[mutter/wip/carlosg/fix-pad-osds-position: 225/225] backends: Check both input settings and mapper for tablet monitors

[Carlos Garnacho <carlosg src gnome org>]

commit 09b30d904b4a4380674f1e8008510e337da82333
Author: Carlos Garnacho <carlosg gnome org>
Date:   Fri Dec 13 15:26:05 2019 +0100

    backends: Check both input settings and mapper for tablet monitors
    
    The upper layers (OSDs basically) want to know the monitor that a
    tablet is currently assigned to, not the monitor just as configured
    through settings.
    
    This broke proper OSD positioning for display-attached tablets since
    commit 87858a4e01d9, as the MetaInputMapper kicks in precisely when
    there is no configured monitor for the given device.
    
    Consulting both about the assigned output will make OSDs pop up
    again in the right place.
    
    https://gitlab.gnome.org/GNOME/mutter/merge_requests/971

 src/backends/meta-input-mapper-private.h |  3 ++
 src/backends/meta-input-mapper.c         | 26 +++++++++++++++
 src/backends/meta-input-settings.c       | 56 ++++++++++++++++++++++++++++++--
 3 files changed, 83 insertions(+), 2 deletions(-)
---
diff --git a/src/backends/meta-input-mapper-private.h b/src/backends/meta-input-mapper-private.h
index 34314577f..cdfdccde9 100644
--- a/src/backends/meta-input-mapper-private.h
+++ b/src/backends/meta-input-mapper-private.h
@@ -42,5 +42,8 @@ ClutterInputDevice *
 meta_input_mapper_get_logical_monitor_device (MetaInputMapper        *mapper,
                                               MetaLogicalMonitor     *logical_monitor,
                                               ClutterInputDeviceType  device_type);
+MetaLogicalMonitor *
+meta_input_mapper_get_device_logical_monitor (MetaInputMapper *mapper,
+                                              ClutterInputDevice *device);
 
 #endif /* META_INPUT_MAPPER_H */
diff --git a/src/backends/meta-input-mapper.c b/src/backends/meta-input-mapper.c
index 0e5a5f5c3..a241af3f5 100644
--- a/src/backends/meta-input-mapper.c
+++ b/src/backends/meta-input-mapper.c
@@ -675,3 +675,29 @@ meta_input_mapper_get_logical_monitor_device (MetaInputMapper        *mapper,
 
   return NULL;
 }
+
+MetaLogicalMonitor *
+meta_input_mapper_get_device_logical_monitor (MetaInputMapper    *mapper,
+                                              ClutterInputDevice *device)
+{
+  MetaMapperOutputInfo *output;
+  MetaLogicalMonitor *logical_monitor;
+  GHashTableIter iter;
+  GList *l;
+
+  g_hash_table_iter_init (&iter, mapper->output_devices);
+
+  while (g_hash_table_iter_next (&iter, (gpointer *) &logical_monitor,
+                                 (gpointer *) &output))
+    {
+      for (l = output->input_devices; l; l = l->next)
+        {
+          MetaMapperInputInfo *input = l->data;
+
+          if (input->device == device)
+            return logical_monitor;
+        }
+    }
+
+  return NULL;
+}
diff --git a/src/backends/meta-input-settings.c b/src/backends/meta-input-settings.c
index 3bee36d41..71a79d109 100644
--- a/src/backends/meta-input-settings.c
+++ b/src/backends/meta-input-settings.c
@@ -2086,6 +2086,44 @@ meta_input_settings_get_tablet_settings (MetaInputSettings  *settings,
   return info ? g_object_ref (info->settings) : NULL;
 }
 
+static ClutterInputDevice *
+find_grouped_pen (MetaInputSettings  *settings,
+                  ClutterInputDevice *device)
+{
+  MetaInputSettingsPrivate *priv;
+  GList *l, *devices;
+  ClutterInputDeviceType device_type;
+  ClutterInputDevice *pen = NULL;
+
+  device_type = clutter_input_device_get_device_type (device);
+
+  if (device_type == CLUTTER_TABLET_DEVICE ||
+      device_type == CLUTTER_PEN_DEVICE)
+    return device;
+
+  priv = meta_input_settings_get_instance_private (settings);
+  devices = clutter_seat_list_devices (priv->seat);
+
+  for (l = devices; l; l = l->next)
+    {
+      ClutterInputDevice *other_device = l->data;
+
+      device_type = clutter_input_device_get_device_type (other_device);
+
+      if ((device_type == CLUTTER_TABLET_DEVICE ||
+           device_type == CLUTTER_PEN_DEVICE) &&
+          clutter_input_device_is_grouped (device, other_device))
+        {
+          pen = l->data;
+          break;
+        }
+    }
+
+  g_list_free (devices);
+
+  return pen;
+}
+
 MetaLogicalMonitor *
 meta_input_settings_get_tablet_logical_monitor (MetaInputSettings  *settings,
                                                 ClutterInputDevice *device)
@@ -2097,13 +2135,27 @@ meta_input_settings_get_tablet_logical_monitor (MetaInputSettings  *settings,
   g_return_val_if_fail (META_IS_INPUT_SETTINGS (settings), NULL);
   g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device), NULL);
 
+  if (clutter_input_device_get_device_type (device) == CLUTTER_PAD_DEVICE)
+    {
+      device = find_grouped_pen (settings, device);
+      if (!device)
+        return NULL;
+    }
+
   priv = meta_input_settings_get_instance_private (settings);
   info = g_hash_table_lookup (priv->mappable_devices, device);
   if (!info)
     return NULL;
 
-  meta_input_settings_find_monitor (settings, info->settings, device,
-                                    NULL, &logical_monitor);
+  logical_monitor =
+    meta_input_mapper_get_device_logical_monitor (priv->input_mapper, device);
+
+  if (!logical_monitor)
+    {
+      meta_input_settings_find_monitor (settings, info->settings, device,
+                                        NULL, &logical_monitor);
+    }
+
   return logical_monitor;
 }