// NewBackground creates an xgraphics.Image which spans the entire screen,
// initialized to black.
func NewBackground(X *xgbutil.XUtil) (*xgraphics.Image, error) {
res, err := randr.GetScreenResources(X.Conn(), X.RootWin()).Reply()
if err != nil {
return nil, err
}
var bgRect image.Rectangle
for _, output := range res.Outputs {
r, err := util.OutputRect(X, output)
// NOTE: It doesn't really matter if this returns a Zero Rectangle.
if err != nil {
return nil, err
}
bgRect = bgRect.Union(r)
}
return xgraphics.New(X, bgRect), nil
}
// SetImageToBg sets the given image into the background at the proper location
// for the named output to display.
func SetImageToBg(X *xgbutil.XUtil,
bg *xgraphics.Image,
img image.Image,
name string) error {
output, err := util.GetOutputByName(X, name)
if err != nil {
return err
}
geom, err := util.OutputRect(X, output)
if err != nil {
return err
}
if err = bg.CreatePixmap(); err != nil {
return err
}
bg.XDraw()
draw.Draw(bg, geom, img, img.Bounds().Min, draw.Src)
return nil
}