Wayland's Weston Can Now Run On DirectFB

[phoronix]

Phoronix: Wayland's Weston Can Now Run On DirectFB

As the latest interesting event in the Wayland world, DirectFB developers have ported Wayland's Weston compositor to run on DirectFB so that any DirectFB platform can now use Weston, including EGL and OpenGL ES support...

http://www.phoronix.com/vr.php?view=MTQ3ODQ

[bison]

What does DirectFB replace in the graphics stack?

I was under the impression that there is nothing between the OS/hardware and Weston other than a device driver for the graphics chip. If Weston can now run on DirectFB, what does Weston run on if DirectFB is not in use? In other words, what does DirectFB replace in the graphics stack?

[Ericg]

I was under the impression that there is nothing between the OS/hardware and Weston other than a device driver for the graphics chip. If Weston can now run on DirectFB, what does Weston run on if DirectFB is not in use? In other words, what does DirectFB replace in the graphics stack?

I could be wrong, but I'm thinking it inserts itself between System Compositor and the kernel

[pq__]

I was under the impression that there is nothing between the OS/hardware and Weston other than a device driver for the graphics chip. If Weston can now run on DirectFB, what does Weston run on if DirectFB is not in use?

You can make Weston run on quite many things if you want to, with varying degree of performance and features. Weston runs on X11, too. Native Weston, if we can use that term, runs on the kernel DRM & KMS interfaces and Mesa EGL and GL drivers. Weston can run even on fbdev (not accelerated), so as long as there is a way to present the output, you could make Weston run on it at least. Also input needs to come from somewhere.

[bison]

I could be wrong, but I'm thinking it inserts itself between System Compositor and the kernel

Thanks for the diagram. It looks like DirectFB is an addition to the normal Wayland graphics stack, which still leaves me wondering what it's there for.

[bison]

You can make Weston run on quite many things if you want to, with varying degree of performance and features. Weston runs on X11, too. Native Weston, if we can use that term, runs on the kernel DRM & KMS interfaces and Mesa EGL and GL drivers. Weston can run even on fbdev (not accelerated), so as long as there is a way to present the output, you could make Weston run on it at least. Also input needs to come from somewhere.

Thanks for the explanation. So... what would be the advantage of running Weston (or some other Wayland compositor) on DirectFB instead of directly on the kernel and Mesa drivers?

[Ancurio]

Thanks for the explanation. So... what would be the advantage of running Weston (or some other Wayland compositor) on DirectFB instead of directly on the kernel and Mesa drivers?

Maybe being able to run it on platforms where there's neither KMS nor DRM? (mobile for example)

[smitty3268]

Thanks for the explanation. So... what would be the advantage of running Weston (or some other Wayland compositor) on DirectFB instead of directly on the kernel and Mesa drivers?

My understanding is that it competes with the DRM/KMS kernel drivers. That DirectFB is quite popular with certain embedded devices, while DRM/KMS was more driven from the desktop side. And that the 2 camps aren't very friendly with one another, with each kind of questioning the purpose of having a 2nd option since they think theirs is sufficient for everything.

[Ericg]

My understanding is that it competes with the DRM/KMS kernel drivers. That DirectFB is quite popular with certain embedded devices, while DRM/KMS was more driven from the desktop side. And that the 2 camps aren't very friendly with one another, with each kind of questioning the purpose of having a 2nd option since they think theirs is sufficient for everything.

If you read the Arch wiki page for DirectFB, one of the reasons it wins out on the mobile side is it mainly concerns itself with single application displaying. Now, DirectFB 3 is supposed to TRY to fix that, but its not out yet. So if you want multiple apps on screen at once...which most of us do... DirectFB ain't what ya looking for.