protected static function GdGaussianBlur::ucharClamp in Image Effects 8.2

Same name and namespace in other branches

1. 8.3 src/Component/GdGaussianBlur.php \Drupal\image_effects\Component\GdGaussianBlur::ucharClamp()
2. 8 src/Component/GdGaussianBlur.php \Drupal\image_effects\Component\GdGaussianBlur::ucharClamp()

Convert a double to an unsigned char.

Round to the nearest integer and clamp the result between 0 and max. The absolute value of $clr must be less than the maximum value of an unsigned short. Casting a negative float to an unsigned short is undefined. However, casting a float to a signed truncates toward zero and casting a negative signed value to an unsigned of the same size results in a bit-identical value (assuming twos-complement arithmetic). This is what we want: all legal negative values for $clr will be greater than 255.

Parameters

float $clr: The float to be converted.

int $max: The maximum value.

Return value

int The converted value.

1 call to GdGaussianBlur::ucharClamp()

GdGaussianBlur::applyCoeffsLine in src/Component/GdGaussianBlur.php

Applies the Gaussian coefficients to a line of the destination image.

File

src/Component/GdGaussianBlur.php, line 178

Class

GdGaussianBlur

Gaussian Blur helper methods for GD.

Namespace

Drupal\image_effects\Component

Code

protected static function ucharClamp($clr, $max) {

  // Convert and clamp.
  $result = (int) ($clr + 0.5);
  if ($result > $max) {
    $result = $clr < 0 ? 0 : $max;
  }
  return $result;
}