ImGui backend for OOGL (https://github.com/Overv/OOGL)

imguiImpl.cpp

#include <imgui.h>
#include <GL/OOGL.hpp>
#include <backends/imgui_impl_opengl3.h>
#include <unordered_map>

// clang-format off
const std::unordered_map<GL::Key::key_t, ImGuiKey> keymap = {
  {GL::Key::F1, ImGuiKey_F1}, {GL::Key::F2, ImGuiKey_F2}, {GL::Key::F3, ImGuiKey_F3}, {GL::Key::F4, ImGuiKey_F4}, {GL::Key::F5, ImGuiKey_F5}, {GL::Key::F6, ImGuiKey_F6},
  {GL::Key::F7, ImGuiKey_F7}, {GL::Key::F8, ImGuiKey_F8}, {GL::Key::F9, ImGuiKey_F9}, {GL::Key::F10, ImGuiKey_F10}, {GL::Key::F11, ImGuiKey_F11}, {GL::Key::F12, ImGuiKey_F12},

  {GL::Key::A, ImGuiKey_A}, {GL::Key::B, ImGuiKey_B}, {GL::Key::C, ImGuiKey_C}, {GL::Key::D, ImGuiKey_D}, {GL::Key::E, ImGuiKey_E}, {GL::Key::F, ImGuiKey_F}, {GL::Key::G, ImGuiKey_G},
  {GL::Key::H, ImGuiKey_H}, {GL::Key::I, ImGuiKey_I}, {GL::Key::J, ImGuiKey_J}, {GL::Key::K, ImGuiKey_K}, {GL::Key::L, ImGuiKey_L}, {GL::Key::M, ImGuiKey_M}, {GL::Key::N, ImGuiKey_N},
  {GL::Key::O, ImGuiKey_O}, {GL::Key::P, ImGuiKey_P}, {GL::Key::Q, ImGuiKey_Q}, {GL::Key::R, ImGuiKey_R}, {GL::Key::S, ImGuiKey_S}, {GL::Key::T, ImGuiKey_T}, {GL::Key::U, ImGuiKey_U},
  {GL::Key::V, ImGuiKey_V}, {GL::Key::W, ImGuiKey_W}, {GL::Key::X, ImGuiKey_X}, {GL::Key::Y, ImGuiKey_Y}, {GL::Key::Z, ImGuiKey_Z},

  {GL::Key::Num0, ImGuiKey_0}, {GL::Key::Num1, ImGuiKey_1}, {GL::Key::Num2, ImGuiKey_2}, {GL::Key::Num3, ImGuiKey_3}, {GL::Key::Num4, ImGuiKey_4},
  {GL::Key::Num5, ImGuiKey_5}, {GL::Key::Num6, ImGuiKey_6}, {GL::Key::Num7, ImGuiKey_7}, {GL::Key::Num8, ImGuiKey_8}, {GL::Key::Num9, ImGuiKey_9},

  {GL::Key::LeftBracket, ImGuiKey_LeftBracket}, {GL::Key::RightBracket, ImGuiKey_RightBracket}, {GL::Key::Semicolon, ImGuiKey_Semicolon}, {GL::Key::Comma, ImGuiKey_Comma},
  {GL::Key::Period, ImGuiKey_Period}, {GL::Key::Quote, ImGuiKey_Apostrophe}, {GL::Key::Slash, ImGuiKey_Slash}, {GL::Key::Backslash, ImGuiKey_Backslash},
  {GL::Key::Tilde, ImGuiKey_GraveAccent}, {GL::Key::Equals, ImGuiKey_Equal}, {GL::Key::Hyphen, ImGuiKey_Minus}, {GL::Key::Escape, ImGuiKey_Escape},
  {GL::Key::Control, ImGuiKey_ModCtrl}, {GL::Key::Shift, ImGuiKey_ModShift}, {GL::Key::Alt, ImGuiKey_ModAlt}, {GL::Key::Space, ImGuiKey_Space},
  {GL::Key::Enter, ImGuiKey_Enter}, {GL::Key::Backspace, ImGuiKey_Backspace}, {GL::Key::Tab, ImGuiKey_Tab}, {GL::Key::PageUp, ImGuiKey_PageUp},
  {GL::Key::PageDown, ImGuiKey_PageDown}, {GL::Key::End, ImGuiKey_End}, {GL::Key::Home, ImGuiKey_Home}, {GL::Key::Insert, ImGuiKey_Insert},
  {GL::Key::Delete, ImGuiKey_Delete}, {GL::Key::Pause, ImGuiKey_Pause},

