sid register explorer

sidexplore.cpp

#include <cstdio>
#include <thread>
#include <set>
#include <string>

#include <GLFW/glfw3.h>

#include "imgui.h"
#include "backends/imgui_impl_glfw.h"
#include "backends/imgui_impl_opengl2.h"


static uint8_t reg_ext[32];
static uint8_t reg_int[32];

int  voice_freq [3];
int  voice_pw   [3];

bool voice_noise[3];
bool voice_pulse[3];
bool voice_saw  [3];
bool voice_tri  [3];

bool voice_test [3];
bool voice_ring [3];
bool voice_sync [3];
bool voice_gate [3];

int  voice_atk  [3];
int  voice_dcy  [3];
int  voice_sus  [3];
int  voice_rel  [3];

int  filter_freq;
int  filter_res;
bool filter_ext;
bool filter_voice3;
bool filter_voice2;
bool filter_voice1;
bool filter_3off;
bool filter_hp;
bool filter_bp;
bool filter_lp;
int  master_volume;

static void sid_voice(uint32_t num) {
  std::string windowName = std::string("SidVoice #") + std::to_string(num + 1);
  ImGui::Begin(windowName.c_str());

  ImGui::SliderInt("FREQ", &voice_freq[num], 0, 0xffff, "%d");
  ImGui::SliderInt("PW",   &voice_pw  [num], 0, 0xfff,  "%d");

  ImGui::Checkbox("NOISE", &voice_noise[num]);
  ImGui::Checkbox("PULSE", &voice_pulse[num]);
  ImGui::Checkbox("SAW",   &voice_saw  [num]);
  ImGui::Checkbox("TRI",   &voice_tri  [num]);

  ImGui::Checkbox("TEST", &voice_test [num]);
  ImGui::Checkbox("RING", &voice_ring [num]);
  ImGui::Checkbox("SYNC", &voice_sync [num]);
  ImGui::Checkbox("GATE", &voice_gate [num]);

  ImGui::SliderInt("ATK",  &voice_atk [num], 0, 0xf,    "%d");
  ImGui::SliderInt("DCY",  &voice_dcy [num], 0, 0xf,    "%d");
  ImGui::SliderInt("SUS",  &voice_sus [num], 0, 0xf,    "%d");
  ImGui::SliderInt("REL",  &voice_rel [num], 0, 0xf,    "%d");

  ImGui::End();
}

static void sid_filter() {
  ImGui::Begin("Filter");
  ImGui::SliderInt("CUTOFF", &filter_freq,   0, 0x3ff);
  ImGui::SliderInt("RES",    &filter_res,    0, 0xf);

  ImGui::Checkbox("EXT",     &filter_ext);
  ImGui::Checkbox("VOICE 3", &filter_voice3);
  ImGui::Checkbox("VOICE 2", &filter_voice2);
  ImGui::Checkbox("VOICE 1", &filter_voice1);

  ImGui::Checkbox("3OFF",    &filter_3off);
  ImGui::Checkbox("HP",      &filter_hp);
  ImGui::Checkbox("BP",      &filter_bp);
  ImGui::Checkbox("LP",      &filter_lp);

  ImGui::SliderInt("VOLUME", &master_volume, 0, 0xf);
  ImGui::End();
}

static void make_int_regs() {
  for (int i=0; i<3; ++i) {
    int base = (i == 2) ? 0xe : ((i == 1) ? 0x7 : 0x0);
    reg_int[base+0] = voice_freq[i]       & 0xff;
    reg_int[base+1] = voice_freq[i] >> 8;
    reg_int[base+2] = voice_pw  [i]       & 0xff;
    reg_int[base+3] =(voice_pw  [i] >> 8) & 0x0f;
    reg_int[base+4] =
      (voice_noise[i] ? 0x80 : 0) |
      (voice_pulse[i] ? 0x40 : 0) |
      (voice_saw  [i] ? 0x20 : 0) |
      (voice_tri  [i] ? 0x10 : 0) |
      (voice_test [i] ? 0x08 : 0) |
      (voice_ring [i] ? 0x04 : 0) |
      (voice_sync [i] ? 0x02 : 0) |
      (voice_gate [i] ? 0x01 : 0);
    reg_int[base+5] = ((voice_atk[i] & 0xf) << 4) | voice_dcy[i] & 0xf;
    reg_int[base+6] = ((voice_sus[i] & 0xf) << 4) | voice_rel[i] & 0xf;
  }
  reg_int[0x15] =  filter_freq       & 0x03;
  reg_int[0x16] = (filter_freq >> 3) & 0xff;
  reg_int[0x17] =
    ((filter_res << 4) & 0xf0) |
    (filter_ext    ? 0x08 : 0) |
    (filter_voice3 ? 0x04 : 0) |
    (filter_voice2 ? 0x02 : 0) |
    (filter_voice1 ? 0x01 : 0);
  reg_int[0x18] =
    (filter_3off   ? 0x80 : 0) |
    (filter_hp     ? 0x40 : 0) |
    (filter_bp     ? 0x20 : 0) |
    (filter_lp     ? 0x10 : 0) |
    (master_volume & 0x0f);
}

static void send_ext_regs() {
  for (int i = 0; i < 0x19; ++i) {
    if (reg_int[i] != reg_ext[i]) {
      reg_ext[i] = reg_int[i];

      // send register
    }
  }
}

static void glfw_error_callback(int error, const char* description) {
  fprintf(stderr, "Glfw Error %d: %s\n", error, description);
}

int main(int, char**) {

  // Setup window
  glfwSetErrorCallback(glfw_error_callback);
  if (!glfwInit())
      return 1;
  glfwWindowHint(GLFW_RESIZABLE, GLFW_TRUE);
  GLFWmonitor* monitor = 0 ? glfwGetPrimaryMonitor() : nullptr;
  GLFWwindow* window = glfwCreateWindow(1024, 768, "sidexplorer", monitor, nullptr);
  if (window == nullptr)
      return 1;
  glfwMakeContextCurrent(window);
  glfwSwapInterval(1);

  // Setup Dear ImGui context
  IMGUI_CHECKVERSION();
  ImGui::CreateContext();

  // Setup Dear ImGui style
  ImGui::StyleColorsDark();

  // Setup Platform/Renderer backends
  ImGui_ImplGlfw_InitForOpenGL(window, true);
  ImGui_ImplOpenGL2_Init();

  // Main loop
  while (!glfwWindowShouldClose(window)) {
    glfwPollEvents();

    // Start the Dear ImGui frame
    ImGui_ImplOpenGL2_NewFrame();
    ImGui_ImplGlfw_NewFrame();
    ImGui::NewFrame();

    sid_voice(0);
    sid_voice(1);
    sid_voice(2);
    sid_filter();

    // Rendering
    ImGui::Render();
    int display_w, display_h;
    glfwGetFramebufferSize(window, &display_w, &display_h);
    glViewport(0, 0, display_w, display_h);
    glClearColor(.1f, .2f, .4f, 1.f);
    glClear(GL_COLOR_BUFFER_BIT);

    ImGui_ImplOpenGL2_RenderDrawData(ImGui::GetDrawData());
    glfwMakeContextCurrent(window);
    glfwSwapBuffers(window);

    // update registers
    make_int_regs();
    send_ext_regs();

    // dont wipe out the CPU
    std::this_thread::yield();
  }

  // Cleanup
  ImGui_ImplOpenGL2_Shutdown();
  ImGui_ImplGlfw_Shutdown();
  ImGui::DestroyContext();
  glfwDestroyWindow(window);
  glfwTerminate();

  return 0;
}