DRM page-flip with damage for weston

[Daniel Stone]

Hi Deepak,

On Wed, 25 Jul 2018 at 18:26, Deepak Singh Rawat <drawat at vmware.com> wrote:
> > The damage region received during output repaint is in Weston's global
> > co-ordinate space. To shift to CRTC co-ordinates, you need to
> > translate the damage region by (-output->x, -output->y). When we are
> > using the renderer, there is no scaling, so CRTC co-ordinates and
> > framebuffer co-ordinates are guaranteed to be equal. This only
> > accounts for the primary plane; damage to views on other planes is
> > considered separately.
> >
> > Also, if you are not already working from git master, I recommend you
> > do so, as the DRM backend has changed hugely since 4.0.0.
>
> Thanks Daniel for help and it the change suggested by you are working with
> my drm code. Another question regarding Weston, does each output in
> Weston create separate scan-out framebuffer always ?

No problem - it does always create a separate scanout buffer for
renderer (GL/etc) buffers. For user buffers which are directly scanned
out (e.g. fullscreen windows), the user may have specified a viewport
scale/crop which requires translation, but I don't think this should
have an effect if the damage region you are after has to be in CRTC
co-ords.

Cheers,
Daniel