imageaffinematrixget 
RETURNS an affine transformation matrix.
AFFINE
is a geometric transformation operation involving MATRICES, covering both, 2D and 3D environment.
Transformations are often used in linear algebra and computer graphics.
In geometric transformations of images, the pixel coordinate is mapped.
This means that, each pixel is localized by two coordinates, in the rectangular domain of the image.
Without going into more details about pixel mapping, let's get to what really matters: the AFFINE transformations.
There are several classes of pixel mapping, one is called AFFINE.
AFFINE transformations include: scaling, rotation, shearing and translation.
If
$type = IMG_AFFINE_TRANSLATE
or
$type = IMG_AFFINE_SCALE,
$options has to be an ARRAY with keys x and y, both having FLOAT values.
If
$type = IMG_AFFINE_ROTATE, $type = IMG_AFFINE_SHEAR_HORIZONTAL
or
$type = IMG_AFFINE_SHEAR_VERTICAL,
$options has to be a float specifying the angle.
This function returns FALSE on failure.
<?php
array|false imageaffinematrixget ( int $type, array|float $options )
where,
$type = One of the IMG_AFFINE_* constants
( SEE the below TABLE )
$options = An ARRAY with keys x and y,
both having FLOAT values
?>
$type
One of the IMG_AFFINE_* constants.
| VALUE |
CONSTANT |
| 0 |
IMG_AFFINE_TRANSLATE |
| 1 |
IMG_AFFINE_SCALE |
| 2 |
IMG_AFFINE_ROTATE |
| 3 |
IMG_AFFINE_SHEAR_HORIZONTAL |
| 4 |
IMG_AFFINE_SHEAR_VERTICAL |
| ed48 |
$options
Depending on the values entered in $type may be expressed as FLOAT values.
EXERCISE
<?php
echo 'PHP VERSION: ' . PHP_VERSION . '<br><br>';
$img_base = 'png/PNG 087 01.png';
$img_tgt = 'png/PNG 087 01 imageaffinematrixget ';
$arr1 = [ 0, 1, 2, 3, 4.58, 20];
?>
EXISTING IMAGE<br><br>
<img src="<?php echo $img_base; ?>"
alt="<?php echo $img_base; ?>"><br><br>
<?php
$id_aff0 = imagecreatefrompng($img_base);
foreach($arr1 as $a1)
{
$arr_at =
imageaffinematrixget(IMG_AFFINE_SHEAR_VERTICAL, $a1);
$id_aff = imageaffine($id_aff0, $arr_at);
imagepng($id_aff, $img_tgt . $a1 . '.png', 9);
echo '<br><br>RESULTING IMAGE ( ' . $a1 . ' )<br><br>';
print_r($arr_at);
echo '<br><br><img src="' . $img_tgt . $a1 . '.png' .
'"alt="' . $a1 . '"><br><br>';
}
?>
RESULT
EXISTING IMAGE
IMG_AFFINE_SHEAR_VERTICAL
RESULTING IMAGE ( 0 )Array
(
[0] => 1
[1] => 0
[2] => 0
[3] => 1
[4] => 0
[5] => 0
)
RESULTING IMAGE ( 1 )Array
(
[0] => 1
[1] => 0.017455064928218
[2] => 0
[3] => 1
[4] => 0
[5] => 0
)
RESULTING IMAGE ( 2 )Array
(
[0] => 1
[1] => 0.034920769491748
[2] => 0
[3] => 1
[4] => 0
[5] => 0
)
RESULTING IMAGE ( 3 )Array
(
[0] => 1
[1] => 0.052407779283041
[2] => 0
[3] => 1
[4] => 0
[5] => 0
)
RESULTING IMAGE ( 4.58 )Array
(
[0] => 1
[1] => 0.080106773937536
[2] => 0
[3] => 1
[4] => 0
[5] => 0
)
RESULTING IMAGE ( 20 )Array
(
[0] => 1
[1] => 0.3639702342662
[2] => 0
[3] => 1
[4] => 0
[5] => 0
)
EXERCISE
<?php
echo 'PHP VERSION: ' . PHP_VERSION . '<br><br>';
$img_base = 'png/PNG 087 02.png';
$img_tgt = 'png/PNG 087 02 imageaffinematrixget ';
$arr1 = [ 0, 1, 2, 3, 4.58, 20];
?>
EXISTING IMAGE<br><br>
<img src="<?php echo $img_base; ?>"
alt="<?php echo $img_base; ?>"><br><br>
<?php
$id_aff0 = imagecreatefrompng($img_base);
foreach($arr1 as $a1)
{
$arr_at =
imageaffinematrixget(IMG_AFFINE_SHEAR_HORIZONTAL, $a1);
$id_aff = imageaffine($id_aff0, $arr_at);
imagepng($id_aff, $img_tgt . $a1 . '.png', 9);
echo '<br><br>RESULTING IMAGE ( ' . $a1 . ' )<br><br>';
print_r($arr_at);
echo '<br><br><img src="' . $img_tgt . $a1 . '.png' .
