[PATCH weston 2/2] compositor: Move clearing of primary plane damage to the backends

[Pekka Paalanen]

On Thu, 22 Nov 2012 15:57:00 +0200
Ander Conselvan de Oliveira <ander.conselvan.de.oliveira at intel.com>
wrote:

> Backends may move surfaces to different planes, in which case damage is
> generated in the primary plane. This damage is usually passed to the
> renderer, but in some cases the backend may decide to not render
> anything (that's the case when drm compositor scans out a client
> buffer). In that case the damage on the primary plane would be
> discarded, leading to artifacts later.
> 
> This patch makes the backend's responsibility to clear the damage on
> the primary plane, so that unrendered damage is kept for as long as
> necessary.
> ---
> 
> I tested this change with drm, x11 and wayland backends. Android and
> rpi are untested.

Tested on rpi, the same time I was testing my wl_buffer.release
changes. Seems to work ok for what I can see.

Though rpi backend always calls the renderer, even if there was nothing
to render. Maybe it should check in assign_planes, whether any planes
go to the primary plane, and if not, not call the renderer at all.


Thanks,
pq

> The wayland backend has some artifacts, but that happends because it
> is tripple buffering, while the renderer assumes that only two buffers
> are used.
> 
>  src/compositor-android.c  |    4 ++++
>  src/compositor-drm.c      |    3 +++
>  src/compositor-headless.c |    3 +++
>  src/compositor-rpi.c      |    4 ++++
>  src/compositor-wayland.c  |    4 ++++
>  src/compositor-x11.c      |    3 +++
>  src/compositor.c          |    2 --
>  7 files changed, 21 insertions(+), 2 deletions(-)
> 
> diff --git a/src/compositor-android.c b/src/compositor-android.c
> index 2c75e8f..5e27071 100644
> --- a/src/compositor-android.c
> +++ b/src/compositor-android.c
> @@ -92,10 +92,14 @@ android_output_repaint(struct weston_output *base, pixman_region32_t *damage)
>  {
>  	struct android_output *output = to_android_output(base);
>          struct android_compositor *compositor = output->compositor;
> +	struct weston_plane *primary_plane = &compositor->base.primary_plane;
>  	struct wl_event_loop *loop;
>  
>  	compositor->base.renderer->repaint_output(&output->base, damage);
>  
> +	pixman_region32_subtract(&primary_plane->damage,
> +				 &primary_plane->damage, damage);
> +
>  	/* FIXME: does Android have a way to signal page flip done? */
>  	loop = wl_display_get_event_loop(compositor->base.wl_display);
>  	wl_event_loop_add_idle(loop, android_finish_frame, output);
> diff --git a/src/compositor-drm.c b/src/compositor-drm.c
> index 1ecd93c..417b67f 100644
> --- a/src/compositor-drm.c
> +++ b/src/compositor-drm.c
> @@ -357,6 +357,9 @@ drm_output_render(struct drm_output *output, pixman_region32_t *damage)
>  
>  	c->base.renderer->repaint_output(&output->base, damage);
>  
> +	pixman_region32_subtract(&c->base.primary_plane.damage,
> +				 &c->base.primary_plane.damage, damage);
> +
>  	bo = gbm_surface_lock_front_buffer(output->surface);
>  	if (!bo) {
>  		weston_log("failed to lock front buffer: %m\n");
> diff --git a/src/compositor-headless.c b/src/compositor-headless.c
> index 55206b3..d23ee0a 100644
> --- a/src/compositor-headless.c
> +++ b/src/compositor-headless.c
> @@ -66,6 +66,9 @@ headless_output_repaint(struct weston_output *output_base,
>  
>  	ec->renderer->repaint_output(&output->base, damage);
>  
> +	pixman_region32_subtract(&ec->primary_plane.damage,
> +				 &ec->primary_plane.damage, damage);
> +
>  	wl_event_source_timer_update(output->finish_frame_timer, 16);
>  
>  	return;
> diff --git a/src/compositor-rpi.c b/src/compositor-rpi.c
> index 339032a..c75bcda 100644
> --- a/src/compositor-rpi.c
> +++ b/src/compositor-rpi.c
> @@ -914,6 +914,7 @@ rpi_output_repaint(struct weston_output *base, pixman_region32_t *damage)
>  {
>  	struct rpi_output *output = to_rpi_output(base);
>  	struct rpi_compositor *compositor = output->compositor;
> +	struct weston_plane *primary_plane = &compositor->base.primary_plane;
>  	struct rpi_element *element;
>  	DISPMANX_UPDATE_HANDLE_T update;
>  	int layer = 10000;
> @@ -942,6 +943,9 @@ rpi_output_repaint(struct weston_output *base, pixman_region32_t *damage)
>  	 */
>  	compositor->base.renderer->repaint_output(&output->base, damage);
>  
> +	pixman_region32_subtract(&primary_plane->damage,
> +				 &primary_plane->damage, damage);
> +
>  	/* Move the list of elements into the old_element_list. */
>  	wl_list_insert_list(&output->old_element_list, &output->element_list);
>  	wl_list_init(&output->element_list);
> diff --git a/src/compositor-wayland.c b/src/compositor-wayland.c
> index 5376a20..24dccd1 100644
> --- a/src/compositor-wayland.c
> +++ b/src/compositor-wayland.c
> @@ -137,6 +137,10 @@ wayland_output_repaint(struct weston_output *output_base,
>  	wl_callback_add_listener(callback, &frame_listener, output);
>  
>  	ec->renderer->repaint_output(&output->base, damage);
> +
> +	pixman_region32_subtract(&ec->primary_plane.damage,
> +				 &ec->primary_plane.damage, damage);
> +
>  }
>  
>  static void
> diff --git a/src/compositor-x11.c b/src/compositor-x11.c
> index ba18297..b26da09 100644
> --- a/src/compositor-x11.c
> +++ b/src/compositor-x11.c
> @@ -314,6 +314,9 @@ x11_output_repaint(struct weston_output *output_base,
>  
>  	ec->renderer->repaint_output(output_base, damage);
>  
> +	pixman_region32_subtract(&ec->primary_plane.damage,
> +				 &ec->primary_plane.damage, damage);
> +
>  	wl_event_source_timer_update(output->finish_frame_timer, 10);
>  }
>  
> diff --git a/src/compositor.c b/src/compositor.c
> index 2ca48b8..6eb0b8c 100644
> --- a/src/compositor.c
> +++ b/src/compositor.c
> @@ -985,8 +985,6 @@ weston_output_repaint(struct weston_output *output, uint32_t msecs)
>  	pixman_region32_init(&output_damage);
>  	pixman_region32_intersect(&output_damage,
>  				  &ec->primary_plane.damage, &output->region);
> -	pixman_region32_subtract(&ec->primary_plane.damage,
> -				 &ec->primary_plane.damage, &output->region);
>  
>  	if (output->dirty)
>  		weston_output_update_matrix(output);