Agregando sonido

src/CMakeLists.txt

@@ -7,6 +7,8 @@ target_sources(
         main.cpp
         Machine.cpp
         Machine.h
+        Sound.cpp
+        Sound.h
         Graphics/Graphics.cpp
         Graphics/Graphics.h
         Graphics/Color.h

src/Graphics/Graphics.cpp

@@ -18,7 +18,7 @@ void Graphics::create_sdl()
 {
     SDL_SetAppMetadata("CHIP-8 Emulator", "0.0.1", "fun.skrd.chip8");
 
-    if (!SDL_Init(SDL_INIT_VIDEO))
+    if (!SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO))
     {
         throw std::runtime_error(std::format("Couldn't initialize SDL: {}", SDL_GetError()));
     }

src/Interpreter/Interpreter.cpp

@@ -8,6 +8,7 @@ Interpreter::Interpreter(std::shared_ptr<MachineState> machine_state) :
     random_generator{std::random_device{}()}
 {
     srand(time(nullptr));
+    // quirks = static_cast<uint8_t>(InterpreterQuirks::COSMAC_STORE_AND_LOAD);
     for (bool& display : this->machine_state->display)
     {
         display = rand() % 100 > 50;
@@ -333,7 +334,8 @@ void Interpreter::ld_vx_byte(const Instruction& instruction) const
 
 void Interpreter::add_vx_byte(const Instruction& instruction) const
 {
-    this->machine_state->v[instruction.x] += instruction.kk;
+    auto& vx = this->machine_state->v[instruction.x];
+    vx = (vx + instruction.kk) & 0xFF;
 }
 
 void Interpreter::ld_vx_vy(const Instruction& instruction) const
@@ -344,16 +346,19 @@ void Interpreter::ld_vx_vy(const Instruction& instruction) const
 void Interpreter::or_vx_vy(const Instruction& instruction) const
 {
     this->machine_state->v[instruction.x] |= this->machine_state->v[instruction.y];
+    this->machine_state->v[0xF] = 0;
 }
 
 void Interpreter::and_vx_vy(const Instruction& instruction) const
 {
     this->machine_state->v[instruction.x] &= this->machine_state->v[instruction.y];
+    this->machine_state->v[0xF] = 0;
 }
 
 void Interpreter::xor_vx_vy(const Instruction& instruction) const
 {
     this->machine_state->v[instruction.x] ^= this->machine_state->v[instruction.y];
+    this->machine_state->v[0xF] = 0;
 }
 
 void Interpreter::add_vx_vy(const Instruction& instruction) const
@@ -362,16 +367,9 @@ void Interpreter::add_vx_vy(const Instruction& instruction) const
     const auto& vy = this->machine_state->v[instruction.y];
     auto& vf = this->machine_state->v[0xF];
 
-    if (vx + vy > 0xFF)
-    {
-        vf = 1;
-    }
-    else
-    {
-        vf = 0;
-    }
-
-    vx += vy;
+    const bool carry = vx + vy > 0x100;
+    vx = (vx + vy) & 0xFF;
+    vf = carry ? 1 : 0;
 }
 
 void Interpreter::sub_vx_vy(const Instruction& instruction) const
@@ -380,16 +378,9 @@ void Interpreter::sub_vx_vy(const Instruction& instruction) const
     const auto& vy = this->machine_state->v[instruction.y];
     auto& vf = this->machine_state->v[0xF];
 
-    if (vx > vy)
-    {
-        vf = 1;
-    }
-    else
-    {
-        vf = 0;
-    }
-
-    vx -= vy;
+    const bool carry = vx >= vy;
+    vx = (vx - vy) & 0xFF;
+    vf = carry ? 1 : 0;
 }
 
 void Interpreter::shr_vx_vy(const Instruction& instruction) const
@@ -403,16 +394,9 @@ void Interpreter::shr_vx_vy(const Instruction& instruction) const
         vx = vy;
     }
 
