InputCommon / DolphinQt / Core: Add a "RelativeMouse" input which provides the raw delta mouse input

Co-authored-by: Jordan Woyak <jordan.woyak@gmail.com>

Source/Core/Core/HW/SI/SI.cpp

@@ -655,6 +655,7 @@ void UpdateDevices()
 
   // Update inputs at the rate of SI
   // Typically 120hz but is variable
+  g_controller_interface.SetCurrentInputChannel(ciface::InputChannel::SerialInterface);
   g_controller_interface.UpdateInput();
 
   // Update channels and set the status bit if there's new data

Source/Core/Core/IOS/USB/Bluetooth/BTEmu.cpp

@@ -339,6 +339,7 @@ void BluetoothEmuDevice::Update()
 
   if (now - m_last_ticks > interval)
   {
+    g_controller_interface.SetCurrentInputChannel(ciface::InputChannel::Bluetooth);
     g_controller_interface.UpdateInput();
     for (auto& wiimote : m_wiimotes)
       wiimote->UpdateInput();

Source/Core/DolphinQt/HotkeyScheduler.cpp

@@ -141,8 +141,8 @@ void HotkeyScheduler::Run()
   {
     Common::SleepCurrentThread(1000 / 60);
 
-    if (Core::GetState() == Core::State::Uninitialized || Core::GetState() == Core::State::Paused)
-      g_controller_interface.UpdateInput();
+    g_controller_interface.SetCurrentInputChannel(ciface::InputChannel::Host);
+    g_controller_interface.UpdateInput();
 
     if (!HotkeyManagerEmu::IsEnabled())
       continue;

Source/Core/InputCommon/ControllerInterface/ControllerInterface.cpp

@@ -37,6 +37,8 @@
 
 ControllerInterface g_controller_interface;
 
+static thread_local ciface::InputChannel tls_input_channel = ciface::InputChannel::Host;
+
 void ControllerInterface::Initialize(const WindowSystemInfo& wsi)
 {
   if (m_is_init)
@@ -274,6 +276,16 @@ void ControllerInterface::UpdateInput()
   }
 }
 
+void ControllerInterface::SetCurrentInputChannel(ciface::InputChannel input_channel)
+{
+  tls_input_channel = input_channel;
+}
+
+ciface::InputChannel ControllerInterface::GetCurrentInputChannel()
+{
+  return tls_input_channel;
+}
+
 void ControllerInterface::SetAspectRatioAdjustment(float value)
 {
   m_aspect_ratio_adjustment = value;

Source/Core/InputCommon/ControllerInterface/ControllerInterface.h

@@ -32,6 +32,23 @@
 #endif
 #define CIFACE_USE_DUALSHOCKUDPCLIENT
 
+namespace ciface
+{
+// A thread local "input channel" is maintained to handle the state of relative inputs.
+// This allows simultaneous use of relative inputs across different input contexts.
+// e.g. binding relative mouse movements to both GameCube controllers and FreeLook.
+// These operate at different rates and processing one would break the other without separate state.
+enum class InputChannel
+{
+  Host,
+  SerialInterface,
+  Bluetooth,
+  FreeLook,
+  Count,
+};
+
+}  // namespace ciface
+
 //
 // ControllerInterface
 //
@@ -66,6 +83,9 @@ public:
   void UnregisterDevicesChangedCallback(const HotplugCallbackHandle& handle);
   void InvokeDevicesChangedCallbacks() const;
 
+  static void SetCurrentInputChannel(ciface::InputChannel);
+  static ciface::InputChannel GetCurrentInputChannel();
+
 private:
   std::list<std::function<void()>> m_devices_changed_callbacks;
   mutable std::mutex m_callbacks_mutex;
@@ -75,4 +95,37 @@ private:
   std::atomic<float> m_aspect_ratio_adjustment = 1;
 };
 
+namespace ciface
+{
+template <typename T>
+class RelativeInputState
+{
+public:
+  void Update()
+  {
+    const auto channel = int(ControllerInterface::GetCurrentInputChannel());
+
+    m_value[channel] = m_delta[channel];
+    m_delta[channel] = {};
+  }
+
+  T GetValue() const
+  {
+    const auto channel = int(ControllerInterface::GetCurrentInputChannel());
+
+    return m_value[channel];
+  }
+
+  void Move(T delta)
+  {
+    for (auto& d : m_delta)
+      d += delta;
+  }
+
+private:
+  std::array<T, int(InputChannel::Count)> m_value;
+  std::array<T, int(InputChannel::Count)> m_delta;
+};
+}  // namespace ciface
+
 extern ControllerInterface g_controller_interface;

Source/Core/InputCommon/ControllerInterface/CoreDevice.h

@@ -93,6 +93,12 @@ public:
     virtual bool IsChild(const Input*) const { return false; }
   };
 
+  class RelativeInput : public Input
+  {
+  public:
+    bool IsDetectable() const override { return false; }
+  };
+
   //
   // Output
   //

Source/Core/InputCommon/ControllerInterface/DInput/DInputKeyboardMouse.cpp

@@ -2,11 +2,14 @@
 // Licensed under GPLv2+
 // Refer to the license.txt file included.
 
