From 3cd3e84486a54d8c53d89ed2aaf23e5931821443 Mon Sep 17 00:00:00 2001
From: Jordan Woyak <jordan.woyak@gmail.com>
Date: Mon, 21 Jan 2019 19:00:09 -0600
Subject: [PATCH] SI_DeviceGCController: Calibrate pad origin on boot to
 perfect neutral values instead of initial input state.

---
 .../Core/Core/HW/SI/SI_DeviceGCController.cpp | 30 +++++--------------
 .../Core/Core/HW/SI/SI_DeviceGCController.h   |  8 ++---
 Source/Core/Core/State.cpp                    |  2 +-
 3 files changed, 12 insertions(+), 28 deletions(-)

diff --git a/Source/Core/Core/HW/SI/SI_DeviceGCController.cpp b/Source/Core/Core/HW/SI/SI_DeviceGCController.cpp
index 441981178e..7e6ee9bd3f 100644
--- a/Source/Core/Core/HW/SI/SI_DeviceGCController.cpp
+++ b/Source/Core/Core/HW/SI/SI_DeviceGCController.cpp
@@ -26,21 +26,14 @@ namespace SerialInterface
 CSIDevice_GCController::CSIDevice_GCController(SIDevices device, int device_number)
     : ISIDevice(device, device_number)
 {
-}
-
-void CSIDevice_GCController::Calibrate()
-{
-  GCPadStatus pad_origin = GetPadStatus();
-  memset(&m_origin, 0, sizeof(SOrigin));
-  m_origin.button = pad_origin.button;
-  m_origin.origin_stick_x = pad_origin.stickX;
-  m_origin.origin_stick_y = pad_origin.stickY;
-  m_origin.substick_x = pad_origin.substickX;
-  m_origin.substick_y = pad_origin.substickY;
-  m_origin.trigger_left = pad_origin.triggerLeft;
-  m_origin.trigger_right = pad_origin.triggerRight;
-
-  m_calibrated = true;
+  // Here we set origin to perfectly centered values.
+  // This purposely differs from real hardware which sets origin to current input state.
+  // That behavior is less than ideal as the user may have inadvertently moved from neutral.
+  // The X+Y+Start button combo can override this if desired.
+  m_origin.origin_stick_x = GCPadStatus::MAIN_STICK_CENTER_X;
+  m_origin.origin_stick_y = GCPadStatus::MAIN_STICK_CENTER_Y;
+  m_origin.substick_x = GCPadStatus::C_STICK_CENTER_X;
+  m_origin.substick_y = GCPadStatus::C_STICK_CENTER_Y;
 }
 
 int CSIDevice_GCController::RunBuffer(u8* buffer, int length)
@@ -87,9 +80,6 @@ int CSIDevice_GCController::RunBuffer(u8* buffer, int length)
   {
     INFO_LOG(SERIALINTERFACE, "PAD - Get Origin");
 
-    if (!m_calibrated)
-      Calibrate();
-
     u8* calibration = reinterpret_cast<u8*>(&m_origin);
     for (int i = 0; i < (int)sizeof(SOrigin); i++)
     {
@@ -103,9 +93,6 @@ int CSIDevice_GCController::RunBuffer(u8* buffer, int length)
   {
     INFO_LOG(SERIALINTERFACE, "PAD - Recalibrate");
 
-    if (!m_calibrated)
-      Calibrate();
-
     u8* calibration = reinterpret_cast<u8*>(&m_origin);
     for (int i = 0; i < (int)sizeof(SOrigin); i++)
     {
@@ -336,7 +323,6 @@ void CSIDevice_GCController::SendCommand(u32 command, u8 poll)
 // Savestate support
 void CSIDevice_GCController::DoState(PointerWrap& p)
 {
-  p.Do(m_calibrated);
   p.Do(m_origin);
   p.Do(m_mode);
   p.Do(m_timer_button_combo_start);
diff --git a/Source/Core/Core/HW/SI/SI_DeviceGCController.h b/Source/Core/Core/HW/SI/SI_DeviceGCController.h
index 8c117ccc3b..b42f574613 100644
--- a/Source/Core/Core/HW/SI/SI_DeviceGCController.h
+++ b/Source/Core/Core/HW/SI/SI_DeviceGCController.h
@@ -65,10 +65,9 @@ protected:
   };
 
   // struct to compare input against
-  // Set on connection and (standard pad only) on button combo
-  SOrigin m_origin;
-
-  bool m_calibrated = false;
+  // Set on connection to perfect neutral values
+  // (standard pad only) Set on button combo to current input state
+  SOrigin m_origin = {};
 
   // PADAnalogMode
   // Dunno if we need to do this, game/lib should set it?
@@ -111,7 +110,6 @@ public:
   static void Rumble(int pad_num, ControlState strength);
 
 protected:
-  void Calibrate();
   void HandleMoviePadStatus(GCPadStatus* pad_status);
 };
 
diff --git a/Source/Core/Core/State.cpp b/Source/Core/Core/State.cpp
index 15c51c7986..65416a5589 100644
--- a/Source/Core/Core/State.cpp
+++ b/Source/Core/Core/State.cpp
@@ -74,7 +74,7 @@ static Common::Event g_compressAndDumpStateSyncEvent;
 static std::thread g_save_thread;
 
 // Don't forget to increase this after doing changes on the savestate system
-static const u32 STATE_VERSION = 99;  // Last changed in PR 6020
+static const u32 STATE_VERSION = 100;  // Last changed in PR 7728
 
 // Maps savestate versions to Dolphin versions.
 // Versions after 42 don't need to be added to this list,