isTransparent: Test whether a integer corresponds to the color 'transparent'

In omegahat/RGraphicsDevice: A framework for developing R graphics devices entirely in R

Description

This function takes an R graphics engine color specified as an integer and determines whether this is actually the special color 'transparent'.

Usage

isTransparent(col)

Arguments

col	an integer typically from either the col or fill field in an instance of the R_GE_gcontextPtr type.

Value

A logical value. This is TRUE if the color is the special transparent color.

Author(s)

Duncan Temple Lang

References

“The R Internals Manual”, R Development Core Team.

See Also

R_GE_gcontextPtr

Examples

  isTransparent(-16776961)

  isTransparent(as("transparent", "RGBInt"))
  isTransparent(as("transparent", "RGBInt"))

omegahat/RGraphicsDevice documentation built on Jan. 18, 2022, 4:37 a.m.