Add a mechanism to delay unmapping of surfaces

When a client attachs a NULL buffer on a surface we may want to hang on
to the old buffer for a bit, e.g. to do a hide animation.
Add the QWaylandUnmapLock class to keep a surface mapped after an attach(0)
request.

Change-Id: I5d5be0b36410a76a58d2b68c1b2ac5e3b875a801
Reviewed-by: Robin Burchell <robin.burchell@viroteck.net>

1 files changed, 2 insertions, 1 deletions

diff --git a/src/compositor/compositor_api/qwaylandbufferref.h b/src/compositor/compositor_api/qwaylandbufferref.h
index 213474fab..103a1b388 100644
--- a/src/compositor/compositor_api/qwaylandbufferref.h
+++ b/src/compositor/compositor_api/qwaylandbufferref.h
@@ -65,7 +65,8 @@ public:
 #ifdef QT_COMPOSITOR_WAYLAND_GL
     /**
      * There must be a GL context bound when calling this function.
-     * It is responsibility of the caller to call destroyTexture() later.
+     * The texture will be automatically destroyed when the last QWaylandBufferRef
+     * referring to the same underlying buffer will be destroyed or reset.
      */
     GLuint createTexture();
     void destroyTexture();