// Copyright 2017 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <cmath>
#include <memory>
#include <string>
#include <tuple>
#include <unordered_map>
#include <SDL.h>
#include "common/logging/log.h"
#include "common/math_util.h"
#include "input_common/sdl/sdl.h"
namespace InputCommon {
namespace SDL {
class SDLJoystick;
class SDLButtonFactory;
class SDLAnalogFactory;
static std::unordered_map<int, std::weak_ptr<SDLJoystick>> joystick_list;
static std::shared_ptr<SDLButtonFactory> button_factory;
static std::shared_ptr<SDLAnalogFactory> analog_factory;
static bool initialized = false;
class SDLJoystick {
public:
explicit SDLJoystick(int joystick_index)
: joystick{SDL_JoystickOpen(joystick_index), SDL_JoystickClose} {
if (!joystick) {
LOG_ERROR(Input, "failed to open joystick %d", joystick_index);
}
}
bool GetButton(int button) const {
if (!joystick)
return {};
SDL_JoystickUpdate();
return SDL_JoystickGetButton(joystick.get(), button) == 1;
}
float GetAxis(int axis) const {
if (!joystick)
return {};
SDL_JoystickUpdate();
return SDL_JoystickGetAxis(joystick.get(), axis) / 32767.0f;
}
std::tuple<float, float> GetAnalog(int axis_x, int axis_y) const {
float x = GetAxis(axis_x);
float y = GetAxis(axis_y);
y = -y; // 3DS uses an y-axis inverse from SDL
// Make sure the coordinates are in the unit circle,
// otherwise normalize it.
float r = x * x + y * y;
if (r > 1.0f) {
r = std::sqrt(r);
x /= r;
y /= r;
}
return std::make_tuple(x, y);
}
bool GetHatDirection(int hat, Uint8 direction) const {
return (SDL_JoystickGetHat(joystick.get(), hat) & direction) != 0;
}
private:
std::unique_ptr<SDL_Joystick, decltype(&SDL_JoystickClose)> joystick;
};
class SDLButton final : public Input::ButtonDevice {
public:
explicit SDLButton(std::shared_ptr<SDLJoystick> joystick_, int button_)
: joystick(joystick_), button(button_) {}
bool GetStatus() const override {
return joystick->GetButton(button);
}
private:
std::shared_ptr<SDLJoystick> joystick;
int button;
};
class SDLDirectionButton final : public Input::ButtonDevice {
public:
explicit SDLDirectionButton(std::shared_ptr<SDLJoystick> joystick_, int hat_, Uint8 direction_)
: joystick(joystick_), hat(hat_), direction(direction_) {}
bool GetStatus() const override {
return joystick->GetHatDirection(hat, direction);
}
private:
std::shared_ptr<SDLJoystick> joystick;
int hat;
Uint8 direction;
};
class SDLAxisButton final : public Input::ButtonDevice {
public:
explicit SDLAxisButton(std::shared_ptr<SDLJoystick> joystick_, int axis_, float threshold_,
bool trigger_if_greater_)
: joystick(joystick_), axis(axis_), threshold(threshold_),
trigger_if_greater(trigger_if_greater_) {}
bool GetStatus() const override {
float axis_value = joystick->GetAxis(axis);
if (trigger_if_greater)
return axis_value > threshold;
return axis_value < threshold;
}
private:
std::shared_ptr<SDLJoystick> joystick;
int axis;
float threshold;
bool trigger_if_greater;
};
class SDLAnalog final : public Input::AnalogDevice {
public:
SDLAnalog(std::shared_ptr<SDLJoystick> joystick_, int axis_x_, int axis_y_)
: joystick(joystick_), axis_x(axis_x_), axis_y(axis_y_) {}
std::tuple<float, float> GetStatus() const override {
return joystick->GetAnalog(axis_x, axis_y);
}
private:
std::shared_ptr<SDLJoystick> joystick;
int axis_x;
int axis_y;
};
static std::shared_ptr<SDLJoystick> GetJoystick(int joystick_index) {
std::shared_ptr<SDLJoystick> joystick = joystick_list[joystick_index].lock();
if (!joystick) {
joystick = std::make_shared<SDLJoystick>(joystick_index);
joystick_list[joystick_index] = joystick;
}
return joystick;
}
