main.cpp

// Include libs
#include "imgui.h"
#include "imgui_impl_glfw.h"
#include "imgui_impl_vulkan.h"
#include <cstdio>
#include <cstdlib>
#include <iostream>
#include <GLFW/glfw3.h>
#include <chrono>

#include "src/MainBar.h"
#include "src/Profiler.h"

#define GLFW_INCLUDE_NONE
#define GLFW_INCLUDE_VULKAN

#ifdef _DEBUG
#define APP_USE_VULKAN_DEBUG_REPORT
static VkDebugReportCallbackEXT g_DebugReport = VK_NULL_HANDLE;
#endif

// Select modes for unlimited fps
// If commented the code will stick to 60fps v-sync
// #define APP_USE_UNLIMITED_FRAME_RATE

// Data
static VkAllocationCallbacks*   g_Allocator = nullptr;
static VkInstance               g_Instance = VK_NULL_HANDLE;
static VkPhysicalDevice         g_PhysicalDevice = VK_NULL_HANDLE;
static VkDevice                 g_Device = VK_NULL_HANDLE;
static uint32_t                 g_QueueFamily = (uint32_t)-1;
static VkQueue                  g_Queue = VK_NULL_HANDLE;
static VkPipelineCache          g_PipelineCache = VK_NULL_HANDLE;
static VkDescriptorPool         g_DescriptorPool = VK_NULL_HANDLE;

static ImGui_ImplVulkanH_Window g_MainWindowData;
static uint32_t                 g_MinImageCount = 2;
static bool                     g_SwapChainRebuild = false;

static bool show_mainBar = false;

// Call instance of Profiler to get FPS
extern Profiler profiler;

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

static void check_vk_result(VkResult err)
{
    if (err == VK_SUCCESS)
    {
        return;
    }
    fprintf(stderr, "[vulkan] Error: VkResult = %d\n", err);
    if (err < 0)
    {
        abort();
    }
}

#ifdef APP_USE_VULKAN_DEBUG_REPORT
static VKAPI_ATTR VkBool32 VKAPI_CALL debug_report(VkDebugReportFlagsEXT flags, VkDebugReportObjectTypeEXT objectType, uint64_t object, size_t location, int32_t messageCode, const char* pLayerPrefix, const char* pMessage, void* pUserData)
{
    // Unused parameters
    (void) flags;
    (void) object;
    (void) location;
    (void) messageCode;
    (void) pUserData;
    (void) pLayerPrefix;
    // Debug print
    fprintf(stderr, "[vulkan] Debug report from ObjectType: %i\nMessage: %s \n\n", objectType, pMessage);
    return VK_FALSE;
}
#endif

static bool IsExtensionAvailable(const ImVector<VkExtensionProperties>& properties, const char* extension)
{
    for (const VkExtensionProperties& p : properties)
    {
        if (strcmp(p.extensionName, extension) == 0)
        {
            return true;
        }
    }
    return false;
}

// Setup of the Vulkan Window
static void SetupVulkan(ImVector<const char*> instance_extensions)
{
    VkResult err;

    // Create Vulkan Instance
    {
        VkInstanceCreateInfo create_Info = {};
        create_Info.sType = VK_STRUCTURE_TYPE_INSTANCE_CREATE_INFO;

        // Available extensions
        uint32_t properties_count;
        ImVector<VkExtensionProperties> properties;
        vkEnumerateInstanceExtensionProperties(nullptr, &properties_count, nullptr);
        properties.resize(properties_count);
        err = vkEnumerateInstanceExtensionProperties(nullptr, &properties_count, properties.Data);
        check_vk_result(err);

        // Enable required extensions
        if (IsExtensionAvailable(properties, VK_KHR_GET_PHYSICAL_DEVICE_PROPERTIES_2_EXTENSION_NAME))
            instance_extensions.push_back(VK_KHR_GET_PHYSICAL_DEVICE_PROPERTIES_2_EXTENSION_NAME);
#ifdef VK_KHR_PORTABILITY_ENUMERATION_EXTENSION_NAME
        if (IsExtensionAvailable(properties, VK_KHR_PORTABILITY_ENUMERATION_EXTENSION_NAME))
        {
            instance_extensions.push_back(VK_KHR_PORTABILITY_ENUMERATION_EXTENSION_NAME);
            create_Info.flags |= VK_INSTANCE_CREATE_ENUMERATE_PORTABILITY_BIT_KHR;
        }
#endif

