Overlay Mouse: Alt 2-Touch Input option (libretro#18580)

neil4 · web-flow · commit 8c1afaac4d72 · 2026-01-06T16:18:01.000+01:00
Use second touch as a mouse button while controlling the cursor.
diff --git a/config.def.h b/config.def.h
@@ -640,6 +640,7 @@
 #define DEFAULT_INPUT_OVERLAY_MOUSE_DTAP_TO_DRAG false
 #define DEFAULT_INPUT_OVERLAY_MOUSE_DTAP_MSEC 200
 #define DEFAULT_INPUT_OVERLAY_MOUSE_SWIPE_THRESHOLD 1.0f
+#define DEFAULT_INPUT_OVERLAY_MOUSE_ALT_TWO_TOUCH_INPUT OVERLAY_MOUSE_BTN_NONE
 
 #ifdef UDEV_TOUCH_SUPPORT
 #define DEFAULT_INPUT_TOUCH_VMOUSE_POINTER true
diff --git a/configuration.c b/configuration.c
@@ -2669,6 +2669,7 @@ static struct config_uint_setting *populate_settings_uint(
    SETTING_UINT("input_overlay_lightgun_four_touch_input",  &settings->uints.input_overlay_lightgun_four_touch_input, true, DEFAULT_INPUT_OVERLAY_LIGHTGUN_MULTI_TOUCH_INPUT, false);
    SETTING_UINT("input_overlay_mouse_hold_msec",            &settings->uints.input_overlay_mouse_hold_msec, true, DEFAULT_INPUT_OVERLAY_MOUSE_HOLD_MSEC, false);
    SETTING_UINT("input_overlay_mouse_dtap_msec",            &settings->uints.input_overlay_mouse_dtap_msec, true, DEFAULT_INPUT_OVERLAY_MOUSE_DTAP_MSEC, false);
+   SETTING_UINT("input_overlay_mouse_alt_two_touch_input",  &settings->uints.input_overlay_mouse_alt_two_touch_input, true, DEFAULT_INPUT_OVERLAY_MOUSE_ALT_TWO_TOUCH_INPUT, false);
 #endif
 
    *size = count;
diff --git a/configuration.h b/configuration.h
@@ -355,6 +355,7 @@ typedef struct settings
       unsigned input_overlay_lightgun_four_touch_input;
       unsigned input_overlay_mouse_hold_msec;
       unsigned input_overlay_mouse_dtap_msec;
+      unsigned input_overlay_mouse_alt_two_touch_input;
 #endif
 
       unsigned run_ahead_frames;
diff --git a/input/input_driver.c b/input/input_driver.c
@@ -3199,7 +3199,7 @@ void input_overlay_auto_rotate_(
 
 /**
  * input_overlay_poll_lightgun
- * @settings: pointer to settings
+ * @settings : pointer to settings
  * @ol : overlay handle
  * @old_ptr_count : previous poll's non-hitbox pointer count
  *
@@ -3319,8 +3319,10 @@ static void input_overlay_get_mouse_scale(settings_t *settings,
 
 /**
  * input_overlay_poll_mouse
- * @settings: pointer to settings
+ * @settings : pointer to settings
+ * @mouse_st : pointer to overlay mouse state
  * @ol : overlay handle
+ * @ptr_count : this poll's non-hitbox pointer count
  * @old_ptr_count : previous poll's non-hitbox pointer count
  *
  * Updates button state of the overlay mouse.
@@ -3331,15 +3333,16 @@ static void input_overlay_poll_mouse(settings_t *settings,
       const int ptr_count,
       const int old_ptr_count)
 {
-   input_overlay_pointer_state_t *ptr_st      = &ol->pointer_state;
-   const retro_time_t now_usec                = cpu_features_get_time_usec();
-   const retro_time_t hold_usec               = settings->uints.input_overlay_mouse_hold_msec * 1000;
-   const retro_time_t dtap_usec               = settings->uints.input_overlay_mouse_dtap_msec * 1000;
-   int swipe_thres_x                          = 0;
-   int swipe_thres_y                          = 0;
-   const bool hold_to_drag                    = settings->bools.input_overlay_mouse_hold_to_drag;
-   const bool dtap_to_drag                    = settings->bools.input_overlay_mouse_dtap_to_drag;
-   bool want_feedback                         = false;
+   input_overlay_pointer_state_t *ptr_st = &ol->pointer_state;
+   const retro_time_t now_usec           = cpu_features_get_time_usec();
+   const retro_time_t hold_usec          = settings->uints.input_overlay_mouse_hold_msec * 1000;
+   const retro_time_t dtap_usec          = settings->uints.input_overlay_mouse_dtap_msec * 1000;
+   const uint8_t alt_2touch              = settings->uints.input_overlay_mouse_alt_two_touch_input;
+   int swipe_thres_x                     = 0;
+   int swipe_thres_y                     = 0;
+   const bool hold_to_drag               = settings->bools.input_overlay_mouse_hold_to_drag;
+   const bool dtap_to_drag               = settings->bools.input_overlay_mouse_dtap_to_drag;
+   bool want_feedback                    = false;
    bool is_swipe, is_brief, is_long;
 
