gdkPixbufAddAlpha {RGtk2} | R Documentation

## gdkPixbufAddAlpha

### Description

Takes an existing pixbuf and adds an alpha channel to it. If the existing pixbuf already had an alpha channel, the channel values are copied from the original; otherwise, the alpha channel is initialized to 255 (full opacity).

### Usage

    gdkPixbufAddAlpha(object, substitute.color, r, g, b)

### Arguments

``object`` | A `GdkPixbuf`.
``substitute.color`` | Whether to set a color to zero opacity. If this is `FALSE`, then the (`r`, `g`, `b`) arguments will be ignored.
``r`` | Red value to substitute.
``g`` | Green value to substitute.
``b`` | Blue value to substitute.

### Details

If `substitute.color` is `TRUE`, then the color specified by (`r`, `g`, `b`) will be assigned zero opacity. That is, if you pass (255, 255, 255) for the substitute color, all white pixels will become fully transparent.

### Value

[`GdkPixbuf`] A newly-created pixbuf with a reference count of 1.

### Author(s)

Derived by RGtkGen from GTK+ documentation

[Package RGtk2 version 2.20.36.3 Index]