>On Tue, Aug 10, 2021 at 05:57:31PM +0100, John Cox wrote: >> Hi all >> >> I am on a Raspberry Pi, I want to display fullscreen video and have a >> couple of overlay planes to display controls / subtitles etc. The h/w >> can certainly do this. I need to be able to do this from a starting >> point where X is running. >> >> I can successfully find X's output & crtc and grab that using >> xcb_randr_create_lease and use that handle to display video. So far so >> good. But I also want to have overlay planes for subtitles etc. The >> handle I've got from the lease only seems to have a PRIMARY & a CURSOR >> plane attached so I can't get anything there. > >I think X just gives you a legacy lease for the crtc, and the kernel >automatically adds the primary plane and cursor plane (if they exist) to >that lease. Unless X is patched to enable plane support and add those all >explicitly to the lease I don't think there's a way for that. Bother. So near and yet so far. Thanks for the info. >For wayland this is still in the works, so might be good if you check >there that your use-case is properly supported. Protocol MR is here: > >https://gitlab.freedesktop.org/wayland/wayland-protocols/-/merge_requests/67 In overall protocol terms that doesn't seem so different from what X does and I am far too inexperienced in Wayland / DRM to understand the subtleties. That MR seems to be done so is probably an inappropriate place to ask - where would you recommend as an appropriate forum? Many thanks John Cox >> How should I be going about getting some more planes to use for >> overlays? Pointers to documentation / examples gratefully received - so >> far my google-foo has failed to find anything that works. >> >> I'm sorry if this is the wrong place to ask, but if there is a better >> place please say and I'll go there. >> >> Many thanks >> >> John Cox