-    if (vx & 0x01)
-    {
-        vf = 1;
-    }
-    else
-    {
-        vf = 0;
-    }
-
+    const bool carry = vx & 0x01;
     vx = vx >> 1;
+    vf = carry ? 1 : 0;
 }
 
 void Interpreter::subn_vx_vy(const Instruction& instruction) const
@@ -421,16 +405,9 @@ void Interpreter::subn_vx_vy(const Instruction& instruction) const
     const auto& vy = this->machine_state->v[instruction.y];
     auto& vf = this->machine_state->v[0xF];
 
-    if (vy > vx)
-    {
-        vf = 1;
-    }
-    else
-    {
-        vf = 0;
-    }
-
-    vx = vy - vx;
+    const bool carry = vy >= vx;
+    vx = (vy - vx) & 0xFF;
+    vf = carry ? 1 : 0;
 }
 
 void Interpreter::shl_vx_vy(const Instruction& instruction) const
@@ -444,16 +421,9 @@ void Interpreter::shl_vx_vy(const Instruction& instruction) const
         vx = vy;
     }
 
-    if (vx & 0x80)
-    {
-        vf = 1;
-    }
-    else
-    {
-        vf = 0;
-    }
-
-    vx = vx << 1;
+    const bool carry = vx & 0x80;
+    vx = vx << 1 & 0xFF;
+    vf = carry ? 1 : 0;
 }
 
 void Interpreter::sne_vx_vy(const Instruction& instruction) const
@@ -502,6 +472,7 @@ void Interpreter::drw_vx_vy_nibble(const Instruction& instruction) const
     const uint8_t start_y = vy & 31;
     vf = 0;
 
+    bool carry = false;
     for (auto row = 0; row < instruction.n; row++)
     {
         const auto current_y = start_y + row;
@@ -530,7 +501,7 @@ void Interpreter::drw_vx_vy_nibble(const Instruction& instruction) const
                 if (display[index])
                 {
                     display[index] = false;
-                    vf = 1;
+                    carry = true;
                 }
                 else
                 {
@@ -539,11 +510,13 @@ void Interpreter::drw_vx_vy_nibble(const Instruction& instruction) const
             }
         }
     }
+
+    vf = carry ? 1 : 0;
 }
 
 void Interpreter::skp_vx(const Instruction& instruction) const
 {
-    if (this->machine_state->keyboard & 1 << instruction.x)
+    if (this->machine_state->keyboard & 1 << this->machine_state->v[instruction.x])
     {
         this->machine_state->pc += 2;
     }
@@ -551,7 +524,7 @@ void Interpreter::skp_vx(const Instruction& instruction) const
 
 void Interpreter::sknp_vx(const Instruction& instruction) const
 {
-    if (!(this->machine_state->keyboard & 1 << instruction.x))
+    if (!(this->machine_state->keyboard & 1 << this->machine_state->v[instruction.x]))
     {
         this->machine_state->pc += 2;
     }
@@ -562,22 +535,39 @@ void Interpreter::ld_vx_dt(const Instruction& instruction) const
     this->machine_state->v[instruction.x] = this->machine_state->dt;
 }
 
-void Interpreter::ld_vx_k(const Instruction& instruction) const
+void Interpreter::ld_vx_k(const Instruction& instruction)
 {
-    if (this->machine_state->keyboard == 0)
+    if (this->machine_state->keyboard == 0 && this->wait_for_key_released == 0)
     {
         this->machine_state->pc -= 2;
         return;
     }
 
-    for (auto key = 0; key < 16; key++)
+    if (this->machine_state->keyboard != 0 && this->wait_for_key_released == 0)
     {
-        if (this->machine_state->keyboard & 1 << key)
+        this->wait_for_key_released = this->machine_state->keyboard;
+        this->machine_state->pc -= 2;
+        return;
+    }
+
+    if (this->wait_for_key_released != 0)
+    {
+        const auto released_keys = this->wait_for_key_released & (~this->machine_state->keyboard);
+        if (released_keys != 0)
         {
-            this->machine_state->v[instruction.x] = key;
-            break;
+            for (auto key = 0; key < 16; key++)
+            {
+                if (released_keys & 1 << key)
+                {
+                    this->machine_state->v[instruction.x] = key;
+                    this->wait_for_key_released = 0;
+                    return;
+                }
+            }
         }
     }
+
+    this->machine_state->pc -= 2;
 }
 
 void Interpreter::ld_dt_vx(const Instruction& instruction) const

src/Interpreter/Interpreter.h

@@ -20,6 +20,7 @@ class Interpreter
     std::mt19937 random_generator;
 
     uint8_t quirks = 0;
+    uint16_t wait_for_key_released = false;
 
     void execute_instruction(const Instruction& instruction);
 
