Implement relative pointer mode on Wayland

yasl_surface_set_pointer_mode(YASL_POINTER_RELATIVE) now takes a
persistent zwp_locked_pointer_v1 on the surface and hides its cursor.
While the compositor keeps the lock engaged, zwp_relative_pointer_v1
motion is pushed as POINTER_MOTION with pos frozen and delta in device
pixels. When the lock disengages, as on focus loss, motion is absolute
again with a delta derived by the input queue.

The lock follows the pointer's seat: it moves to another seat when its
seat loses the pointer, and is released on NORMAL and on surface
destruction. Compositors without both protocols return false.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/src/platform/wayland/surface.c b/src/platform/wayland/surface.c
index ad3a24c..b17d203 100644
--- a/src/platform/wayland/surface.c
+++ b/src/platform/wayland/surface.c
@@ -200,6 +200,8 @@ static void display_free(struct wayland_display *c)
     if (c->primary_selection_mgr) zwp_primary_selection_device_manager_v1_destroy(c->primary_selection_mgr);
     if (c->data_manager) wl_data_device_manager_destroy(c->data_manager);
     if (c->cursor_shape_mgr) wp_cursor_shape_manager_v1_destroy(c->cursor_shape_mgr);
+    if (c->relative_pointer_mgr) zwp_relative_pointer_manager_v1_destroy(c->relative_pointer_mgr);
+    if (c->pointer_constraints) zwp_pointer_constraints_v1_destroy(c->pointer_constraints);
     if (c->cursor_theme) wl_cursor_theme_destroy(c->cursor_theme);
     if (c->tablet_mgr) zwp_tablet_manager_v2_destroy(c->tablet_mgr);
     if (c->text_input_mgr) zwp_text_input_manager_v3_destroy(c->text_input_mgr);
@@ -399,6 +401,7 @@ void wayland_surface_destroy(struct wayland_surface *w)
     if (!w || w->destroyed) return;
     for (struct wayland_surface *o = w->conn ? w->conn->surfaces : NULL; o; o = o->conn_next)
         assert(o->parent != w && "destroy a popup before its parent");
+    surface_unlock_pointer(w);
     input_queue_clear(&w->input);
     free(w->ime_preedit);
     free(w->ime_commit);