        // Enable validation layers
#ifdef APP_USE_VULKAN_DEBUG_REPORT
        const char* layers[] = { "VK_LAYER_KHRONOS_validation" };
        create_Info.enabledLayerCount = 1;
        create_Info.ppEnabledLayerNames = layers;
        instance_extensions.push_back("VK_EXT_debug_report");
#endif

        // Create Vulkan Instance
        create_Info.enabledExtensionCount = (uint32_t) instance_extensions.Size;
        create_Info.ppEnabledExtensionNames = instance_extensions.Data;
        err = vkCreateInstance(&create_Info, g_Allocator, &g_Instance);
        check_vk_result(err);

        // Setup debug report callback
#ifdef APP_USE_VULKAN_DEBUG_REPORT
        auto f_vkCreateDebugReportCallbackEXT = (PFN_vkCreateDebugReportCallbackEXT)vkGetInstanceProcAddr(g_Instance, "vkCreateDebugReportCallbackEXT");
        IM_ASSERT(f_vkCreateDebugReportCallbackEXT != nullptr);
        VkDebugReportCallbackCreateInfoEXT debug_report_ci = {};
        debug_report_ci.sType = VK_STRUCTURE_TYPE_DEBUG_REPORT_CREATE_INFO_EXT;
        debug_report_ci.flags = VK_DEBUG_REPORT_ERROR_BIT_EXT | VK_DEBUG_REPORT_WARNING_BIT_EXT | VK_DEBUG_REPORT_PERFORMANCE_WARNING_BIT_EXT;
        debug_report_ci.pfnCallback = debug_report;
        debug_report_ci.pUserData = nullptr;
        err = f_vkCreateDebugReportCallbackEXT(g_Instance, &debug_report_ci, g_Allocator, &g_DebugReport);
        check_vk_result(err);
#endif
    }

    // Select Physical Device (GPU)
    g_PhysicalDevice = ImGui_ImplVulkanH_SelectPhysicalDevice(g_Instance);
    IM_ASSERT(g_PhysicalDevice != VK_NULL_HANDLE);

    // Select graphics queue family
    g_QueueFamily = ImGui_ImplVulkanH_SelectQueueFamilyIndex(g_PhysicalDevice);
    IM_ASSERT(g_QueueFamily != (uint32_t)-1);

    // Create Logical Device (1 queue)
    {
        ImVector<const char*> device_extensions;
        device_extensions.push_back("VK_KHR_swapchain");

        // Enumerate physical device extension
        uint32_t properties_count;
        ImVector<VkExtensionProperties> properties;
        vkEnumerateDeviceExtensionProperties(g_PhysicalDevice, nullptr, &properties_count, nullptr);
        properties.resize(properties_count);
        vkEnumerateDeviceExtensionProperties(g_PhysicalDevice, nullptr, &properties_count, properties.Data);
#ifdef VK_KHR_PORTABILITY_SUBSET_EXTENSION_NAME
        if (IsExtensionAvailable(properties, VK_KHR_PORTABILITY_SUBSET_EXTENSION_NAME))
        {
            device_extensions.push_back(VK_KHR_PORTABILITY_SUBSET_EXTENSION_NAME);
        }
#endif

