gtk-demo: Fix drawing of gestures demo feedback on CSD windows

It was wiping the translation initially applied to the cairo_t, so
pick that up first before applying our own matrix changes.

1 files changed, 4 insertions, 3 deletions

diff --git a/demos/gtk-demo/gestures.c b/demos/gtk-demo/gestures.c
index b5a29583c2..f8e475817d 100644
--- a/demos/gtk-demo/gestures.c
+++ b/demos/gtk-demo/gestures.c
@@ -86,9 +86,10 @@ drawing_area_draw (GtkWidget *widget,
       cairo_matrix_t matrix;
       gdouble angle, scale;
 
-      cairo_matrix_init_translate (&matrix,
-                                   allocation.width / 2,
-                                   allocation.height / 2);
+      cairo_get_matrix (cr, &matrix);
+      cairo_matrix_translate (&matrix,
+                              allocation.width / 2,
+                              allocation.height / 2);
 
       cairo_save (cr);