From c002321cd6f2468ed5a1e0292da001c9e13cedcb Mon Sep 17 00:00:00 2001
From: Derek Foreman <derekf@osg.samsung.com>
Date: Tue, 24 Mar 2015 11:36:13 -0500
Subject: [PATCH] compositor: Create the inverse of the output matrix

Signed-off-by: Derek Foreman <derekf@osg.samsung.com>
Reviewed-by: Bryce Harrington <b.harrington@samsung.com>
Reviewed-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
---
 src/compositor.c | 2 ++
 src/compositor.h | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/src/compositor.c b/src/compositor.c
index 47da8183..623dff31 100644
--- a/src/compositor.c
+++ b/src/compositor.c
@@ -4003,6 +4003,8 @@ weston_output_update_matrix(struct weston_output *output)
 				    output->current_scale, 1);
 
 	output->dirty = 0;
+
+	weston_matrix_invert(&output->inverse_matrix, &output->matrix);
 }
 
 static void
diff --git a/src/compositor.h b/src/compositor.h
index 24ed4fc0..be323123 100644
--- a/src/compositor.h
+++ b/src/compositor.h
@@ -185,6 +185,8 @@ struct weston_output {
 
 	/** From global to output buffer coordinates. */
 	struct weston_matrix matrix;
+	/** From output buffer to global coordinates. */
+	struct weston_matrix inverse_matrix;
 
 	struct wl_list animation_list;
 	int32_t x, y, width, height;