@@ -51,7 +52,7 @@ class Interpreter
     void skp_vx(const Instruction& instruction) const;
     void sknp_vx(const Instruction& instruction) const;
     void ld_vx_dt(const Instruction& instruction) const;
-    void ld_vx_k(const Instruction& instruction) const;
+    void ld_vx_k(const Instruction& instruction);
     void ld_dt_vx(const Instruction& instruction) const;
     void ld_st_vx(const Instruction& instruction) const;
     void add_i_vx(const Instruction& instruction) const;

src/Machine.cpp

@@ -16,6 +16,7 @@
 Machine::Machine() :
     machine_state{std::make_shared<MachineState>()},
     graphics{std::make_shared<Graphics>()},
+    sound{std::make_unique<Sound>()},
     callback_manager(std::make_shared<CallbackManager>()),
 
     interpreter{std::make_shared<Interpreter>(this->machine_state)},
@@ -26,6 +27,9 @@ Machine::Machine() :
     last_update_time{0},
     accumulator{0},
     target_cycle_time{1.0 / this->ips},
+    last_timer_time{0},
+    timer_accumulator{0},
+    timer_cycle_time{1.0 / 60},
     running{false}
 {
     this->register_callbacks();
@@ -36,9 +40,14 @@ void Machine::iterate()
 {
     if (running)
     {
+        this->update_timers();
         this->execute_interpreter();
     }
 