  {GL::Key::Left, ImGuiKey_LeftArrow}, {GL::Key::Right, ImGuiKey_RightArrow}, {GL::Key::Up, ImGuiKey_UpArrow}, {GL::Key::Down, ImGuiKey_DownArrow},
  {GL::Key::Numpad0, ImGuiKey_Keypad0}, {GL::Key::Numpad1, ImGuiKey_Keypad1}, {GL::Key::Numpad2, ImGuiKey_Keypad2}, {GL::Key::Numpad3, ImGuiKey_Keypad3}, {GL::Key::Numpad4, ImGuiKey_Keypad4},
  {GL::Key::Numpad5, ImGuiKey_Keypad5}, {GL::Key::Numpad6, ImGuiKey_Keypad6}, {GL::Key::Numpad7, ImGuiKey_Keypad7}, {GL::Key::Numpad8, ImGuiKey_Keypad8}, {GL::Key::Numpad9, ImGuiKey_Keypad9},
  {GL::Key::Divide, ImGuiKey_KeypadDivide}, {GL::Key::Multiply, ImGuiKey_KeypadMultiply}, {GL::Key::Subtract, ImGuiKey_KeypadSubtract}, {GL::Key::Add, ImGuiKey_KeypadAdd},
  {GL::Key::Unknown, ImGuiKey_None},
};
// clang-format on

void ImGuiOOGL_Init(GL::Window& window) {
  ImGui::CreateContext();
  ImGuiIO& io = ImGui::GetIO();
  io.BackendFlags |= ImGuiBackendFlags_HasMouseCursors;
  io.BackendFlags |= ImGuiBackendFlags_HasSetMousePos;

  ImGui_ImplOpenGL3_Init("#version 330 core");
  io.BackendPlatformUserData = (void*)&window.GetContext();
  io.BackendPlatformName = "imgui_impl_mova";

  ImGuiViewport* main_viewport = ImGui::GetMainViewport();
  main_viewport->PlatformHandle = (void*)&window;
}

void ImGuiOOGL_NewFrame() {
  static float lastTime = 0;
  ImGuiIO& io = ImGui::GetIO();
  float time = ((GL::Context*)io.BackendPlatformUserData)->Time();
  GL::Window* window = (GL::Window*)ImGui::GetMainViewport()->PlatformHandle;
  io.DisplaySize = ImVec2(window->GetWidth(), window->GetHeight());
  io.DeltaTime = std::max(time - lastTime, 0.001f);
  lastTime = time;
  ImGui_ImplOpenGL3_NewFrame();
  ImGui::NewFrame();
}

void ImGuiOOGL_AddEvent(GL::Event& event) {
  ImGuiIO& io = ImGui::GetIO();
  if (event.Type == GL::Event::MouseDown || event.Type == GL::Event::MouseUp) {
    if (event.Mouse.Button == GL::MouseButton::Left) {
      io.AddMouseButtonEvent(ImGuiMouseButton_Left, event.Type == GL::Event::MouseDown);
    } else if (event.Mouse.Button == GL::MouseButton::Middle) {
      io.AddMouseButtonEvent(ImGuiMouseButton_Middle, event.Type == GL::Event::MouseDown);
    } else if (event.Mouse.Button == GL::MouseButton::Right) {
      io.AddMouseButtonEvent(ImGuiMouseButton_Right, event.Type == GL::Event::MouseDown);
    }
  } else if (event.Type == GL::Event::MouseMove) {
    io.AddMousePosEvent(event.Mouse.X, event.Mouse.Y);
  } else if (event.Type == GL::Event::MouseWheel) {
    io.AddMouseWheelEvent(0, event.Mouse.Delta);
  } else if (event.Type == GL::Event::KeyDown || event.Type == GL::Event::KeyUp) {
    io.AddKeyEvent(keymap.at(event.Key.Code), event.Type == GL::Event::KeyDown);
    io.AddKeyEvent(ImGuiKey_ModCtrl, event.Key.Control);
    io.AddKeyEvent(ImGuiKey_ModShift, event.Key.Shift);
    io.AddKeyEvent(ImGuiKey_ModAlt, event.Key.Alt);
    // io.AddInputCharacter(character);
  }
}

void ImGuiOOGL_Render() {
  ImGui::Render();
  ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
}

void ImGuiOOGL_Shutdown() {
  ImGui_ImplOpenGL3_Shutdown();
  ImGui::DestroyContext();
}

imguiImpl.h

#include <imgui.h>
#include <GL/OOGL.hpp>

void ImGuiOOGL_Init(GL::Window& window);
void ImGuiOOGL_NewFrame();
void ImGuiOOGL_AddEvent(GL::Event& event);
void ImGuiOOGL_Render();
void ImGuiOOGL_Shutdown();