mirror of
https://github.com/TomHarte/CLK.git
synced 2024-11-26 23:52:26 +00:00
108 lines
3.2 KiB
C++
108 lines
3.2 KiB
C++
//
|
|
// Joystick.hpp
|
|
// Clock Signal
|
|
//
|
|
// Created by Thomas Harte on 16/02/2021.
|
|
// Copyright © 2021 Thomas Harte. All rights reserved.
|
|
//
|
|
|
|
#pragma once
|
|
|
|
#include "../../../Inputs/Joystick.hpp"
|
|
|
|
#include <memory>
|
|
#include <vector>
|
|
|
|
namespace Apple::II {
|
|
|
|
class JoystickPair {
|
|
public:
|
|
JoystickPair() {
|
|
// Add a couple of joysticks.
|
|
joysticks_.emplace_back(new Joystick);
|
|
joysticks_.emplace_back(new Joystick);
|
|
}
|
|
|
|
class Joystick: public Inputs::ConcreteJoystick {
|
|
public:
|
|
Joystick() :
|
|
ConcreteJoystick({
|
|
Input(Input::Horizontal),
|
|
Input(Input::Vertical),
|
|
|
|
// The Apple II offers three buttons between two joysticks;
|
|
// this emulator puts three buttons on each joystick and
|
|
// combines them.
|
|
Input(Input::Fire, 0),
|
|
Input(Input::Fire, 1),
|
|
Input(Input::Fire, 2),
|
|
}) {}
|
|
|
|
void did_set_input(const Input &input, float value) final {
|
|
if(!input.info.control.index && (input.type == Input::Type::Horizontal || input.type == Input::Type::Vertical))
|
|
axes[(input.type == Input::Type::Horizontal) ? 0 : 1] = 1.0f - value;
|
|
}
|
|
|
|
void did_set_input(const Input &input, bool value) final {
|
|
if(input.type == Input::Type::Fire && input.info.control.index < 3) {
|
|
buttons[input.info.control.index] = value;
|
|
}
|
|
}
|
|
|
|
bool buttons[3] = {false, false, false};
|
|
float axes[2] = {0.5f, 0.5f};
|
|
};
|
|
|
|
inline bool button(size_t index) {
|
|
return joystick(0)->buttons[index] || joystick(1)->buttons[2-index];
|
|
}
|
|
|
|
inline bool analogue_channel_is_discharged(size_t channel) {
|
|
return (1.0f - static_cast<Joystick *>(joysticks_[channel >> 1].get())->axes[channel & 1]) < analogue_charge_ + analogue_biases_[channel];
|
|
}
|
|
|
|
inline void update_charge(float one_mhz_cycles = 1.0f) {
|
|
analogue_charge_ = std::min(analogue_charge_ + one_mhz_cycles * (1.0f / 2820.0f), 1.1f);
|
|
}
|
|
|
|
inline void access_c070() {
|
|
// Permit analogue inputs that are currently discharged to begin a charge cycle.
|
|
// Ensure those that were still charging retain that state.
|
|
for(size_t c = 0; c < 4; ++c) {
|
|
if(analogue_channel_is_discharged(c)) {
|
|
analogue_biases_[c] = 0.0f;
|
|
} else {
|
|
analogue_biases_[c] += analogue_charge_;
|
|
}
|
|
}
|
|
analogue_charge_ = 0.0f;
|
|
}
|
|
|
|
const std::vector<std::unique_ptr<Inputs::Joystick>> &get_joysticks() {
|
|
return joysticks_;
|
|
}
|
|
|
|
private:
|
|
// On an Apple II, the programmer strobes 0xc070 and that causes each analogue input
|
|
// to begin a charge and discharge cycle **if they are not already charging**.
|
|
// The greater the analogue input, the faster they will charge and therefore the sooner
|
|
// they will discharge.
|
|
//
|
|
// This emulator models that with analogue_charge_ being essentially the amount of time,
|
|
// in charge threshold units, since 0xc070 was last strobed. But if any of the analogue
|
|
// inputs were already partially charged then they gain a bias in analogue_biases_.
|
|
//
|
|
// It's a little indirect, but it means only having to increment the one value in the
|
|
// main loop.
|
|
float analogue_charge_ = 0.0f;
|
|
float analogue_biases_[4] = {0.0f, 0.0f, 0.0f, 0.0f};
|
|
|
|
std::vector<std::unique_ptr<Inputs::Joystick>> joysticks_;
|
|
|
|
inline Joystick *joystick(size_t index) {
|
|
return static_cast<Joystick *>(joysticks_[index].get());
|
|
}
|
|
};
|
|
|
|
}
|