main_gui.cpp

#include <GLFW/glfw3.h>
#include <imgui.h>
#include <imgui_impl_glfw.h>
#include <imgui_impl_opengl3.h>
#include <iostream>
#include <fmt/core.h>
#include <thread>
#include "renderer.hpp"

static void glfw_error_callback(int error, const char* description)
{
    fmt::print(stderr, "Glfw Error {}: {}\n", error, description);
}

int main() {

    glfwSetErrorCallback(glfw_error_callback);

    if (!glfwInit())
        return 1;

    const char* glsl_version = "#version 130";
    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);

    const GLFWvidmode * mode = glfwGetVideoMode(glfwGetPrimaryMonitor());
    float resolution_x = mode->width;
    float resolution_y = mode->height;
    float scale = 0.5;

    GLFWwindow* window = glfwCreateWindow(resolution_x * scale, resolution_y * scale, "Ecosystem Simulation", NULL, NULL);
    if (window == NULL)
        return 1;
    glfwMakeContextCurrent(window);
    glfwSwapInterval(1); // Enable vsync

    IMGUI_CHECKVERSION();
    ImGui::CreateContext();
    ImGuiIO& io = ImGui::GetIO(); (void)io;
    //std::filesystem::path font_file = helper::ecosystem_root / "simulation" / "run" / "fonts" / "Open_Sans" / "static" / "OpenSans" / "OpenSans-Regular.ttf";
    io.Fonts->AddFontFromFileTTF("OpenSans-Regular.ttf", 18);
    io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;
    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;
    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;

    ImGui::StyleColorsDark();

    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
    ImGuiStyle& style = ImGui::GetStyle();
    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
    {
        style.WindowRounding = 0.0f;
        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
    }

    // Setup Platform/Renderer backends
    ImGui_ImplGlfw_InitForOpenGL(window, true);
    ImGui_ImplOpenGL3_Init(glsl_version);

    ImVec4 clear_color = ImVec4(0.45f, 0.55f, 0.60f, 1.00f);

    Renderer renderer;
    std::thread runner([&renderer](){renderer.run();});

    while (!glfwWindowShouldClose(window)) {
        glfwPollEvents();

        // Start the Dear ImGui frame
        ImGui_ImplOpenGL3_NewFrame();
        ImGui_ImplGlfw_NewFrame();
        ImGui::NewFrame();

        renderer.RenderUI();

        // Rendering
        ImGui::Render();
        int display_w, display_h;
        glfwGetFramebufferSize(window, &display_w, &display_h);
        glViewport(0, 0, display_w, display_h);
        glClearColor(clear_color.x * clear_color.w, clear_color.y * clear_color.w, clear_color.z * clear_color.w, clear_color.w);
        glClear(GL_COLOR_BUFFER_BIT);
        ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());

        // Update and Render additional Platform Windows
        // (Platform functions may change the current OpenGL context, so we save/restore it to make it easier to paste this code elsewhere.
        //  For this specific demo app we could also call glfwMakeContextCurrent(window) directly)
        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
        {
            GLFWwindow* backup_current_context = glfwGetCurrentContext();
            ImGui::UpdatePlatformWindows();
            ImGui::RenderPlatformWindowsDefault();
            glfwMakeContextCurrent(backup_current_context);
        }

        glfwSwapBuffers(window);
    }

    ImGui_ImplOpenGL3_Shutdown();
    ImGui_ImplGlfw_Shutdown();
    ImGui::DestroyContext();
    glfwDestroyWindow(window);
    glfwTerminate();
    if(renderer.state == State::TAKING_INPUT)
    {
        renderer.renderer_lock.unlock();
        renderer.cond.notify_one();
    }
    renderer.state = State::ABORT;
    runner.join();
    return 0;
}