Line data    Source code

       1             : /* Copyright (C) 2021 Wildfire Games.
       2             :  * This file is part of 0 A.D.
       3             :  *
       4             :  * 0 A.D. is free software: you can redistribute it and/or modify
       5             :  * it under the terms of the GNU General Public License as published by
       6             :  * the Free Software Foundation, either version 2 of the License, or
       7             :  * (at your option) any later version.
       8             :  *
       9             :  * 0 A.D. is distributed in the hope that it will be useful,
      10             :  * but WITHOUT ANY WARRANTY; without even the implied warranty of
      11             :  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      12             :  * GNU General Public License for more details.
      13             :  *
      14             :  * You should have received a copy of the GNU General Public License
      15             :  * along with 0 A.D.  If not, see <http://www.gnu.org/licenses/>.
      16             :  */
      17             : 
      18             : #include "precompiled.h"
      19             : 
      20             : #include "Joystick.h"
      21             : 
      22             : #include "lib/external_libraries/libsdl.h"
      23             : #include "ps/CLogger.h"
      24             : #include "ps/ConfigDB.h"
      25             : 
      26           1 : CJoystick g_Joystick;
      27             : 
      28           1 : CJoystick::CJoystick() :
      29           1 :     m_Joystick(NULL), m_Deadzone(0)
      30             : {
      31           1 : }
      32             : 
      33           1 : void CJoystick::Initialise()
      34             : {
      35           1 :     bool joystickEnable = false;
      36           1 :     if (!CConfigDB::IsInitialised())
      37           2 :         return;
      38           0 :     CFG_GET_VAL("joystick.enable", joystickEnable);
      39           0 :     if (!joystickEnable)
      40           0 :         return;
      41             : 
      42           0 :     CFG_GET_VAL("joystick.deadzone", m_Deadzone);
      43             : 
      44           0 :     if (SDL_InitSubSystem(SDL_INIT_JOYSTICK) < 0)
      45             :     {
      46           0 :         LOGERROR("CJoystick::Initialise failed to initialise joysticks (\"%s\")", SDL_GetError());
      47           0 :         return;
      48             :     }
      49             : 
      50           0 :     int numJoysticks = SDL_NumJoysticks();
      51             : 
      52           0 :     LOGMESSAGE("Found %d joystick(s)", numJoysticks);
      53             : 
      54           0 :     for (int i = 0; i < numJoysticks; ++i)
      55             :     {
      56           0 :         SDL_Joystick* stick = SDL_JoystickOpen(i);
      57           0 :         if (!stick)
      58             :         {
      59           0 :             LOGERROR("CJoystick::Initialise failed to open joystick %d (\"%s\")", i, SDL_GetError());
      60           0 :             continue;
      61             :         }
      62           0 :         const char* name = SDL_JoystickName(stick);
      63           0 :         LOGMESSAGE("Joystick %d: %s", i, name);
      64           0 :         SDL_JoystickClose(stick);
      65             :     }
      66             : 
      67           0 :     if (numJoysticks)
      68             :     {
      69           0 :         SDL_JoystickEventState(SDL_ENABLE);
      70             : 
      71             :         // Always pick the first joystick, and assume that's the right one
      72           0 :         m_Joystick = SDL_JoystickOpen(0);
      73           0 :         if (!m_Joystick)
      74           0 :             LOGERROR("CJoystick::Initialise failed to open joystick (\"%s\")", SDL_GetError());
      75             :     }
      76             : }
      77             : 
      78           0 : bool CJoystick::IsEnabled()
      79             : {
      80           0 :     return (m_Joystick != NULL);
      81             : }
      82             : 
      83           0 : float CJoystick::GetAxisValue(int axis)
      84             : {
      85           0 :     if (!m_Joystick || axis < 0 || axis >= SDL_JoystickNumAxes(m_Joystick))
      86           0 :         return 0.f;
      87             : 
      88           0 :     int16_t val = SDL_JoystickGetAxis(m_Joystick, axis);
      89             : 
      90             :     // Normalize values into the range [-1, +1] excluding the deadzone around 0
      91             :     float norm;
      92           0 :     if (val > m_Deadzone)
      93           0 :         norm = (val - m_Deadzone) / (float)(32767 - m_Deadzone);
      94           0 :     else if (val < -m_Deadzone)
      95           0 :         norm = (val + m_Deadzone) / (float)(32767 - m_Deadzone);
      96             :     else
      97           0 :         norm = 0.f;
      98             : 
      99           0 :     return norm;
     100           3 : }