/// A button device factory that creates button devices from SDL joystick
class SDLButtonFactory final : public Input::Factory<Input::ButtonDevice> {
public:
/**
* Creates a button device from a joystick button
* @param params contains parameters for creating the device:
* - "joystick": the index of the joystick to bind
* - "button"(optional): the index of the button to bind
* - "hat"(optional): the index of the hat to bind as direction buttons
* - "axis"(optional): the index of the axis to bind
* - "direction"(only used for hat): the direction name of the hat to bind. Can be "up",
* "down", "left" or "right"
* - "threshould"(only used for axis): a float value in (-1.0, 1.0) which the button is
* triggered if the axis value crosses
* - "direction"(only used for axis): "+" means the button is triggered when the axis value
* is greater than the threshold; "-" means the button is triggered when the axis value
* is smaller than the threshold
*/
std::unique_ptr<Input::ButtonDevice> Create(const Common::ParamPackage& params) override {
const int joystick_index = params.Get("joystick", 0);
if (params.Has("hat")) {
const int hat = params.Get("hat", 0);
const std::string direction_name = params.Get("direction", "");
Uint8 direction;
if (direction_name == "up") {
direction = SDL_HAT_UP;
} else if (direction_name == "down") {
direction = SDL_HAT_DOWN;
} else if (direction_name == "left") {
direction = SDL_HAT_LEFT;
} else if (direction_name == "right") {
direction = SDL_HAT_RIGHT;
} else {
direction = 0;
}
return std::make_unique<SDLDirectionButton>(GetJoystick(joystick_index), hat,
direction);
}
if (params.Has("axis")) {
const int axis = params.Get("axis", 0);
const float threshold = params.Get("threshold", 0.5f);
const std::string direction_name = params.Get("direction", "");
bool trigger_if_greater;
if (direction_name == "+") {
trigger_if_greater = true;
} else if (direction_name == "-") {
trigger_if_greater = false;
} else {
trigger_if_greater = true;
LOG_ERROR(Input, "Unknown direction %s", direction_name.c_str());
}
return std::make_unique<SDLAxisButton>(GetJoystick(joystick_index), axis, threshold,
trigger_if_greater);
}
const int button = params.Get("button", 0);
return std::make_unique<SDLButton>(GetJoystick(joystick_index), button);
}
};
/// An analog device factory that creates analog devices from SDL joystick
class SDLAnalogFactory final : public Input::Factory<Input::AnalogDevice> {
public:
/**
* Creates analog device from joystick axes
* @param params contains parameters for creating the device:
* - "joystick": the index of the joystick to bind
* - "axis_x": the index of the axis to be bind as x-axis
* - "axis_y": the index of the axis to be bind as y-axis
*/
std::unique_ptr<Input::AnalogDevice> Create(const Common::ParamPackage& params) override {
const int joystick_index = params.Get("joystick", 0);
const int axis_x = params.Get("axis_x", 0);
const int axis_y = params.Get("axis_y", 1);
return std::make_unique<SDLAnalog>(GetJoystick(joystick_index), axis_x, axis_y);
}
};
void Init() {
if (SDL_Init(SDL_INIT_JOYSTICK) < 0) {
LOG_CRITICAL(Input, "SDL_Init(SDL_INIT_JOYSTICK) failed with: %s", SDL_GetError());
} else {
using namespace Input;
RegisterFactory<ButtonDevice>("sdl", std::make_shared<SDLButtonFactory>());
RegisterFactory<AnalogDevice>("sdl", std::make_shared<SDLAnalogFactory>());
initialized = true;
}
}
void Shutdown() {
if (initialized) {
using namespace Input;
UnregisterFactory<ButtonDevice>("sdl");
UnregisterFactory<AnalogDevice>("sdl");
SDL_QuitSubSystem(SDL_INIT_JOYSTICK);
}
}
} // namespace SDL
} // namespace InputCommon