    static retro_time_t start_usec;
@@ -3352,8 +3355,10 @@ static void input_overlay_poll_mouse(settings_t *settings,
    static int y_start;
    static int peak_ptr_count;
    static int old_peak_ptr_count;
-   static bool skip_buttons;
+   static bool check_gestures;
    static bool pending_click;
+   static const uint8_t btns[OVERLAY_MAX_TOUCH + 1] =
+         {0x0, 0x1, 0x2, 0x4};  /* none, lmb, rmb, mmb */
 
    input_overlay_get_mouse_scale(settings,
          (float*)&mouse_st->scale_x, &mouse_st->scale_y,
@@ -3374,6 +3379,11 @@ static void input_overlay_poll_mouse(settings_t *settings,
          /* Pointer added */
          peak_ptr_count = ptr_count;
          start_usec     = now_usec;
+
+         /* Alt 2-touch input. After gesture checks,
+          * use 2nd touch as a button */
+         if (!check_gestures && ptr_count == 2)
+            mouse_st->hold = btns[alt_2touch];
       }
       else
       {
@@ -3391,15 +3401,15 @@ static void input_overlay_poll_mouse(settings_t *settings,
    is_long  = (now_usec - start_usec) > (hold_to_drag ? hold_usec : 250000);
 
    /* Check if new button input should be created */
-   if (!skip_buttons)
+   if (check_gestures)
    {
       if (!is_swipe)
       {
          if (     hold_to_drag
                && is_long && ptr_count && !mouse_st->hold)
          {
             /* Long press */
-            mouse_st->hold = (1 << (ptr_count - 1));
+            mouse_st->hold = btns[ptr_count];
             want_feedback  = true;
          }
          else if (is_brief)
@@ -3409,7 +3419,7 @@ static void input_overlay_poll_mouse(settings_t *settings,
                /* New input. Check for double tap */
                if (     dtap_to_drag
                      && now_usec - last_up_usec < dtap_usec)
-                  mouse_st->hold = (1 << (old_peak_ptr_count - 1));
+                  mouse_st->hold = btns[old_peak_ptr_count];
 
                last_down_usec = now_usec;
             }
@@ -3425,7 +3435,7 @@ static void input_overlay_poll_mouse(settings_t *settings,
                }
                else
                {
-                  mouse_st->click    = (1 << (peak_ptr_count - 1));
+                  mouse_st->click    = btns[peak_ptr_count];
                   click_end_usec     = now_usec + click_dur_usec;
                }
 
@@ -3435,14 +3445,19 @@ static void input_overlay_poll_mouse(settings_t *settings,
       }
       else
       {
-         /* If dragging 2+ fingers, hold RMB or MMB */
+         /* Swiping. Stop gesture checks and possibly hold a button */
          if (ptr_count > 1)
          {
-            mouse_st->hold = (1 << (ptr_count - 1));
-            if (hold_to_drag)
+            if (hold_to_drag && !alt_2touch)
+            {
+               mouse_st->hold = btns[ptr_count];
                want_feedback = true;
+            }
+            else if (alt_2touch && !hold_to_drag
+                  && ptr_count == 2)
+               mouse_st->hold = btns[alt_2touch];
          }
-         skip_buttons = true;
+         check_gestures = false;
       }
    }
 
@@ -3455,9 +3470,9 @@ static void input_overlay_poll_mouse(settings_t *settings,
    }
 
    if (!ptr_count)
-      skip_buttons = false; /* Reset button checks  */
+      check_gestures = true;
    else if (is_long)
-      skip_buttons = true;  /* End of button checks */
+      check_gestures = false;
 
    /* Remove stale clicks */
    if (mouse_st->click && now_usec > click_end_usec)
diff --git a/input/input_overlay.h b/input/input_overlay.h
@@ -161,6 +161,16 @@ enum overlay_lightgun_action
    OVERLAY_LIGHTGUN_ACTION_END
 };
 
