function Rectangle::rotate
Same name in other branches
- 9 core/lib/Drupal/Component/Utility/Rectangle.php \Drupal\Component\Utility\Rectangle::rotate()
- 8.9.x core/lib/Drupal/Component/Utility/Rectangle.php \Drupal\Component\Utility\Rectangle::rotate()
- 10 core/lib/Drupal/Component/Utility/Rectangle.php \Drupal\Component\Utility\Rectangle::rotate()
Rotates the rectangle.
Parameters
float $angle: Rotation angle.
Return value
$this
File
-
core/
lib/ Drupal/ Component/ Utility/ Rectangle.php, line 83
Class
- Rectangle
- Rectangle rotation algebra class.
Namespace
Drupal\Component\UtilityCode
public function rotate($angle) {
// PHP 5.5 GD bug: https://bugs.php.net/bug.php?id=65148: To prevent buggy
// behavior on negative multiples of 30 degrees we convert any negative
// angle to a positive one between 0 and 360 degrees.
$angle -= floor($angle / 360) * 360;
// For some rotations that are multiple of 30 degrees, we need to correct
// an imprecision between GD that uses C floats internally, and PHP that
// uses C doubles. Also, for rotations that are not multiple of 90 degrees,
// we need to introduce a correction factor of 0.5 to match the GD
// algorithm used in PHP 5.5 (and above) to calculate the width and height
// of the rotated image.
if ((int) $angle == $angle && $angle % 90 == 0) {
$imprecision = 0;
$correction = 0;
}
else {
$imprecision = -1.0E-5;
$correction = 0.5;
}
// Do the trigonometry, applying imprecision fixes where needed.
$rad = deg2rad($angle);
$cos = cos($rad);
$sin = sin($rad);
$a = $this->width * $cos;
$b = $this->height * $sin + $correction;
$c = $this->width * $sin;
$d = $this->height * $cos + $correction;
if ((int) $angle == $angle && in_array($angle, [
60,
150,
300,
])) {
$a = $this->fixImprecision($a, $imprecision);
$b = $this->fixImprecision($b, $imprecision);
$c = $this->fixImprecision($c, $imprecision);
$d = $this->fixImprecision($d, $imprecision);
}
// This is how GD on PHP5.5 calculates the new dimensions.
$this->boundingWidth = abs((int) $a) + abs((int) $b);
$this->boundingHeight = abs((int) $c) + abs((int) $d);
return $this;
}
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