drm/state-propose: Remove unused planes_region member

We used to use planes_region for the output regions which were being
displayed on hardware planes; before we grew zpos awareness, we couldn't
have any planes overlapping with each other, since the ordering would be
undefined.

Since the zpos awareness though, this region is unused, so we can just
remove it.

Signed-off-by: Daniel Stone <daniels@collabora.com>

libweston/backend-drm/state-propose.c

@@ -769,7 +769,7 @@ drm_output_propose_state(struct weston_output *output_base,
 	struct drm_plane_state *scanout_state = NULL;
 	struct weston_view *ev;
 
-	pixman_region32_t surface_overlap, renderer_region, planes_region;
+	pixman_region32_t surface_overlap, renderer_region;
 	pixman_region32_t occluded_region;
 
 	bool renderer_ok = (mode != DRM_OUTPUT_PROPOSE_STATE_PLANES_ONLY);
@@ -830,8 +830,6 @@ drm_output_propose_state(struct weston_output *output_base,
 
 	/* - renderer_region contains the total region which which will be
 	 *   covered by the renderer
-	 * - planes_region contains the total region which has been covered by
-	 *   hardware planes
 	 * - occluded_region contains the total region which which will be
 	 *   covered by the renderer and hardware planes, where the view's
 	 *   visible-and-opaque region is added in both cases (the view's
@@ -840,7 +838,6 @@ drm_output_propose_state(struct weston_output *output_base,
 	 *   situation where occluded_region covers entire output's region.
 	 */
 	pixman_region32_init(&renderer_region);
-	pixman_region32_init(&planes_region);
 	pixman_region32_init(&occluded_region);
 
 	wl_list_for_each(ev, &output_base->compositor->view_list, link) {
@@ -940,10 +937,6 @@ drm_output_propose_state(struct weston_output *output_base,
 			 * be added to the renderer region nor the occluded
 			 * region. */
 			if (ps->plane->type != WDRM_PLANE_TYPE_CURSOR) {
-				pixman_region32_union(&planes_region,
-						      &planes_region,
-						      &clipped_view);
-
 				if (!weston_view_is_opaque(ev, &clipped_view))
 					pixman_region32_intersect(&clipped_view,
 								  &clipped_view,
@@ -991,7 +984,6 @@ drm_output_propose_state(struct weston_output *output_base,
 	}
 
 	pixman_region32_fini(&renderer_region);
-	pixman_region32_fini(&planes_region);
 	pixman_region32_fini(&occluded_region);
 
 	/* In renderer-only mode, we can't test the state as we don't have a