Use finger source when a pointer is simulated

For pinch-to-zoom, rotation and tilt simulation, always use a finger
source (instead of a mouse) for both pointers (the real one and the
simulated one).

A "virtual" mouse does not work on all devices (e.g. on Pixel 8).

PR #5076 <#5076>

app/src/input_manager.c

@@ -365,7 +365,7 @@ simulate_virtual_finger(struct sc_input_manager *im,
     msg.inject_touch_event.action = action;
     msg.inject_touch_event.position.screen_size = im->screen->frame_size;
     msg.inject_touch_event.position.point = point;
-    msg.inject_touch_event.pointer_id = SC_POINTER_ID_VIRTUAL_MOUSE;
+    msg.inject_touch_event.pointer_id = SC_POINTER_ID_VIRTUAL_FINGER;
     msg.inject_touch_event.pressure = up ? 0.0f : 1.0f;
     msg.inject_touch_event.action_button = 0;
     msg.inject_touch_event.buttons = 0;
@@ -650,7 +650,8 @@ sc_input_manager_process_mouse_motion(struct sc_input_manager *im,
 
     struct sc_mouse_motion_event evt = {
         .position = sc_input_manager_get_position(im, event->x, event->y),
-        .pointer_id = SC_POINTER_ID_MOUSE,
+        .pointer_id = im->vfinger_down ? SC_POINTER_ID_GENERIC_FINGER
+                                       : SC_POINTER_ID_MOUSE,
         .xrel = event->xrel,
         .yrel = event->yrel,
         .buttons_state =
@@ -800,11 +801,20 @@ sc_input_manager_process_mouse_button(struct sc_input_manager *im,
 
     uint32_t sdl_buttons_state = SDL_GetMouseState(NULL, NULL);
 
+    SDL_Keymod keymod = SDL_GetModState();
+    bool ctrl_pressed = keymod & KMOD_CTRL;
+    bool shift_pressed = keymod & KMOD_SHIFT;
+    bool change_vfinger = event->button == SDL_BUTTON_LEFT &&
+            ((down && !im->vfinger_down && (ctrl_pressed ^ shift_pressed)) ||
+             (!down && im->vfinger_down));
+    bool use_finger = im->vfinger_down || change_vfinger;
+
     struct sc_mouse_click_event evt = {
         .position = sc_input_manager_get_position(im, event->x, event->y),
         .action = sc_action_from_sdl_mousebutton_type(event->type),
         .button = sc_mouse_button_from_sdl(event->button),
-        .pointer_id = SC_POINTER_ID_MOUSE,
+        .pointer_id = use_finger ? SC_POINTER_ID_GENERIC_FINGER
+                                 : SC_POINTER_ID_MOUSE,
         .buttons_state = sc_mouse_buttons_state_from_sdl(sdl_buttons_state,
                                                          &im->mouse_bindings),
     };
@@ -832,12 +842,7 @@ sc_input_manager_process_mouse_button(struct sc_input_manager *im,
     // can be used instead of Ctrl. The "virtual finger" has a position
     // inverted with respect to the vertical axis of symmetry in the middle of
     // the screen.
-    SDL_Keymod keymod = SDL_GetModState();
-    bool ctrl_pressed = keymod & KMOD_CTRL;
-    bool shift_pressed = keymod & KMOD_SHIFT;
-    if (event->button == SDL_BUTTON_LEFT &&
-            ((down && !im->vfinger_down && (ctrl_pressed ^ shift_pressed)) ||
-             (!down && im->vfinger_down))) {
+    if (change_vfinger) {
         struct sc_point mouse =
             sc_screen_convert_window_to_frame_coords(im->screen, event->x,
                                                                  event->y);