+    if (machine_state->st > 0)
+    {
+        this->sound->square();
+    }
     this->graphics->start();
     this->ui_manager->render();
     this->graphics->end();
@@ -52,6 +61,94 @@ bool Machine::on_event(const SDL_Event* event) const
     {
         return false;
     }
+    if (event->type == SDL_EVENT_KEY_DOWN || event->type == SDL_EVENT_KEY_UP)
+    {
+        const bool pressed = event->type == SDL_EVENT_KEY_DOWN;
+        switch (event->key.scancode)
+        {
+        case SDL_SCANCODE_1:
+            machine_state->keyboard = pressed
+                                          ? machine_state->keyboard | (1 << 0x1)
+                                          : machine_state->keyboard & ~(1 << 0x1);
+            break;
+        case SDL_SCANCODE_2:
+            machine_state->keyboard = pressed
+                                          ? machine_state->keyboard | (1 << 0x2)
+                                          : machine_state->keyboard & ~(1 << 0x2);
+            break;
+        case SDL_SCANCODE_3:
+            machine_state->keyboard = pressed
+                                          ? machine_state->keyboard | (1 << 0x3)
+                                          : machine_state->keyboard & ~(1 << 0x3);
+            break;
+        case SDL_SCANCODE_4:
+            machine_state->keyboard = pressed
+                                          ? machine_state->keyboard | (1 << 0xC)
+                                          : machine_state->keyboard & ~(1 << 0xC);
+            break;
+        case SDL_SCANCODE_Q:
+            machine_state->keyboard = pressed
+                                          ? machine_state->keyboard | (1 << 0x4)
+                                          : machine_state->keyboard & ~(1 << 0x4);
+            break;
+        case SDL_SCANCODE_W:
+            machine_state->keyboard = pressed
+                                          ? machine_state->keyboard | (1 << 0x5)
+                                          : machine_state->keyboard & ~(1 << 0x5);
+            break;
+        case SDL_SCANCODE_E:
+            machine_state->keyboard = pressed
+                                          ? machine_state->keyboard | (1 << 0x6)
+                                          : machine_state->keyboard & ~(1 << 0x6);
+            break;
+        case SDL_SCANCODE_R:
+            machine_state->keyboard = pressed
+                                          ? machine_state->keyboard | (1 << 0xD)
+                                          : machine_state->keyboard & ~(1 << 0xD);
+            break;
+        case SDL_SCANCODE_A:
+            machine_state->keyboard = pressed
+                                          ? machine_state->keyboard | (1 << 0x7)
+                                          : machine_state->keyboard & ~(1 << 0x7);
+            break;
+        case SDL_SCANCODE_S:
+            machine_state->keyboard = pressed
+                                          ? machine_state->keyboard | (1 << 0x8)
+                                          : machine_state->keyboard & ~(1 << 0x8);
+            break;
+        case SDL_SCANCODE_D:
+            machine_state->keyboard = pressed
+                                          ? machine_state->keyboard | (1 << 0x9)
+                                          : machine_state->keyboard & ~(1 << 0x9);
+            break;
+        case SDL_SCANCODE_F:
+            machine_state->keyboard = pressed
+                                          ? machine_state->keyboard | (1 << 0xE)
+                                          : machine_state->keyboard & ~(1 << 0xE);
+            break;
+        case SDL_SCANCODE_Z:
+            machine_state->keyboard = pressed
+                                          ? machine_state->keyboard | (1 << 0xA)
+                                          : machine_state->keyboard & ~(1 << 0xA);
+            break;
+        case SDL_SCANCODE_X:
+            machine_state->keyboard = pressed
+                                          ? machine_state->keyboard | (1 << 0x0)
+                                          : machine_state->keyboard & ~(1 << 0x0);
+            break;
+        case SDL_SCANCODE_C:
+            machine_state->keyboard = pressed
+                                          ? machine_state->keyboard | (1 << 0xB)
+                                          : machine_state->keyboard & ~(1 << 0xB);
+            break;
+        case SDL_SCANCODE_V:
+            machine_state->keyboard = pressed
+                                          ? machine_state->keyboard | (1 << 0xF)
+                                          : machine_state->keyboard & ~(1 << 0xF);
+            break;
+        default: break;
+        }
+    }
 
     return true;
 }
@@ -70,6 +167,21 @@ void Machine::execute_interpreter()
     }
 }
 
+void Machine::update_timers()
+{
+    const auto current_time = SDL_GetTicks();
+    const auto delta_time = static_cast<double>(current_time - this->last_update_time) / 1000.0;
+    this->last_timer_time = current_time;
+    this->timer_accumulator += delta_time;
+
+    while (this->timer_accumulator >= this->timer_cycle_time)
+    {
+        machine_state->dt = machine_state->dt > 0 ? machine_state->dt - 1 : 0;
+        machine_state->st = machine_state->st > 0 ? machine_state->st - 1 : 0;
+        this->timer_accumulator -= this->timer_cycle_time;
+    }
+}
+
 void Machine::register_callbacks()
 {
     callback_manager->rom_load_callback.push_back(std::bind(

src/Machine.h

@@ -1,6 +1,7 @@
 #ifndef MACHINE_H
 #define MACHINE_H
 
+#include "Sound.h"
 #include "Graphics/Graphics.h"
 #include "Interpreter/Interpreter.h"
 #include "SDL3/SDL_events.h"
@@ -11,6 +12,7 @@ class Machine
 {
     std::shared_ptr<MachineState> machine_state;
     std::shared_ptr<Graphics> graphics;
+    std::unique_ptr<Sound> sound;
     std::shared_ptr<CallbackManager> callback_manager;
 
     std::shared_ptr<Interpreter> interpreter;
@@ -21,10 +23,16 @@ class Machine
     double accumulator;
     double target_cycle_time;
 