+enum overlay_mouse_button
+{
+   OVERLAY_MOUSE_BTN_NONE = 0,
+   OVERLAY_MOUSE_BTN_LMB,
+   OVERLAY_MOUSE_BTN_RMB,
+   OVERLAY_MOUSE_BTN_MMB,
+
+   OVERLAY_MOUSE_BTN_END
+};
+
 /* Overlay driver acts as a medium between input drivers
  * and video driver.
  *
diff --git a/intl/msg_hash_lbl.h b/intl/msg_hash_lbl.h
@@ -2142,6 +2142,10 @@ MSG_HASH(
    MENU_ENUM_LABEL_INPUT_OVERLAY_MOUSE_SWIPE_THRESHOLD,
    "input_overlay_mouse_swipe_threshold"
    )
+MSG_HASH(
+   MENU_ENUM_LABEL_INPUT_OVERLAY_MOUSE_ALT_TWO_TOUCH_INPUT,
+   "input_overlay_mouse_alt_two_touch_input"
+   )
 MSG_HASH(
    MENU_ENUM_LABEL_INPUT_OVERLAY_DPAD_DIAGONAL_SENSITIVITY,
    "input_overlay_dpad_diagonal_sensitivity"
diff --git a/intl/msg_hash_us.h b/intl/msg_hash_us.h
@@ -5885,6 +5885,14 @@ MSG_HASH(
    MENU_ENUM_LABEL_VALUE_INPUT_OVERLAY_MOUSE_SWIPE_THRESHOLD,
    "Swipe Threshold"
    )
+MSG_HASH(
+   MENU_ENUM_LABEL_VALUE_INPUT_OVERLAY_MOUSE_ALT_TWO_TOUCH_INPUT,
+   "Alt 2-Touch Input"
+   )
+MSG_HASH(
+   MENU_ENUM_SUBLABEL_INPUT_OVERLAY_MOUSE_ALT_TWO_TOUCH_INPUT,
+   "Use second touch as a mouse button while controlling the cursor."
+   )
 MSG_HASH(
    MENU_ENUM_SUBLABEL_INPUT_OVERLAY_MOUSE_SWIPE_THRESHOLD,
    "Adjust the allowable drift range when detecting a long press or tap. Expressed as a percentage of the smaller screen dimension."
diff --git a/menu/cbs/menu_cbs_sublabel.c b/menu/cbs/menu_cbs_sublabel.c
@@ -926,6 +926,7 @@ DEFAULT_SUBLABEL_MACRO(action_bind_sublabel_input_overlay_mouse_hold_msec,
 DEFAULT_SUBLABEL_MACRO(action_bind_sublabel_input_overlay_mouse_dtap_to_drag,         MENU_ENUM_SUBLABEL_INPUT_OVERLAY_MOUSE_DTAP_TO_DRAG)
 DEFAULT_SUBLABEL_MACRO(action_bind_sublabel_input_overlay_mouse_dtap_msec,            MENU_ENUM_SUBLABEL_INPUT_OVERLAY_MOUSE_DTAP_MSEC)
 DEFAULT_SUBLABEL_MACRO(action_bind_sublabel_input_overlay_mouse_swipe_threshold,      MENU_ENUM_SUBLABEL_INPUT_OVERLAY_MOUSE_SWIPE_THRESHOLD)
+DEFAULT_SUBLABEL_MACRO(action_bind_sublabel_input_overlay_mouse_alt_two_touch_input,  MENU_ENUM_SUBLABEL_INPUT_OVERLAY_MOUSE_ALT_TWO_TOUCH_INPUT)
 DEFAULT_SUBLABEL_MACRO(action_bind_sublabel_netplay_public_announce,       MENU_ENUM_SUBLABEL_NETPLAY_PUBLIC_ANNOUNCE)
 DEFAULT_SUBLABEL_MACRO(action_bind_sublabel_netplay_ip_address,            MENU_ENUM_SUBLABEL_NETPLAY_IP_ADDRESS)
 DEFAULT_SUBLABEL_MACRO(action_bind_sublabel_netplay_tcp_udp_port,          MENU_ENUM_SUBLABEL_NETPLAY_TCP_UDP_PORT)
@@ -3994,6 +3995,9 @@ int menu_cbs_init_bind_sublabel(menu_file_list_cbs_t *cbs,
          case MENU_ENUM_LABEL_INPUT_OVERLAY_MOUSE_SWIPE_THRESHOLD:
             BIND_ACTION_SUBLABEL(cbs, action_bind_sublabel_input_overlay_mouse_swipe_threshold);
             break;
+         case MENU_ENUM_LABEL_INPUT_OVERLAY_MOUSE_ALT_TWO_TOUCH_INPUT:
+            BIND_ACTION_SUBLABEL(cbs, action_bind_sublabel_input_overlay_mouse_alt_two_touch_input);
+            break;
          case MENU_ENUM_LABEL_AUDIO_DSP_PLUGIN:
             BIND_ACTION_SUBLABEL(cbs, action_bind_sublabel_audio_dsp_plugin);
             break;
diff --git a/menu/menu_displaylist.c b/menu/menu_displaylist.c
@@ -10681,6 +10681,10 @@ unsigned menu_displaylist_build_list(
                   MENU_ENUM_LABEL_INPUT_OVERLAY_MOUSE_SWIPE_THRESHOLD,
                   PARSE_ONLY_FLOAT, false) == 0)
             count++;
+         if (MENU_DISPLAYLIST_PARSE_SETTINGS_ENUM(list,
+                  MENU_ENUM_LABEL_INPUT_OVERLAY_MOUSE_ALT_TWO_TOUCH_INPUT,
+                  PARSE_ONLY_UINT, false) == 0)
+            count++;
          break;
 #endif
       case DISPLAYLIST_LATENCY_SETTINGS_LIST:
diff --git a/menu/menu_setting.c b/menu/menu_setting.c
@@ -5515,6 +5515,31 @@ static size_t setting_get_string_representation_overlay_lightgun_action(
    }
    return 0;
 }
+
+static size_t setting_get_string_representation_overlay_mouse_btn(
+      rarch_setting_t *setting, char *s, size_t len)
+{
+   if (setting)
+   {
+      switch (*setting->value.target.unsigned_integer)
+      {
+         case OVERLAY_MOUSE_BTN_NONE:
+            return strlcpy(s, msg_hash_to_str(
+                     MENU_ENUM_LABEL_VALUE_NONE), len);
+         case OVERLAY_MOUSE_BTN_LMB:
+            return strlcpy(s, msg_hash_to_str(
+                     MENU_ENUM_LABEL_VALUE_INPUT_MOUSE_LEFT), len);
+         case OVERLAY_MOUSE_BTN_RMB:
+            return strlcpy(s, msg_hash_to_str(
+                     MENU_ENUM_LABEL_VALUE_INPUT_MOUSE_RIGHT), len);
+         case OVERLAY_MOUSE_BTN_MMB:
+            return strlcpy(s, msg_hash_to_str(
+                     MENU_ENUM_LABEL_VALUE_INPUT_MOUSE_MIDDLE), len);
+      }
+   }
+
+   return 0;
+}
 #endif
 
