Add wl_surface.enter and wl_surface.leave events

These events let us track when a surface enters or leaves the scanout region of
an output. This way if a surface moves to another output and that output is on
a different card, we can suggest the toolkit reallocate its buffers
appropriately.

Signed-off-by: Casey Dahlin <cdahlin@redhat.com>

diff --git a/protocol/wayland.xml b/protocol/wayland.xml
index f50ca3f..a11cbbe 100644 (file)
--- a/protocol/wayland.xml
+++ b/protocol/wayland.xml
@@ -660,6 +660,24 @@
 
       <arg name="region" type="object" interface="wl_region"/>
     </request>
+
+    <event name="enter">
+      <description summary="surface enters an output">
+        This is emitted whenever a surface's creation, movement, or resizing
+        results in some part of it being within the scanout region of an
+        output.
+      </description>
+      <arg name="output" type="object" interface="wl_output"/>
+    </event>
+
+    <event name="leave">
+      <description summary="surface leaves an output">
+        This is emitted whenever a surface's creation, movement, or resizing
+        results in it no longer having any part of it within the scanout region
+        of an output.
+      </description>
+      <arg name="output" type="object" interface="wl_output"/>
+    </event>
   </interface>
 
   <interface name="wl_input_device" version="1">