+    uint64_t last_timer_time;
+    double timer_accumulator;
+    double timer_cycle_time;
+
     std::string rom;
     bool running;
 
     void execute_interpreter();
+    void update_timers();
+
     void on_rom_load(const std::string& path);
     void on_reset() const;
     void on_stop();

src/Sound.cpp

@@ -0,0 +1,88 @@
+#include "Sound.h"
+
+#include <format>
+
+#include "SDL3/SDL.h"
+
+void SDLAudioStreamDestroyer::operator()(SDL_AudioStream* stream) const
+{
+    SDL_DestroyAudioStream(stream);
+}
+
+Sound::Sound()
+{
+    spec.channels = 1;
+    spec.format = SDL_AUDIO_F32;
+    spec.freq = 8000;
+
+    SDL_AudioStream* raw_stream = SDL_OpenAudioDeviceStream(SDL_AUDIO_DEVICE_DEFAULT_PLAYBACK, &spec, nullptr, nullptr);
+    if (!raw_stream)
+    {
+        throw std::runtime_error(std::format("Couldn't initialize audio stream: {}", SDL_GetError()));
+    }
+
+    stream = std::unique_ptr<SDL_AudioStream, SDLAudioStreamDestroyer>(raw_stream);
+
+
+    SDL_ResumeAudioStreamDevice(stream.get());
+}
+
+void Sound::sine()
+{
+    constexpr int minimum_audio = (8000 * sizeof(float)) / 6;
+    constexpr int freq = 440;
+
+    if (SDL_GetAudioStreamQueued(stream.get()) < minimum_audio)
+    {
+        static float samples[512];
+        for (std::size_t i = 0; i < std::size(samples); i++)
+        {
+            const float phase = current_sine_sample * freq / 8000.0f;
+            samples[i] = SDL_sinf(phase * 2 * SDL_PI_F);
+            current_sine_sample++;
+        }
+
+        current_sine_sample %= 8000;
+
+        SDL_PutAudioStreamData(stream.get(), samples, sizeof (samples));
+    }
+}
+
+void Sound::noise()
+{
+    constexpr int minimum_audio = (8000 * sizeof(float)) / 6;
+    constexpr int freq = 440;
+    if (SDL_GetAudioStreamQueued(stream.get()) < minimum_audio)
+    {
+        static float samples[512];
+
+        for (std::size_t i = 0; i < std::size(samples); i++)
+        {
+            samples[i] = SDL_rand(2) * freq;
+        }
+
+        SDL_PutAudioStreamData(stream.get(), samples, sizeof (samples));
+    }
+}
+
+void Sound::square()
+{
+    constexpr int minimum_audio = (8000 * sizeof(float)) / 6;
+    constexpr int freq = 440;
+    constexpr float amplitude = 0.5f;
+
+    if (SDL_GetAudioStreamQueued(stream.get()) < minimum_audio)
+    {
+        static float samples[512];
+        for (std::size_t i = 0; i < std::size(samples); i++)
+        {
+            const float phase = current_sine_sample * freq / 8000.0f;
+            samples[i] = (SDL_sinf(phase * 2 * SDL_PI_F) >= 0.0f) ? amplitude : -amplitude;
+            current_sine_sample++;
+        }
+
+        current_sine_sample %= 8000;
+
+        SDL_PutAudioStreamData(stream.get(), samples, sizeof(samples));
+    }
+}

src/Sound.h

@@ -0,0 +1,28 @@
+#ifndef SOUND_H
+#define SOUND_H
+#include <memory>
+#include <SDL3/SDL.h>
+
+
+struct SDLAudioStreamDestroyer
+{
+    void operator()(SDL_AudioStream* stream) const;
+};
+
+class Sound
+{
+    SDL_AudioSpec spec;
+    std::unique_ptr<SDL_AudioStream, SDLAudioStreamDestroyer> stream;
+
+    int current_sine_sample = 0;
+
+public:
+    Sound();
+
+    void sine();
+    void noise();
+    void square();
+};
+
+
+#endif //SOUND_H

src/UI/RegisterView.cpp

@@ -52,6 +52,8 @@ void RegisterView::render()
             }
         }
         ImGui::EndTable();
+
+        ImGui::Text("Keyboard: 0b%016B", this->machine_state->keyboard);
     }
     ImGui::End();
 }