update doc comment of set_shape
@@ -484,9 +484,10 @@ pub unsafe trait WindowExt: GroupExt {
where
Self: Sized;
/// Set the shape of the window.
- /// Supported images are BMP, RGB and Pixmap.
- /// The window covers non-transparent shape of the image
- /// The image must not be scaled(resized) before hand. The size will be adapted to the window's size
+ /// Supported image formats are BMP, RGB and Pixmap.
+ /// The window covers non-transparent/non-black shape of the image.
+ /// The image must not be scaled(resized) beforehand.
+ /// The size will be adapted to the window's size
fn set_shape<I: ImageExt>(&mut self, image: Option<I>)
where
Self: Sized;
