From 65ded3e62c9b33707b60c2a026aba60fcb06847a Mon Sep 17 00:00:00 2001
From: Julian Orth <ju.orth@gmail.com>
Date: Sun, 6 Oct 2024 21:59:45 +0200
Subject: [PATCH] xdg-toplevel-drag-v1: add set_offset request

This request allows the client to change the offset hint without
unmapping the toplevel. This is useful when the geometry of the toplevel
changes while it is being dragged.

To avoid jank, the hint change is integrated with the commit sequence
that changes the geometry.

Additionally, the client must now perform a commit after attaching a
toplevel to ensure that the offset in the attach request is also in sync
with the geometry of the window.

Signed-off-by: Julian Orth <ju.orth@gmail.com>
---
 .../xdg-toplevel-drag-v1.xml                  | 21 +++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/staging/xdg-toplevel-drag/xdg-toplevel-drag-v1.xml b/staging/xdg-toplevel-drag/xdg-toplevel-drag-v1.xml
index 2fe9645..f1930a6 100644
--- a/staging/xdg-toplevel-drag/xdg-toplevel-drag-v1.xml
+++ b/staging/xdg-toplevel-drag/xdg-toplevel-drag-v1.xml
@@ -24,7 +24,7 @@
     DEALINGS IN THE SOFTWARE.
   </copyright>
 
-  <interface name="xdg_toplevel_drag_manager_v1" version="1">
+  <interface name="xdg_toplevel_drag_manager_v1" version="2">
     <description summary="Move a window during a drag">
       This protocol enhances normal drag and drop with the ability to move a
       window at the same time. This allows having detachable parts of a window
@@ -93,7 +93,7 @@
     </request>
   </interface>
 
-  <interface name="xdg_toplevel_drag_v1" version="1">
+  <interface name="xdg_toplevel_drag_v1" version="2">
     <description summary="Object representing a toplevel move during a drag">
     </description>
 
@@ -129,6 +129,9 @@
         This request can be called multiple times but issuing it while a
         toplevel with an active role is attached raises a toplevel_attached
         error.
+
+        Since version 2, the client must commit the toplevel after this request
+        for the window to start moving.
       </description>
 
       <arg name="toplevel" type="object" interface="xdg_toplevel"/>
@@ -136,6 +139,20 @@
       <arg name="y_offset" type="int" summary="dragged surface y offset"/>
     </request>
 
+    <!-- Version 2 additions -->
+
+    <request name="set_offset" since="2">
+      <description summary="Change the offset hint">
+        This request sets the offset hint for the currently attached surface.
+        The hint is double-buffered state, see wl_surface.commit for details.
+
+        This request has no effect if no surface is attached.
+      </description>
+
+      <arg name="x_offset" type="int" summary="dragged surface x offset"/>
+      <arg name="y_offset" type="int" summary="dragged surface y offset"/>
+    </request>
+
   </interface>
 </protocol>