 /* A protected driver is such that the user cannot set to "null" using the UI.
@@ -18171,6 +18196,23 @@ static bool setting_append_list(
          (*list)[list_info->index - 1].action_ok = &setting_action_ok_uint;
          menu_settings_list_current_add_range(list, list_info, 0.0, 10.0, 0.1, true, true);
 
+         CONFIG_UINT(
+               list, list_info,
+               &settings->uints.input_overlay_mouse_alt_two_touch_input,
+               MENU_ENUM_LABEL_INPUT_OVERLAY_MOUSE_ALT_TWO_TOUCH_INPUT,
+               MENU_ENUM_LABEL_VALUE_INPUT_OVERLAY_MOUSE_ALT_TWO_TOUCH_INPUT,
+               DEFAULT_INPUT_OVERLAY_MOUSE_ALT_TWO_TOUCH_INPUT,
+               &group_info,
+               &subgroup_info,
+               parent_group,
+               general_write_handler,
+               general_read_handler);
+         (*list)[list_info->index - 1].action_ok = &setting_action_ok_uint;
+         (*list)[list_info->index - 1].get_string_representation =
+               &setting_get_string_representation_overlay_mouse_btn;
+         menu_settings_list_current_add_range(list, list_info,
+               OVERLAY_MOUSE_BTN_NONE, OVERLAY_MOUSE_BTN_END - 1, 1, true, true);
+
          END_SUB_GROUP(list, list_info, parent_group);
 
          END_GROUP(list, list_info, parent_group);
diff --git a/msg_hash.h b/msg_hash.h
@@ -1396,6 +1396,7 @@ enum msg_hash_enums
    MENU_LABEL(INPUT_OVERLAY_MOUSE_DTAP_TO_DRAG),
    MENU_LABEL(INPUT_OVERLAY_MOUSE_DTAP_MSEC),
    MENU_LABEL(INPUT_OVERLAY_MOUSE_SWIPE_THRESHOLD),
+   MENU_LABEL(INPUT_OVERLAY_MOUSE_ALT_TWO_TOUCH_INPUT),
    MENU_LABEL(INPUT_KEYBOARD_GAMEPAD_MAPPING_TYPE),
    MENU_LABEL(INPUT_SMALL_KEYBOARD_ENABLE),
    MENU_LABEL(INPUT_TOUCH_ENABLE),
