Modify the current transformation matrix by a scaling.
image_scale modifies the current transformation matrix by applying a scaling. The current transformation matrix is used in image_transform__ for an arbitrary affine transformation of an image. The scaling 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 scaling. ScaleHeight and ScaleWidth determine the vertical and horizontal scale factors, respectively.
Row (input_control) |
point.y -> real / integer |
Row coordinate of the center of the scaling. | |
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 scaling. | |
Default value: 256 | |
Suggested values: 0, 128, 256, 512 | |
Range of values: 0 <= Column <= 512 | |
Minimum increment: 1 | |
Recommended increment: 10 |
ScaleHeight (input_control) |
extent.y -> real / integer |
Vertical scale factor. | |
Default value: 0.5 | |
Suggested values: 0.25, 0.5, 1.0, 1.0, 2.0, 3.0 | |
Range of values: 0.001 <= ScaleHeight <= 10.0 | |
Minimum increment: 0.001 | |
Recommended increment: 0.1 | |
Restriction: ScaleHeight > 0.0 |
ScaleWidth (input_control) |
extent.x -> real / integer |
Horizontal scale factor. | |
Default value: 0.5 | |
Suggested values: 0.25, 0.5, 1.0, 1.0, 2.0, 3.0 | |
Range of values: 0.001 <= ScaleWidth <= 10.0 | |
Minimum increment: 0.001 | |
Recommended increment: 0.1 | |
Restriction: ScaleWidth > 0.0 |
/* Reduction of an image (512 x 512 image points) by 50%: */ image_identity(:::) > image_scale(::0.0,0.0,0.5,0.5:) > image_transform__(Image:TrafoImage:1:).
image_scale returns TRUE if all parameter values are correct. Otherwise, an exception is raised.
image_transform__, image_rotate, image_translate