cairoSetDash {RGtk2} | R Documentation

## cairoSetDash

### Description

Sets the dash pattern to be used by `cairoStroke`. A dash pattern is specified by `dashes`, a list of positive values. Each value provides the length of alternate "on" and "off" portions of the stroke. The `offset` specifies an offset into the pattern at which the stroke begins.

### Usage

    cairoSetDash(cr, dashes, offset)

### Arguments

``cr`` | [`Cairo`] a cairo context
``dashes`` | [numeric] a list specifying alternate lengths of on and off stroke portions
``offset`` | [numeric] an offset into the dash pattern at which the stroke should start

### Details

Each "on" segment will have caps applied as if the segment were a separate sub-path. In particular, it is valid to use an "on" length of 0.0 with `CAIRO_LINE_CAP_ROUND` or `CAIRO_LINE_CAP_SQUARE` in order to distributed dots or squares along a path.

Note: The length values are in user-space units as evaluated at the time of stroking. This is not necessarily the same as the user space at the time of `cairoSetDash`.

If `num.dashes` is 0 dashing is disabled.

If `num.dashes` is 1 a symmetric pattern is assumed with alternating on and off portions of the size specified by the single value in `dashes`.

If any value in `dashes` is negative, or if all values are 0, then `cr` will be put into an error state with a status of `CAIRO_STATUS_INVALID_DASH`.

### Author(s)

Derived by RGtkGen from GTK+ documentation

[Package RGtk2 version 2.20.36.3 Index]