R: Combine images using Porter-Duff operations.

feComposite {gridSVG} | R Documentation

## Combine images using Porter-Duff operations.

### Description

This filter performs the combination of the two input images pixel-wise in image space using one of the Porter-Duff compositing operations.

The arithmetic operation is useful for combining the output from the `feDiffuseLighting` and `feSpecularLighting` filter effects with texture data. It is also useful for implementing dissolve.

### Usage

    feComposite(input1 = NA, input2 = NA,
                operator = c("over", "in", "out", "atop",
                             "xor", "arithmetic"),
                k1 = 0, k2 = 0, k3 = 0, k4 = 0, ...)

### Arguments

`input1` | Identifies an input for this filter primtive. See `filterInputs`.
`input2` | Identfies a second input for this filter primitive. See `filterInputs`.
`operator` | The compositing operation that is to be performed. All of the `operator` types except `"arithmetic"` match the corresponding operation as described in the referenced Porter-Duff text. The arithmetic operator is described in the referenced SVG specification.
`k1` | A numeric value. Only applicable if `operator` is `"arithmetic"`.
`k2` | A numeric value. Only applicable if `operator` is `"arithmetic"`.
`k3` | A numeric value. Only applicable if `operator` is `"arithmetic"`.
`k4` | A numeric value. Only applicable if `operator` is `"arithmetic"`.
`...` | Further arguments to be passed onto `fe`.

### Details

For more information about this primitive, consult the reference to the SVG specification.

### Value

An `fe.composite` object.

### Author(s)

Simon Potter

### References

http://www.w3.org/TR/SVG/filters.html#feCompositeElement

Compositing Digital Images, T. Porter and T. Duff. SIGGRAPH '84 Conference Proceedings, Association for Computing Machinery, Volume 18, Number 3, July 1984.

### See Also

`filterEffect`, `fe`.

[Package gridSVG version 1.6-0 Index]