Hi Shawn, On Mon, 16 Oct 2023 at 06:23, Shawn Sung (宋孝謙) <Shawn.Sung@xxxxxxxxxxxx> wrote: > On Fri, 2023-10-13 at 17:26 +0100, Daniel Stone wrote: > > If I understand the driver correctly, padding is automatically > > applied > > to compensate for unaligned dimensions. The first/last rows/columns > > of > > the overlay area will be filled with a specified colour (black?) to > > preserve the area. This is unfortunately not OK to do transparently. > > Userspace must be aware of this policy decision and specifically > > request it. If not, the atomic request check should fail and tell > > userspace that the requested configuration is not possible to > > achieve. > > Yes, Padding works as you described, users can assign background colors > for the filled area in 10bit RGB format, however, the rows and columns > that are filled by Padding will be cropped by the hardware components > after it to avoid situations as you mentioned, so users should not > notice any difference. Thanks for the explanation, I hadn't realised that the added padding later gets cropped. Cheers, Daniel