On Mon, Mar 18, 2013 at 4:17 PM, Bill Spitzak <spit...@gmail.com> wrote: > Jason Ekstrand wrote: > >>> For sub-pixel rendering the solution i have been thinking for a while >>> but still haven't had time to prototype on weston, is to have weston >>> send the transformation matrix to the client have the client render in >>> screen coordinate space and when commiting its surface the client >>> would also tell which transformation matrix it did use. > > >> Yes, adding some support for that might be a good idea. However, this >> becomes a bit of an issue because the surface might not be rectangular >> anymore or it might be rotated. How do you recommend getting around >> this? > > > If the client ignores the transform sent from the compositor, then it will > draw a rectangular image that fills the buffer it allocated. > > If the client uses the transform sent from the compositor then it will > realize that it's rectangular image when transformed has a larger bounding > box and will allocate a buffer of that size, clear the unused area, and draw > the rotated rectangle. > > The client is going to have to be able to tell the compositor that the > buffer image represents a surface of a given rectangular size with a given > transform (the compositor cannot get the rectangle back from the buffer size > and transform as there are many possible rectangles at the given angle that > fill a given bounding box). This means this information must be separated > from the buffer size. > > This will also allow a client to specify a subrectangle of the buffer as a > surface, and (more importantly imho) specify that the buffer does not fill > the surface, for instances where it knows the decorations are clipped off. >
Yes this is the idea i had, the client render in screen space and send to the server a possible bigger buffer than what its window need. Client send the screen space buffer size (wdith & height) but also the untransformed size (width and height) and the transformation matrix that was use. You also need a rounding convention which in this case should be ceil All other information such as opaque region will be given untransformed. Cheers, Jerome _______________________________________________ wayland-devel mailing list wayland-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/wayland-devel