+#include "InputCommon/ControllerInterface/DInput/DInputKeyboardMouse.h"
+
 #include <algorithm>
 
+#include <fmt/format.h>
+
 #include "InputCommon/ControllerInterface/ControllerInterface.h"
 #include "InputCommon/ControllerInterface/DInput/DInput.h"
-#include "InputCommon/ControllerInterface/DInput/DInputKeyboardMouse.h"
 
 // (lower would be more sensitive) user can lower sensitivity by setting range
 // seems decent here ( at 8 ), I don't think anyone would need more sensitive than this
@@ -19,6 +22,30 @@
 
 namespace ciface::DInput
 {
+class RelativeMouseAxis final : public Core::Device::RelativeInput
+{
+public:
+  std::string GetName() const override
+  {
+    return fmt::format("RelativeMouse {}{}", char('X' + m_index), (m_scale > 0) ? '+' : '-');
+  }
+
+  RelativeMouseAxis(u8 index, bool positive, const RelativeMouseState* state)
+      : m_state(*state), m_index(index), m_scale(positive * 2 - 1)
+  {
+  }
+
+  ControlState GetState() const override
+  {
+    return ControlState(m_state.GetValue().data[m_index] * m_scale);
+  }
+
+private:
+  const RelativeMouseState& m_state;
+  const u8 m_index;
+  const s8 m_scale;
+};
+
 static const struct
 {
   const BYTE code;
@@ -108,9 +135,17 @@ KeyboardMouse::KeyboardMouse(const LPDIRECTINPUTDEVICE8 kb_device,
     AddInput(new Axis(i, ax, (2 == i) ? -1 : -MOUSE_AXIS_SENSITIVITY));
     AddInput(new Axis(i, ax, -(2 == i) ? 1 : MOUSE_AXIS_SENSITIVITY));
   }
+
   // cursor, with a hax for-loop
   for (unsigned int i = 0; i < 4; ++i)
     AddInput(new Cursor(!!(i & 2), (&m_state_in.cursor.x)[i / 2], !!(i & 1)));
+
+  // Raw relative mouse movement.
+  for (unsigned int i = 0; i != mouse_caps.dwAxes; ++i)
+  {
+    AddInput(new RelativeMouseAxis(i, false, &m_state_in.relative_mouse));
+    AddInput(new RelativeMouseAxis(i, true, &m_state_in.relative_mouse));
+  }
 }
 
 void KeyboardMouse::UpdateCursorInput()
@@ -147,6 +182,8 @@ void KeyboardMouse::UpdateInput()
   {
     // set axes to zero
     m_state_in.mouse = {};
+    m_state_in.relative_mouse = {};
+
     // skip this input state
     m_mo_device->GetDeviceState(sizeof(tmp_mouse), &tmp_mouse);
   }
@@ -162,14 +199,17 @@ void KeyboardMouse::UpdateInput()
   if (DIERR_INPUTLOST == mo_hr || DIERR_NOTACQUIRED == mo_hr)
     m_mo_device->Acquire();
 
-  if (SUCCEEDED(kb_hr) && SUCCEEDED(mo_hr))
+  if (SUCCEEDED(mo_hr))
   {
+    m_state_in.relative_mouse.Move({tmp_mouse.lX, tmp_mouse.lY, tmp_mouse.lZ});
+    m_state_in.relative_mouse.Update();
+
     // need to smooth out the axes, otherwise it doesn't work for shit
     for (unsigned int i = 0; i < 3; ++i)
       ((&m_state_in.mouse.lX)[i] += (&tmp_mouse.lX)[i]) /= 2;
 
     // copy over the buttons
-    memcpy(m_state_in.mouse.rgbButtons, tmp_mouse.rgbButtons, sizeof(m_state_in.mouse.rgbButtons));
+    std::copy_n(tmp_mouse.rgbButtons, std::size(tmp_mouse.rgbButtons), m_state_in.mouse.rgbButtons);
 
