WindowsGamepad.cpp

#include "WindowsGamepad.h"
 
#include "ViewContext.h"
 
#include "Input/InputManager.h"
#include "Input/GamepadMapping.h"
 
#include "Services/Time.h"
 
#define WIN32_LEAN_AND_MEAN
#include <Windows.h>
#include <xinput.h>
 
#pragma comment(lib, "Xinput9_1_0.lib")
 
void Cogs::Platform::GamepadHandler::initialize(Core::ViewContext* viewContext) {
  view = viewContext;
 
  mapping.fill(NoMapping);
  checkedTime.fill(0);
}
 
void Cogs::Platform::GamepadHandler::update()
{
  Core::InputManager* inputManager = view->inputManager.get();
  const double        t = view->getContext()->time->getAnimationTime();
 
  for (int i = 0; i < XUSER_MAX_COUNT; ++i) {
    if (mapping[i] == Disconnected && (t - checkedTime[i]) < checkInterval) continue;
 
    XINPUT_STATE xState = {};
    auto result = XInputGetState(DWORD(i), &xState);
 
    if (result != ERROR_SUCCESS) {
      if (mapping[i] == Connected) {
        auto & state = inputManager->getDevice((Core::InputDevices::EValues)(Core::InputDevices::Gamepad0 + i));
 
        state.isConnected = false;
      }
 
      mapping[i] = Disconnected;
      checkedTime[i] = t + i * 0.1; // Slightly shift to displace over multiple frames.
 
      continue;
    }
 
    auto & state = inputManager->getDevice((Core::InputDevices::EValues)(Core::InputDevices::Gamepad0 + i));
 
    if (mapping[i] == NoMapping) {
      if (state.isConnected) {
        // Someone has already grabbed this. Warning/Error.
        continue;
      }
 
      // Connected new controller.
 
      state.axisMask = 0x000000000000003F;
      state.buttonMask = 0x000000000000FFFF;
 
      state.isConnected = true;
 
      mapping[i] = Connected;
    }
 
    for (size_t ii = 0; ii < 16; ++ii) {
      state.setButton(ii, (xState.Gamepad.wButtons & (1 << ii)) != 0);
    }
 
    state.setAxis(Core::Gamepad::TriggerLeft, (float)xState.Gamepad.bLeftTrigger / 255.0f);
    state.setAxis(Core::Gamepad::TriggerRight, (float)xState.Gamepad.bRightTrigger / 255.0f);
 
    //NOTE: Difference between positive/negative max values of signed shorts. We could use clamped normalization
    //here like the graphics APIs.
    const float positiveRange = 32768 - 1;
    const float negativeRange = 32768;
 
    state.setAxis(Core::Gamepad::StickLeftX, (float)xState.Gamepad.sThumbLX / (xState.Gamepad.sThumbLX > 0 ? positiveRange : negativeRange));
    state.setAxis(Core::Gamepad::StickLeftY, (float)xState.Gamepad.sThumbLY / (xState.Gamepad.sThumbLY > 0 ? positiveRange : negativeRange));
    state.setAxis(Core::Gamepad::StickRightX, (float)xState.Gamepad.sThumbRX / (xState.Gamepad.sThumbRX > 0 ? positiveRange : negativeRange));
    state.setAxis(Core::Gamepad::StickRightY, (float)xState.Gamepad.sThumbRY / (xState.Gamepad.sThumbRY > 0 ? positiveRange : negativeRange));
 
    state.isValid = true;
  }
}