From 38aa485f8f0ae6105ffe1905133966b06b77fe15 Mon Sep 17 00:00:00 2001
From: Connor McLaughlin <stenzek@gmail.com>
Date: Tue, 30 Jun 2020 02:47:47 +1000
Subject: [PATCH] libretro: Analog controller/DualShock support

---
 .../libretro_d3d11_host_display.cpp           |  4 +-
 .../libretro_host_interface.cpp               | 50 ++++++++++++++++++-
 .../libretro_host_interface.h                 |  1 +
 3 files changed, 51 insertions(+), 4 deletions(-)

diff --git a/src/duckstation-libretro/libretro_d3d11_host_display.cpp b/src/duckstation-libretro/libretro_d3d11_host_display.cpp
index b153c90f4..e4004f48c 100644
--- a/src/duckstation-libretro/libretro_d3d11_host_display.cpp
+++ b/src/duckstation-libretro/libretro_d3d11_host_display.cpp
@@ -42,8 +42,8 @@ bool LibretroD3D11HostDisplay::CreateRenderDevice(const WindowInfo& wi, std::str
   else if (ri->interface_type != RETRO_HW_RENDER_INTERFACE_D3D11 ||
            ri->interface_version != RETRO_HW_RENDER_INTERFACE_D3D11_VERSION)
   {
-    Log_ErrorPrint("Unexpected HW interface - type %u version %u", static_cast<unsigned>(ri->interface_type),
-                   static_cast<unsigned>(ri->interface_version));
+    Log_ErrorPrintf("Unexpected HW interface - type %u version %u", static_cast<unsigned>(ri->interface_type),
+                    static_cast<unsigned>(ri->interface_version));
     return false;
   }
 
diff --git a/src/duckstation-libretro/libretro_host_interface.cpp b/src/duckstation-libretro/libretro_host_interface.cpp
index a7000fffa..7ee605f46 100644
--- a/src/duckstation-libretro/libretro_host_interface.cpp
+++ b/src/duckstation-libretro/libretro_host_interface.cpp
@@ -544,9 +544,13 @@ void LibretroHostInterface::UpdateControllers()
         UpdateControllersDigitalController(i);
         break;
 
+      case ControllerType::AnalogController:
+        UpdateControllersAnalogController(i);
+        break;
+
       default:
-        Log_ErrorPrintf("Unhandled controller type '%s'",
-                        Settings::GetControllerTypeDisplayName(m_settings.controller_types[i]));
+        ReportFormattedError("Unhandled controller type '%s'.",
+                             Settings::GetControllerTypeDisplayName(m_settings.controller_types[i]));
         break;
     }
   }
@@ -580,6 +584,48 @@ void LibretroHostInterface::UpdateControllersDigitalController(u32 index)
   }
 }
 
+void LibretroHostInterface::UpdateControllersAnalogController(u32 index)
+{
+  AnalogController* controller = static_cast<AnalogController*>(m_system->GetController(index));
+  DebugAssert(controller);
+
+  static constexpr std::array<std::pair<AnalogController::Button, u32>, 16> button_mapping = {
+    {{AnalogController::Button::Left, RETRO_DEVICE_ID_JOYPAD_LEFT},
+     {AnalogController::Button::Right, RETRO_DEVICE_ID_JOYPAD_RIGHT},
+     {AnalogController::Button::Up, RETRO_DEVICE_ID_JOYPAD_UP},
+     {AnalogController::Button::Down, RETRO_DEVICE_ID_JOYPAD_DOWN},
+     {AnalogController::Button::Circle, RETRO_DEVICE_ID_JOYPAD_A},
+     {AnalogController::Button::Cross, RETRO_DEVICE_ID_JOYPAD_B},
+     {AnalogController::Button::Triangle, RETRO_DEVICE_ID_JOYPAD_X},
+     {AnalogController::Button::Square, RETRO_DEVICE_ID_JOYPAD_Y},
+     {AnalogController::Button::Start, RETRO_DEVICE_ID_JOYPAD_START},
+     {AnalogController::Button::Select, RETRO_DEVICE_ID_JOYPAD_SELECT},
+     {AnalogController::Button::L1, RETRO_DEVICE_ID_JOYPAD_L},
+     {AnalogController::Button::L2, RETRO_DEVICE_ID_JOYPAD_L2},
+     {AnalogController::Button::L3, RETRO_DEVICE_ID_JOYPAD_L3},
+     {AnalogController::Button::R1, RETRO_DEVICE_ID_JOYPAD_R},
+     {AnalogController::Button::R2, RETRO_DEVICE_ID_JOYPAD_R2},
+     {AnalogController::Button::Analog, RETRO_DEVICE_ID_JOYPAD_R3}}};
+
+  static constexpr std::array<std::pair<AnalogController::Axis, std::pair<u32, u32>>, 4> axis_mapping = {
+    {{AnalogController::Axis::LeftX, {RETRO_DEVICE_INDEX_ANALOG_LEFT, RETRO_DEVICE_ID_ANALOG_X}},
+     {AnalogController::Axis::LeftY, {RETRO_DEVICE_INDEX_ANALOG_LEFT, RETRO_DEVICE_ID_ANALOG_Y}},
+     {AnalogController::Axis::RightX, {RETRO_DEVICE_INDEX_ANALOG_RIGHT, RETRO_DEVICE_ID_ANALOG_X}},
+     {AnalogController::Axis::RightY, {RETRO_DEVICE_INDEX_ANALOG_RIGHT, RETRO_DEVICE_ID_ANALOG_Y}}}};
+
+  for (const auto& it : button_mapping)
+  {
+    const int16_t state = g_retro_input_state_callback(index, RETRO_DEVICE_JOYPAD, 0, it.second);
+    controller->SetButtonState(it.first, state != 0);
+  }
+
+  for (const auto& it : axis_mapping)
+  {
+    const int16_t state = g_retro_input_state_callback(index, RETRO_DEVICE_ANALOG, it.second.first, it.second.second);
+    controller->SetAxisState(static_cast<s32>(it.first), std::clamp(static_cast<float>(state) / 32767.0f, -1.0f, 1.0f));
+  }
+}
+
 static std::optional<GPURenderer> RetroHwContextToRenderer(retro_hw_context_type type)
 {
   switch (type)
diff --git a/src/duckstation-libretro/libretro_host_interface.h b/src/duckstation-libretro/libretro_host_interface.h
index 1296efca6..11ecea47a 100644
--- a/src/duckstation-libretro/libretro_host_interface.h
+++ b/src/duckstation-libretro/libretro_host_interface.h
@@ -46,6 +46,7 @@ private:
   void UpdateSettings();
   void UpdateControllers();
   void UpdateControllersDigitalController(u32 index);
+  void UpdateControllersAnalogController(u32 index);
   void GetSystemAVInfo(struct retro_system_av_info* info, bool use_resolution_scale);
   void UpdateSystemAVInfo(bool use_resolution_scale);
   void UpdateGeometry();