/**
* {@inheritdoc}
*/
protected function validateArguments(array $arguments)
{
// Assure color is a valid hex string.
if (!Color::validateHex($arguments['RGB'])) {
throw new \InvalidArgumentException("Invalid color ('{$arguments['RGB']}') specified for the image 'colorshift' operation");
}
return $arguments;
}
/**
* Convert a RGBA hex to its RGBA integer GD components.
*
* GD expects a value between 0 and 127 for alpha, where 0 indicates
* completely opaque while 127 indicates completely transparent.
* RGBA hexadecimal notation has #00 for transparent and #FF for
* fully opaque.
*
* @param string $rgba_hex
* A string specifing an RGBA color in the format '#RRGGBBAA'.
*
* @return array
* An array with four elements for red, green, blue, and alpha.
*/
protected function hexToRgba($rgba_hex)
{
$rgbHex = Unicode::substr($rgba_hex, 0, 7);
try {
$rgb = Color::hexToRgb($rgbHex);
$opacity = ColorUtility::rgbaToOpacity($rgba_hex);
$alpha = 127 - floor($opacity / 100 * 127);
$rgb['alpha'] = $alpha;
return $rgb;
} catch (\InvalidArgumentException $e) {
return FALSE;
}
}
/**
* Determine best match to over/underlay a defined color.
*
* Calculates UCCIR 601 luma of the entered color and returns a black or
* white color to ensure readibility.
*
* @see http://en.wikipedia.org/wiki/Luma_video
*/
public static function matchLuma($rgba, $soft = FALSE)
{
$rgb = Unicode::substr($rgba, 0, 7);
list($r, $g, $b) = array_values(Color::hexToRgb($rgb));
$luma = 1 - (0.299 * $r + 0.587 * $g + 0.114 * $b) / 255;
if ($luma < 0.5) {
// Bright colors - black.
$d = 0;
} else {
// Dark colors - white.
$d = 255;
}
return Color::rgbToHex(array($d, $d, $d));
}
/**
* Form element validation handler for #type 'color'.
*/
public static function validateColor(&$element, FormStateInterface $form_state, &$complete_form)
{
$value = trim($element['#value']);
// Default to black if no value is given.
// @see http://www.w3.org/TR/html5/number-state.html#color-state
if ($value === '') {
$form_state->setValueForElement($element, '#000000');
} else {
// Try to parse the value and normalize it.
try {
$form_state->setValueForElement($element, ColorUtility::rgbToHex(ColorUtility::hexToRgb($value)));
} catch (\InvalidArgumentException $e) {
$form_state->setError($element, t('%name must be a valid color.', array('%name' => empty($element['#title']) ? $element['#parents'][0] : $element['#title'])));
}
}
}
/**
* {@inheritdoc}
*/
protected function execute(array $arguments)
{
// Get the image type.
$type = $this->getToolkit()->extensionToImageType($arguments['extension']);
// Store the original GD resource.
$original_res = $this->getToolkit()->getResource();
// Create the resource.
if (!($res = imagecreatetruecolor($arguments['width'], $arguments['height']))) {
return FALSE;
}
// Fill the resource with transparency as possible.
switch ($type) {
case IMAGETYPE_PNG:
imagealphablending($res, FALSE);
$transparency = imagecolorallocatealpha($res, 0, 0, 0, 127);
imagefill($res, 0, 0, $transparency);
imagealphablending($res, TRUE);
imagesavealpha($res, TRUE);
break;
case IMAGETYPE_GIF:
if (empty($arguments['transparent_color'])) {
// No transparency color specified, fill white.
$fill_color = imagecolorallocate($res, 255, 255, 255);
} else {
$fill_rgb = Color::hexToRgb($arguments['transparent_color']);
$fill_color = imagecolorallocate($res, $fill_rgb['red'], $fill_rgb['green'], $fill_rgb['blue']);
imagecolortransparent($res, $fill_color);
}
imagefill($res, 0, 0, $fill_color);
break;
case IMAGETYPE_JPEG:
imagefill($res, 0, 0, imagecolorallocate($res, 255, 255, 255));
break;
}
// Update the toolkit properties.
$this->getToolkit()->setType($type);
$this->getToolkit()->setResource($res);
// Destroy the original resource if it is not needed by other operations.
if (!$arguments['is_temp'] && is_resource($original_res)) {
imagedestroy($original_res);
}
return TRUE;
}
/**
* {@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']) + array('alpha' => 0);
} else {
// Background color is not specified: use transparent white as background.
$background = array('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 $arguments;
}
/**
* Gets the color set for transparency in GIF images.
*
* @return string|null
* A color string like '#rrggbb', or NULL if not set or not relevant.
*/
public function getTransparentColor()
{
if (!$this->getResource() || $this->getType() != IMAGETYPE_GIF) {
return NULL;
}
// Find out if a transparent color is set, will return -1 if no
// transparent color has been defined in the image.
$transparent = imagecolortransparent($this->getResource());
if ($transparent >= 0) {
// Find out the number of colors in the image palette. It will be 0 for
// truecolor images.
$palette_size = imagecolorstotal($this->getResource());
if ($palette_size == 0 || $transparent < $palette_size) {
// Return the transparent color, either if it is a truecolor image
// or if the transparent color is part of the palette.
// Since the index of the transparent color is a property of the
// image rather than of the palette, it is possible that an image
// could be created with this index set outside the palette size.
// (see http://stackoverflow.com/a/3898007).
$rgb = imagecolorsforindex($this->getResource(), $transparent);
unset($rgb['alpha']);
return Color::rgbToHex($rgb);
}
}
return NULL;
}
/**
* {@inheritdoc}
*/
public function validateConfigurationForm(array &$form, FormStateInterface $form_state)
{
if (!$form_state->isValueEmpty('bgcolor') && !Color::validateHex($form_state->getValue('bgcolor'))) {
$form_state->setErrorByName('bgcolor', $this->t('Background color must be a hexadecimal color value.'));
}
}
/**
* {@inheritdoc}
*/
protected function execute(array $arguments)
{
$rgb = Color::hexToRgb($arguments['RGB']);
return imagefilter($this->getToolkit()->getResource(), IMG_FILTER_COLORIZE, $rgb['red'], $rgb['green'], $rgb['blue']);
}
/**
* Tests Color::rgbToHex().
*
* @param string $value
* The rgb color value.
* @param string $expected
* The expected hex color value.
*
* @dataProvider providerTestRbgToHex
*/
public function testRgbToHex($value, $expected)
{
$this->assertSame($expected, Color::rgbToHex($value));
}
