645 646
 */
function _color_shift($given, $ref1, $ref2, $target) {
  // We assume that ref2 is a blend of ref1 and target and find
647
  // delta based on the length of the difference vectors.
648 649

  // delta = 1 - |ref2 - ref1| / |white - ref1|
650 651 652
  $target = _color_unpack($target, TRUE);
  $ref1 = _color_unpack($ref1, TRUE);
  $ref2 = _color_unpack($ref2, TRUE);
653 654
  $numerator = 0;
  $denominator = 0;
655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674
  for ($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.
675
  $given = _color_unpack($given, TRUE);
676 677 678 679 680 681 682 683 684 685 686 687 688
  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.
689
  return _color_pack($result, TRUE);
690 691 692
}

/**
693
 * Converts a hex triplet into a GD color.
694 695 696 697 698 699 700
 */
function _color_gd($img, $hex) {
  $c = array_merge(array($img), _color_unpack($hex));
  return call_user_func_array('imagecolorallocate', $c);
}

/**
701
 * Blends two hex colors and returns the GD color.
702 703 704 705 706 707 708 709
 */
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;
  }
710

711 712 713 714
  return call_user_func_array('imagecolorallocate', $out);
}

/**
715
 * Converts a hex color into an RGB triplet.
716
 */
717
function _color_unpack($hex, $normalize = FALSE) {
718 719 720 721 722 723 724
  if (strlen($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);
  }
725

726 727 728 729
  return $out;
}

/**
730
 * Converts an RGB triplet to a hex color.
731
 */
732
function _color_pack($rgb, $normalize = FALSE) {
733
  $out = 0;
734 735 736
  foreach ($rgb as $k => $v) {
    $out |= (($v * ($normalize ? 255 : 1)) << (16 - $k * 8));
  }
737

738
  return '#' . str_pad(dechex($out), 6, 0, STR_PAD_LEFT);
739 740 741
}

/**
742
 * Converts an HSL triplet into RGB.
743 744 745 746 747 748 749
 */
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;
750

751 752 753 754 755
  return array(
    _color_hue2rgb($m1, $m2, $h + 0.33333),
    _color_hue2rgb($m1, $m2, $h),
    _color_hue2rgb($m1, $m2, $h - 0.33333),
  );
756 757 758 759 760 761 762 763 764 765
}

/**
 * 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;
766

767 768 769 770
  return $m1;
}

/**
771
 * Converts an RGB triplet to HSL.
772 773 774 775 776 777 778 779 780 781
 */
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;
782

783
  if ($l > 0 && $l < 1) {
Steven Wittens's avatar
Steven Wittens committed
784
    $s = $delta / ($l < 0.5 ? (2 * $l) : (2 - 2 * $l));
785
  }
786

787 788
  $h = 0;
  if ($delta > 0) {
Steven Wittens's avatar
Steven Wittens committed
789 790 791 792
    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;
793
  }
794

795
  return array($h, $s, $l);
796
}