diff --git a/libweston/backend.h b/libweston/backend.h
index 2374b17bd..e421c660c 100644
--- a/libweston/backend.h
+++ b/libweston/backend.h
@@ -172,8 +172,9 @@ weston_output_transform_coordinate(struct weston_output *output,
 				   double *x, double *y);
 
 void
-weston_output_region_from_global(struct weston_output *output,
-				 pixman_region32_t *region);
+weston_region_global_to_output(pixman_region32_t *dst,
+			       struct weston_output *output,
+			       pixman_region32_t *src);
 
 const struct weston_hdr_metadata_type1 *
 weston_output_get_hdr_metadata_type1(const struct weston_output *output);
diff --git a/libweston/compositor.c b/libweston/compositor.c
index 98eafdf6f..d1e0cbd8a 100644
--- a/libweston/compositor.c
+++ b/libweston/compositor.c
@@ -6202,10 +6202,11 @@ weston_compositor_reflow_outputs(struct weston_compositor *compositor,
 	}
 }
 
-/** Transform a region in-place from global to output coordinates
+/** Transform a region from global to output coordinates
  *
+ * \param dst The region transformed into output coordinates
  * \param output The output that defines the transformation.
- * \param region The region to be transformed in-place.
+ * \param src The region to be transformed, in global coordinates.
  *
  * This takes a region in the global coordinate system, and takes into account
  * output position, transform and scale, and converts the region into output
@@ -6215,10 +6216,11 @@ weston_compositor_reflow_outputs(struct weston_compositor *compositor,
  * \ingroup output
  */
 WL_EXPORT void
-weston_output_region_from_global(struct weston_output *output,
-				 pixman_region32_t *region)
+weston_region_global_to_output(pixman_region32_t *dst,
+			       struct weston_output *output,
+			       pixman_region32_t *src)
 {
-	weston_matrix_transform_region(region, &output->matrix, region);
+	weston_matrix_transform_region(dst, &output->matrix, src);
 }
 
 static void
diff --git a/libweston/pixman-renderer.c b/libweston/pixman-renderer.c
index 62c2cb15b..d6ad4379e 100644
--- a/libweston/pixman-renderer.c
+++ b/libweston/pixman-renderer.c
@@ -414,8 +414,9 @@ draw_view_translated(struct weston_view *view, struct weston_output *output,
 							  repaint_global,
 							  &surface->opaque,
 							  view);
-			weston_output_region_from_global(output,
-							 &repaint_output);
+			weston_region_global_to_output(&repaint_output,
+						       output,
+						       &repaint_output);
 
 			repaint_region(view, output, &repaint_output, NULL,
 				       PIXMAN_OP_SRC);
@@ -426,7 +427,9 @@ draw_view_translated(struct weston_view *view, struct weston_output *output,
 		region_intersect_only_translation(&repaint_output,
 						  repaint_global,
 						  &surface_blend, view);
-		weston_output_region_from_global(output, &repaint_output);
+		weston_region_global_to_output(&repaint_output,
+					       output,
+					       &repaint_output);
 
 		repaint_region(view, output, &repaint_output, NULL,
 			       PIXMAN_OP_OVER);
@@ -462,7 +465,8 @@ draw_view_source_clipped(struct weston_view *view,
 
 	pixman_region32_init(&repaint_output);
 	pixman_region32_copy(&repaint_output, repaint_global);
-	weston_output_region_from_global(output, &repaint_output);
+	weston_region_global_to_output(&repaint_output, output,
+				       &repaint_output);
 
 	repaint_region(view, output, &repaint_output, &buffer_region,
 		       PIXMAN_OP_OVER);
@@ -555,7 +559,7 @@ copy_to_hw_buffer(struct weston_output *output, pixman_region32_t *region)
 	pixman_region32_init(&output_region);
 	pixman_region32_copy(&output_region, region);
 
-	weston_output_region_from_global(output, &output_region);
+	weston_region_global_to_output(&output_region, output, &output_region);
 
 	pixman_image_set_clip_region32 (po->hw_buffer, &output_region);
 	pixman_region32_fini(&output_region);
diff --git a/libweston/renderer-gl/gl-renderer.c b/libweston/renderer-gl/gl-renderer.c
index 3efd805f8..d287ec613 100644
--- a/libweston/renderer-gl/gl-renderer.c
+++ b/libweston/renderer-gl/gl-renderer.c
@@ -1531,7 +1531,8 @@ blit_shadow_to_output(struct weston_output *output,
 	pixman_region32_intersect(&translated_damage, output_damage,
 				  &output->region);
 	/* Convert to output pixel coordinates in-place */
-	weston_output_region_from_global(output, &translated_damage);
+	weston_region_global_to_output(&translated_damage, output,
+				       &translated_damage);
 
 	rects = pixman_region32_rectangles(&translated_damage, &n_rects);
 	for (i = 0; i < n_rects; i++) {