1 files changed, 14 insertions, 1 deletions
diff --git a/include/wlr/types/wlr_output.h b/include/wlr/types/wlr_output.h
index a974a154..8e4f5446 100644
--- a/include/wlr/types/wlr_output.h
+++ b/include/wlr/types/wlr_output.h
@@ -118,6 +118,19 @@ bool wlr_output_cursor_move(struct wlr_output_cursor *cursor,
 	double x, double y);
 void wlr_output_cursor_destroy(struct wlr_output_cursor *cursor);
 
-enum wl_output_transform wlr_output_transform_invert(enum wl_output_transform);
+
+/**
+ * Returns the transform that, when composed with `tr`, gives
+ * `WL_OUTPUT_TRANSFORM_NORMAL`.
+ */
+enum wl_output_transform wlr_output_transform_invert(
+	enum wl_output_transform tr);
+
+/**
+ * Returns a transform that, when applied, has the same effect as applying
+ * sequentially `tr_a` and `tr_b`.
+ */
+enum wl_output_transform wlr_output_transform_compose(
+	enum wl_output_transform tr_a, enum wl_output_transform tr_b);
 
 #endif