Compositors need to drive multiple connectors, each with its own vblank timings.
For each device, there's one separate rendering loop per output.
It's not possible to call liftoff_device_apply each time we want to submit a new
frame to one output, because this could touch another's output state, submitting
a new frame there in the process. When the other output will submit a new frame,
it'll get EBUSY (can't submit two frames without waiting for vblank).
Closes: https://github.com/emersion/libliftoff/issues/21
Start from scratch since we may be able to come up with a better allocation
(if the layer made another layer fall back to composition for instance).
Closes: https://github.com/emersion/libliftoff/issues/30
Keep track of the number of layer updates per 60 page-flips.
We could implement a more fine-grained tracking, for instance with a sliding
window. However it's a lot more complex than the current solution and the gains
are not clear. I'd prefer to keep the current solution and experiment with other
solutions once we have a good test-bed.
References: https://github.com/emersion/libliftoff/issues/22
Add a fallback case for finding an eligible CRTC for the
selected connector. The encoder picked may not have been
wired up to that connector by the previous DRM master.
This is a pretty basic benchmark measuring the time spent in
liftoff_display_apply.
The current behaviour tries to reproduce the worst case scenario: layers don't
intersect and one plane is incompatible with all layers.
This test continuously updates a layer's FB for some time, and keeps another
layer static. The continously updated layer should be put in a plane.
The test is disabled for now because priorities aren't implemented yet.
This example demonstrates how incremental layer updates should be applied. It
contains a basic rendering loop. Each layers has a back-buffer and a
front-buffer. The color of one of the layers will change at each frame.
This commit adds basic per-property change tracking.
When only FB_ID has changed, we try to re-use the previous allocation. If that
fails, go on with regular plane allocation.
Closes: https://github.com/emersion/libliftoff/issues/6
Instead of baking plane allocation constraints in output_choose_layers, extract
constraints checked at each step in check_layer_plane_compatible and final
constraints in check_alloc_valid.
Create a special layer that we will use only for composition.
If we manage to put all other layers into planes, we don't need to use it.
Otherwise, blend other layers that didn't make it in a plane.
This lets the library user define a layer where composition will happen. At the
moment there can be at most one composition layer per output, on the primary
plane. It should be possible to remove these restrictions in the future if
desirable.
The composition layer will be put on a plane if and only if composition is
needed.
The compositor needs to know where composited layers will be blended to resolve
zpos conflicts.
Closes: https://github.com/emersion/libliftoff/issues/9
If a plane was previously enabled on another CRTC, we need to set its CRTC_ID to
zero. Otherwise atomic commits fail with:
[drm:drm_atomic_check_only [drm]] [PLANE:31:primary A] CRTC set but no FB
Rename has_composited_layer_on_top to has_composited_layer_over. This is more
consistent with has_allocated_layer_over.
While at it, add a comment to explain why has_allocated_layer_over is named like
so.
Make sure we don't use planes with lower zpos for layers over the previous ones,
unless there is no collision.
This adds the last intersection check.
Closes: https://github.com/emersion/libliftoff/issues/3
And restore the original zpos-4x-disjoint test. Depending on the constraints on
the last two layers, one branch of the layer zpos check or the other is taken.
Fixes: 8617ddfd05 ("Add intersection check for planes under the current one")
