protocol: Introduce pointer_lock interfacepointer-lock-2

The pointer_lock interface is modelled after the HTML5 pointer lock
extension:

  https://dvcs.w3.org/hg/pointerlock/raw-file/default/index.html

The extension allows a wayland client to lock the pointer while a surface
is active.  While the pointer is locked, the client receives relative
motion events and the pointer position isn't updated.

1 files changed, 36 insertions, 1 deletions

diff --git a/protocol/wayland.xml b/protocol/wayland.xml
index 61fde84..a5e4666 100644
--- a/protocol/wayland.xml
+++ b/protocol/wayland.xml
@@ -1236,7 +1236,7 @@
     </request>
    </interface>
 
-  <interface name="wl_seat" version="3">
+  <interface name="wl_seat" version="4">
     <description summary="group of input devices">
       A seat is a group of keyboards, pointer and touch devices. This
       object is published as a global during start up, or when such a
@@ -1252,6 +1252,7 @@
       <entry name="pointer" value="1" summary="The seat has pointer devices"/>
       <entry name="keyboard" value="2" summary="The seat has one or more keyboards"/>
       <entry name="touch" value="4" summary="The seat has touch devices"/>
+      <entry name="pointer_lock" value="8" summary="lock pointer"/>
     </enum>
 
     <event name="capabilities">
@@ -1307,6 +1308,40 @@
       <arg name="name" type="string"/>
     </event>
 
+
+    <request name="lock_pointer" since="4">
+      <description summary="return pointer object">
+	The lock_pointer request lets the client disable pointer
+	motion and request relative motion events.
+
+	This request initializes the pointer lock and activates it in
+	case the surface is active.  If the surface isn't active when
+	the server receives the request, the compositor will activate
+	the pointer_lock when the surface is eventually activated.
+
+	The lock_pointer request will create a new wl_pointer object.
+	When the pointer_lock is activated, the regular wl_seat
+	pointer send out a leave event and the pointer_lock wl_pointer
+	object will receive an enter event.  The enter event will
+	indicate the position of the pointer at the time of
+	activation.  While the pointer lock is active, the wl_pointer
+	object will send out motion events, but the coordinates
+	correspond to relative pointer motion.
+
+	The compositor can break the pointer_lock at any time, for
+	example when switching to a different application (eg,
+	alt-tab), if a notification pops up or when the screensaver
+	starts.  When this happens the pointer lock wl_pointer will
+	send a leave event.  When or if the server activates the
+	surface again, the client will receive an enter event again.
+
+	The client can break the pointer lock at any time by releasing
+	the pointer lock wl_pointer using the wl_pointer.release request.
+      </description>
+      <arg name="id" type="new_id" interface="wl_pointer"/>
+      <arg name="surface" type="object" interface="wl_surface"/>
+    </request>
+
   </interface>
 
   <interface name="wl_pointer" version="3">