'"alt="' . $a1 . '"><br><br>';
}
?>
RESULT EXISTING IMAGE
IMG_AFFINE_SHEAR_HORIZONTAL
RESULTING IMAGE ( 0 )Array
(
[0] => 1
[1] => 0
[2] => 0
[3] => 1
[4] => 0
[5] => 0
)
RESULTING IMAGE ( 1 )Array
(
[0] => 1
[1] => 0
[2] => 0.017455064928218
[3] => 1
[4] => 0
[5] => 0
)
RESULTING IMAGE ( 2 )Array
(
[0] => 1
[1] => 0
[2] => 0.034920769491748
[3] => 1
[4] => 0
[5] => 0
)
RESULTING IMAGE ( 3 )Array
(
[0] => 1
[1] => 0
[2] => 0.052407779283041
[3] => 1
[4] => 0
[5] => 0
)
RESULTING IMAGE ( 4.58 )Array
(
[0] => 1
[1] => 0
[2] => 0.080106773937536
[3] => 1
[4] => 0
[5] => 0
)
RESULTING IMAGE ( 20 )Array
(
[0] => 1
[1] => 0
[2] => 0.3639702342662
[3] => 1
[4] => 0
[5] => 0
)
EXERCISE
<?php
echo 'PHP VERSION: ' . PHP_VERSION . '<br><br>';
$img_base = 'png/PNG 085 02.png';
$img_tgt = 'png/PNG 085 03 imageaffinematrixget ';
$arr1 = [ 0, 10, 20, 30, -40.58, 90];
?>
EXISTING IMAGE<br><br>
<img src="<?php echo $img_base; ?>"
alt="<?php echo $img_base; ?>"><br><br>
<?php
$id_aff0 = imagecreatefrompng($img_base);
foreach($arr1 as $a1)
{
$arr_at =
imageaffinematrixget(IMG_AFFINE_ROTATE, $a1);
$id_aff = imageaffine($id_aff0, $arr_at);
imagepng($id_aff, $img_tgt . $a1 . '.png', 9);
echo '<br><br>' . basename($img_tgt);
echo " ( $a1 )<br><br>";
print_r($arr_at);
echo '<br><br><img src="' . $img_tgt . $a1 . '.png' .
'"alt="' . $a1 . '"><br><br>';
}
?>
RESULT EXISTING IMAGE
IMG_AFFINE_ROTATE
PNG 085 03 imageaffinematrixget ( 0 )Array
(
[0] => 1
[1] => 0
[2] => -0
[3] => 1
[4] => 0
[5] => 0
)
PNG 085 03 imageaffinematrixget ( 10 )Array
(
[0] => 0.98480775301221
[1] => 0.17364817766693
[2] => -0.17364817766693
[3] => 0.98480775301221
[4] => 0
[5] => 0
)
PNG 085 03 imageaffinematrixget ( 20 )Array
(
[0] => 0.93969262078591
[1] => 0.34202014332567
[2] => -0.34202014332567
[3] => 0.93969262078591
[4] => 0
[5] => 0
)
PNG 085 03 imageaffinematrixget ( 30 )Array
(
[0] => 0.86602540378444
[1] => 0.5
[2] => -0.5
[3] => 0.86602540378444
[4] => 0
[5] => 0
)
PNG 085 03 imageaffinematrixget ( -40.58 )Array
(
[0] => 0.75949842412838
[1] => -0.65050914193922
[2] => 0.65050914193922
[3] => 0.75949842412838
[4] => 0
[5] => 0
)
PNG 085 03 imageaffinematrixget ( 90 )Array
(
[0] => 6.1232339957368E-17
[1] => 1
[2] => -1
[3] => 6.1232339957368E-17
[4] => 0
[5] => 0
)
