libweston: Add a new helper to check if the view spawns the entire

output

Helpful to determine if the view can go through the scanout or not.

Signed-off-by: Marius Vlad <marius.vlad@collabora.com>

libweston/backend-drm/state-propose.c

@@ -381,7 +381,6 @@ drm_output_prepare_scanout_view(struct drm_output_state *output_state,
 	struct drm_plane *scanout_plane = output->scanout_plane;
 	struct drm_plane_state *state;
 	struct drm_fb *fb;
-	pixman_box32_t *extents;
 
 	assert(!b->sprites_are_broken);
 	assert(b->atomic_modeset);
@@ -389,11 +388,7 @@ drm_output_prepare_scanout_view(struct drm_output_state *output_state,
 
 	/* Check the view spans exactly the output size, calculated in the
 	 * logical co-ordinate space. */
-	extents = pixman_region32_extents(&ev->transform.boundingbox);
-	if (extents->x1 != output->base.x ||
-	    extents->y1 != output->base.y ||
-	    extents->x2 != output->base.x + output->base.width ||
-	    extents->y2 != output->base.y + output->base.height)
+	if (!weston_view_matches_output_entirely(ev, &output->base))
 		return NULL;
 
 	/* If the surface buffer has an in-fence fd, but the plane doesn't

libweston/compositor.c

@@ -1864,6 +1864,29 @@ weston_view_has_valid_buffer(struct weston_view *ev)
 	return ev->surface->buffer_ref.buffer != NULL;
 }
 
+/** Check if the view matches the entire output
+ *
+ * @param ev The view to check.
+ * @param output The output to check against.
+ *
+ * Returns true if the view does indeed matches the entire output.
+ */
+WL_EXPORT bool
+weston_view_matches_output_entirely(struct weston_view *ev,
+				    struct weston_output *output)
+{
+	pixman_box32_t *extents =
+		pixman_region32_extents(&ev->transform.boundingbox);
+
+	if (extents->x1 != output->x ||
+	    extents->y1 != output->y ||
+	    extents->x2 != output->x + output->width ||
+	    extents->y2 != output->y + output->height)
+		return false;
+
+	return true;
+}
+
 /* Check if a surface has a view assigned to it
  *
  * The indicator is set manually when mapping

libweston/libweston-internal.h

@@ -290,6 +290,9 @@ weston_view_is_opaque(struct weston_view *ev, pixman_region32_t *region);
 bool
 weston_view_has_valid_buffer(struct weston_view *ev);
 
+bool
+weston_view_matches_output_entirely(struct weston_view *ev,
+				    struct weston_output *output);
 void
 weston_view_move_to_plane(struct weston_view *view,
 			  struct weston_plane *plane);