We don't need to worry about the black rect optimization here (that
always assumes that there will be a black background) because the
background is culled based on the render list. That means if a black rect
is removed, the visibility will reach all the way to the bottom forcing
the renderer to clear the area not breaking the assumption.
If culling is not enabled, there is no longer any guarantee that the
elements behind the rect won't be rendered. We must render the black rect
in all circumstances to cover up anything rendered.
This fixes the WLR_SCENE_DISABLE_VISIBILTY option.
This has a few benefits one of them crucial for proper operation:
- The primary output will be based on the largest area that is actually
visible to the user. Presentation and frame done events are based on
this state. This is important to do since we cull frame done events.
If we happen to be in a situation where a surface sits mostly on output
A and some on output B but is completely obstructed by for instance a
fullscreen surface on output A we will erroneously send frame_done
events based on output A. If we base things as they are in reality
(visibility) the primary output will instead be output B and things will
work properly.
- The primary output will be NULL if the surface is completely hidden.
Due to quirks with wayland, on a surface commit, frame done events are
required to be sent. Therefore, a new frame will be submitted for rendering
on the primary output. We can improve adaptive sync on completely hidden
but enabled surfaces if we null out the primary output in this state.
- The client will be more likely to choose better metadata to use
for rendering to an output's optimal rendering characteristics.
We can also get rid of the intersection checks in the rendering functions
because we are guaranteed to already be in the node do to the prior
intersection checking of the node visibility.
Simplify damage handling by using our cached visibility state.
Damaging can happen in one step because since we can use the old visibility
state which represent what portions of the screen the scene node was. This
way we can damage everything in one step after the fact.
Will query the scene for all nodes that appear in the given wlr_box.
The nodes will be sent to the iterator from closest to farthest from the
eye.
Refactor wlr_scene_node_at to use this new function.
This will display red translucent rectangles on the screen regions that
have been damaged. These rectangles will fade out over the span of 250
msecs. If the area is damaged again while the region is fading out,
the timer is reset.
Let's also disable direct scan out when this option is enabled, or else
we won't be able to render the highlight damage regions.
This function sidesteps damage tracking and output awareness on
buffers/surfaces. This function isn't a great fit for the API.
Let's also inline the function and simplify it.