From a8f12e7afdb35ebda581cee6a32b295cb6e643ec Mon Sep 17 00:00:00 2001

From: Carlos Garnacho <carlosg@gnome.org>

Date: Fri, 13 Dec 2019 14:22:12 +0100

Subject: [PATCH] backends/x11: Observe multiple pad mode switch buttons in a

 group

Some tablets like the Cintiq 24HDT have several mode switch buttons

per group. Those are meant to jump straight to a given mode, however

we just handle cycling across modes (as most other tablets have a

single mode switch button per group).

So spice up the mode switch handling so we handle multiple mode

switch buttons, assigning each of them a mode. If the device only

has one mode switch button, we do the old-fashioned cycling.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/970

---

 .../clutter/x11/clutter-input-device-xi2.c    | 71 ++++++++++++++++---

 1 file changed, 60 insertions(+), 11 deletions(-)

diff --git a/clutter/clutter/x11/clutter-input-device-xi2.c b/clutter/clutter/x11/clutter-input-device-xi2.c

index 1254aca3a..c33adffc2 100644

--- a/clutter/clutter/x11/clutter-input-device-xi2.c

+++ b/clutter/clutter/x11/clutter-input-device-xi2.c

@@ -318,6 +318,57 @@ clutter_input_device_xi2_get_pad_group_mode (ClutterInputDevice *device,

   return g_array_index (device_xi2->group_modes, guint, group);

 }

+static gboolean

+pad_switch_mode (ClutterInputDevice *device,

+                 uint32_t            button,

+                 uint32_t            group,

+                 uint32_t           *mode)

+{

+  ClutterInputDeviceXI2 *device_x11 = CLUTTER_INPUT_DEVICE_XI2 (device);

+  uint32_t n_buttons, n_modes, button_group, next_mode, i;

+  GList *switch_buttons = NULL;

+

+  n_buttons = libwacom_get_num_buttons (device_x11->wacom_device);

+

+  for (i = 0; i < n_buttons; i++)

+    {

+      button_group = clutter_input_device_xi2_get_button_group (device, i);

+      if (button_group == group)

+        switch_buttons = g_list_prepend (switch_buttons, GINT_TO_POINTER (i));

+    }

+

+  switch_buttons = g_list_reverse (switch_buttons);

+  n_modes = clutter_input_device_get_group_n_modes (device, group);

+

+  if (g_list_length (switch_buttons) > 1)

+    {

+      /* If there's multiple switch buttons, we don't toggle but assign a mode

+       * to each of those buttons.

+       */

+      next_mode = g_list_index (switch_buttons, GINT_TO_POINTER (button));

+    }

+  else if (switch_buttons)

+    {

+      uint32_t cur_mode;

+

+      /* If there is a single button, have it toggle across modes */

+      cur_mode = g_array_index (device_x11->group_modes, uint32_t, group);

+      next_mode = (cur_mode + 1) % n_modes;

+    }

+  else

+    {

+      return FALSE;

+    }

+

+  g_list_free (switch_buttons);

+

+  if (next_mode < 0 || next_mode > n_modes)

+    return FALSE;

+

+  *mode = next_mode;

+  return TRUE;

+}

+

 void

 clutter_input_device_xi2_update_pad_state (ClutterInputDevice *device,

                                            guint               button,

@@ -330,23 +381,21 @@ clutter_input_device_xi2_update_pad_state (ClutterInputDevice *device,

   gboolean is_mode_switch = FALSE;

   button_group = clutter_input_device_xi2_get_button_group (device, button);

-  is_mode_switch = button_group >= 0;

-  /* Assign all non-mode-switch buttons to group 0 so far */

-  button_group = MAX (0, button_group);

-

-  if (button_group >= device_xi2->group_modes->len)

-    return;

+  if (button_group < 0 || button_group >= device_xi2->group_modes->len)

+    {

+      *group = *mode = 0;

+      return;

+    }

   group_mode = &g_array_index (device_xi2->group_modes, guint, button_group);

-  if (is_mode_switch && state)

+  if (state)

     {

-      guint next, n_modes;

+      uint32_t next_mode;

-      n_modes = clutter_input_device_get_group_n_modes (device, button_group);

-      next = (*group_mode + 1) % n_modes;

-      *group_mode = next;

+      if (pad_switch_mode (device, button, button_group, &next_mode))

+        *group_mode = next_mode;

     }

   if (group)

-- 

2.23.0