image_rotate ( : : Row, Column, Angle : )

Modify the current transformation matrix by a rotation.

image_rotate modifies the current transformation matrix by applying a rotation. The current transformation matrix is used in image_transform__ for an arbitrary affine transformation of an image. The rotation is addeed to any other modifications of the CTM effected by image_scale, image_translate, or image_rotate. If this is not desired, image_identity must be called before calling image_scale. The point (Row,Column) determines the center of the rotation. Angle determines the counterclockwise angle of rotation in radians.


Parameters

Row (input_control)
point.y -> real / integer
Row coordinate of the center of the rotation.
Default value: 256
Suggested values: 0, 128, 256, 512
Range of values: 0 <= Row <= 512
Minimum increment: 1
Recommended increment: 10

Column (input_control)
point.x -> real / integer
Column coordinate of the center of the rotation.
Default value: 256
Suggested values: 0, 128, 256, 512
Range of values: 0 <= Column <= 512
Minimum increment: 1
Recommended increment: 10

Angle (input_control)
angle.rad -> real / integer
Rotation angle (radians).
Default value: 0.7854
Suggested values: 0.7854, 1.5708, 2.3362, 3.1416
Range of values: 0.0 <= Angle <= 3.1416
Minimum increment: 0.001
Recommended increment: 0.1
Restriction: Angle >= 0.0


Example
/* Rotation of an image (512 x 512 image points) by 45 degrees: */
image_identity(:::) >
image_rotate(::256.0,256.0,0.7854:) >
image_transform__(Image:TrafoImage2:1:).

Result

image_rotate returns TRUE if all parameter values are correct. Otherwise, an exception is raised.


Alternatives

rotate_image


See also

image_transform__, image_identity, image_scale, image_translate



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