func ScreenRect() (image.Rectangle, error) {
c, err := xgb.NewConn()
if err != nil {
return image.Rectangle{}, err
}
defer c.Close()
screen := xproto.Setup(c).DefaultScreen(c)
x := screen.WidthInPixels
y := screen.HeightInPixels
return image.Rect(0, 0, int(x), int(y)), nil
}
func CaptureRect(rect image.Rectangle) (*image.RGBA, error) {
c, err := xgb.NewConn()
if err != nil {
return nil, err
}
defer c.Close()
screen := xproto.Setup(c).DefaultScreen(c)
x, y := rect.Dx(), rect.Dy()
xImg, err := xproto.GetImage(c, xproto.ImageFormatZPixmap, xproto.Drawable(screen.Root), int16(rect.Min.X), int16(rect.Min.Y), uint16(x), uint16(y), 0xffffffff).Reply()
if err != nil {
return nil, err
}
data := xImg.Data
for i := 0; i < len(data); i += 4 {
data[i], data[i+2], data[i+3] = data[i+2], data[i], 255
}
img := &image.RGBA{data, 4 * x, image.Rect(0, 0, x, y)}
return img, nil
}