     UpdateCursorInput();
   }

Source/Core/InputCommon/ControllerInterface/DInput/DInputKeyboardMouse.h

@@ -7,6 +7,7 @@
 #include <windows.h>
 
 #include "Common/Matrix.h"
+#include "InputCommon/ControllerInterface/ControllerInterface.h"
 #include "InputCommon/ControllerInterface/CoreDevice.h"
 #include "InputCommon/ControllerInterface/DInput/DInput8.h"
 
@@ -14,14 +15,23 @@ namespace ciface::DInput
 {
 void InitKeyboardMouse(IDirectInput8* const idi8, HWND hwnd);
 
+using RelativeMouseState = RelativeInputState<Common::TVec3<LONG>>;
+
 class KeyboardMouse : public Core::Device
 {
 private:
   struct State
   {
     BYTE keyboard[256];
+
+    // Old smoothed relative mouse movement.
     DIMOUSESTATE2 mouse;
+
+    // Normalized mouse cursor position.
     Common::TVec2<ControlState> cursor;
+
+    // Raw relative mouse movement.
+    RelativeMouseState relative_mouse;
   };
 
   class Key : public Input
@@ -53,6 +63,7 @@ private:
   public:
     Axis(u8 index, const LONG& axis, LONG range) : m_axis(axis), m_range(range), m_index(index) {}
     std::string GetName() const override;
+    bool IsDetectable() const override { return false; }
     ControlState GetState() const override;
 
   private:

Source/Core/InputCommon/ControllerInterface/Xlib/XInput2.cpp

@@ -197,6 +197,11 @@ KeyboardMouse::KeyboardMouse(Window window, int opcode, int pointer, int keyboar
   // Mouse Axis, X-/+ and Y-/+
   for (int i = 0; i != 4; ++i)
     AddInput(new Axis(!!(i & 2), !!(i & 1), (i & 2) ? &m_state.axis.y : &m_state.axis.x));
+
+  // Relative Mouse, X-/+ and Y-/+
+  for (int i = 0; i != 4; ++i)
+    AddInput(new RelativeMouse(!!(i & 2), !!(i & 1),
+                               (i & 2) ? &m_state.relative_mouse.y : &m_state.relative_mouse.x));
 }
 
 KeyboardMouse::~KeyboardMouse()
@@ -302,6 +307,9 @@ void KeyboardMouse::UpdateInput()
     XFreeEventData(m_display, &event.xcookie);
   }
 
+  m_state.relative_mouse.x = delta_x;
+  m_state.relative_mouse.y = delta_y;
+
   // apply axis smoothing
   m_state.axis.x *= MOUSE_AXIS_SMOOTHING;
   m_state.axis.x += delta_x;
@@ -391,8 +399,20 @@ KeyboardMouse::Axis::Axis(u8 index, bool positive, const float* axis)
   name = fmt::format("Axis {}{}", static_cast<char>('X' + m_index), (m_positive ? '+' : '-'));
 }
 
+KeyboardMouse::RelativeMouse::RelativeMouse(u8 index, bool positive, const float* axis)
+    : m_axis(axis), m_index(index), m_positive(positive)
+{
+  name =
+      fmt::format("RelativeMouse {}{}", static_cast<char>('X' + m_index), (m_positive ? '+' : '-'));
+}
+
 ControlState KeyboardMouse::Axis::GetState() const
 {
   return std::max(0.0f, *m_axis / (m_positive ? MOUSE_AXIS_SENSITIVITY : -MOUSE_AXIS_SENSITIVITY));
 }
+
+ControlState KeyboardMouse::RelativeMouse::GetState() const
+{
+  return std::max(0.0f, *m_axis / (m_positive ? MOUSE_AXIS_SENSITIVITY : -MOUSE_AXIS_SENSITIVITY));
+}
 }  // namespace ciface::XInput2

Source/Core/InputCommon/ControllerInterface/Xlib/XInput2.h

@@ -30,6 +30,7 @@ private:
     unsigned int buttons;
     Common::Vec2 cursor;
     Common::Vec2 axis;
+    Common::Vec2 relative_mouse;
   };
 
   class Key : public Input
@@ -91,6 +92,21 @@ private:
     std::string name;
   };
 
+  class RelativeMouse : public Input
+  {
+  public:
+    std::string GetName() const override { return name; }
+    bool IsDetectable() const override { return false; }
+    RelativeMouse(u8 index, bool positive, const float* axis);
+    ControlState GetState() const override;
+
+  private:
+    const float* m_axis;
+    const u8 m_index;
+    const bool m_positive;
+    std::string name;
+  };
+
 private:
   void SelectEventsForDevice(XIEventMask* mask, int deviceid);
   void UpdateCursor();