kernelUnitLength
The kernelUnitLength
attribute has two meanings based on the context it's used in. For lighting filter primitives, it indicates the intended distance for the x and y coordinates, for <feConvolveMatrix>
, it indicates the intended distance between successive columns and rows in the kernel matrix.
You can use this attribute with the following SVG elements:
feConvolveMatrix
For the <feConvolveMatrix>
, kernelUnitLength
indicates the intended distance in current filter units (i.e., units as determined by the value of primitiveUnits
attribute) between successive columns and rows, respectively, in the kernelMatrix
. By specifying value(s) for kernelUnitLength
, the kernel becomes defined in a scalable, abstract coordinate system. If the attribute is not specified, the default value is one pixel in the offscreen bitmap, which is a pixel-based coordinate system, and thus potentially not scalable.
If a negative or zero value is specified the default value will be used instead.
Value |
<number-optional-number>
|
---|---|
Default value | Pixel in offscreen bitmap |
Animatable | Yes |
<number-optional-number>
-
The first number is the x value. The second number is the y value. If the x value is not specified, it defaults to the same value as x.
feDiffuseLighting
For the <feDiffuseLighting>
, kernelUnitLength
indicates the intended distance in current filter units (i.e., units as determined by the value of attribute primitiveUnits
) for the x and y coordinate, respectively, in the surface normal calculation formulas.
The first number is the x value. The second number is the y value. If the y value is not specified, it defaults to the same value as x. By specifying value(s) for kernelUnitLength
, the kernel becomes defined in a scalable, abstract coordinate system. If the attribute is not specified, the x and y values represent very small deltas relative to a given position, which might be implemented in some cases as one pixel in the intermediate image offscreen bitmap, which is a pixel-based coordinate system, and thus potentially not scalable.
If a negative or zero value is specified the default value will be used instead.
Value |
<number-optional-number>
|
---|---|
Default value | Pixel in offscreen bitmap |
Animatable | Yes |
feSpecularLighting
For the <feSpecularLighting>
, kernelUnitLength
indicates the intended distance in current filter units (i.e., units as determined by the value of attribute primitiveUnits
) for the x and y coordinate, respectively, in the surface normal calculation formulas.
The first number is the x value. The second number is the y value. If the y value is not specified, it defaults to the same value as x. By specifying value(s) for kernelUnitLength
, the kernel becomes defined in a scalable, abstract coordinate system. If the attribute is not specified, the x and y values represent very small deltas relative to a given position, which might be implemented in some cases as one pixel in the intermediate image offscreen bitmap, which is a pixel-based coordinate system, and thus potentially not scalable.
If a negative or zero value is specified the default value will be used instead.
Value |
<number-optional-number>
|
---|---|
Default value | Pixel in offscreen bitmap |
Animatable | Yes |