        const float queue_priority[] = { 1.0f };
        VkDeviceQueueCreateInfo queue_info[1] = {};
        queue_info[0].sType = VK_STRUCTURE_TYPE_DEVICE_QUEUE_CREATE_INFO;
        queue_info[0].queueFamilyIndex = g_QueueFamily;
        queue_info[0].queueCount = 1;
        queue_info[0].pQueuePriorities = queue_priority;
        VkDeviceCreateInfo create_info = {};
        create_info.sType = VK_STRUCTURE_TYPE_DEVICE_CREATE_INFO;
        create_info.queueCreateInfoCount = sizeof(queue_info) / sizeof(queue_info[0]);
        create_info.pQueueCreateInfos = queue_info;
        create_info.enabledExtensionCount = (uint32_t)device_extensions.Size;
        create_info.ppEnabledExtensionNames = device_extensions.Data;
        err = vkCreateDevice(g_PhysicalDevice, &create_info, g_Allocator, &g_Device);
        check_vk_result(err);
        vkGetDeviceQueue(g_Device, g_QueueFamily, 0, &g_Queue);    }

    {
        VkDescriptorPoolSize pool_sizes[] =
        {
            { VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, IMGUI_IMPL_VULKAN_MINIMUM_IMAGE_SAMPLER_POOL_SIZE },
        };
        VkDescriptorPoolCreateInfo pool_info = {};
        pool_info.sType = VK_STRUCTURE_TYPE_DESCRIPTOR_POOL_CREATE_INFO;
        pool_info.maxSets = 1;
        for (VkDescriptorPoolSize& pool_size : pool_sizes)
        {
            pool_info.maxSets += pool_size.descriptorCount;
        }
        pool_info.poolSizeCount = (uint32_t) IM_ARRAYSIZE(pool_sizes);
        pool_info.pPoolSizes = pool_sizes;
        pool_info.flags = VK_DESCRIPTOR_POOL_CREATE_FREE_DESCRIPTOR_SET_BIT;
        err = vkCreateDescriptorPool(g_Device, &pool_info, g_Allocator, &g_DescriptorPool);
        check_vk_result(err);
    }
}

static void SetupVulkanWindow(ImGui_ImplVulkanH_Window* wd, VkSurfaceKHR surface, int width, int height)
{
    wd -> Surface = surface;

    // WSI == Window System Integration -> Translates certain functions to platform specific code
    // Check WSI support
    VkBool32 res;
    vkGetPhysicalDeviceSurfaceSupportKHR(g_PhysicalDevice, g_QueueFamily, wd->Surface, &res);
    if (res != VK_TRUE)
    {
        fprintf(stderr, "Error: no WSI support on physical device 0\n");
        exit(-1);
    }

    // Select surface format
    const VkFormat requestSurfaceImageFormat[] = { VK_FORMAT_B8G8R8A8_UNORM, VK_FORMAT_R8G8B8A8_UNORM, VK_FORMAT_B8G8R8_UNORM, VK_FORMAT_R8G8B8_UNORM };
    const VkColorSpaceKHR requestSurfaceColorSpace = VK_COLOR_SPACE_SRGB_NONLINEAR_KHR;
    wd -> SurfaceFormat = ImGui_ImplVulkanH_SelectSurfaceFormat(g_PhysicalDevice, wd->Surface, requestSurfaceImageFormat, (size_t)IM_ARRAYSIZE(requestSurfaceImageFormat), requestSurfaceColorSpace);

    // Select present mode
#ifdef APP_USE_UNLIMITED_FRAME_RATE
    VkPresentModeKHR present_modes[] = { VK_PRESENT_MODE_MAILBOX_KHR, VK_PRESENT_MODE_IMMEDIATE_KHR, VK_PRESENT_MODE_FIFO_KHR };
#else
    VkPresentModeKHR present_modes[] = { VK_PRESENT_MODE_FIFO_KHR };
#endif
    wd -> PresentMode= ImGui_ImplVulkanH_SelectPresentMode(g_PhysicalDevice, wd->Surface, &present_modes[0], IM_ARRAYSIZE(present_modes));

    // Create swapchain, renderpass, framebuffer, etc.
    IM_ASSERT(g_MinImageCount >= 2);
    ImGui_ImplVulkanH_CreateOrResizeWindow(g_Instance, g_PhysicalDevice, g_Device, wd, g_QueueFamily, g_Allocator, width, height, g_MinImageCount);
}

static ImVector<const char*> getVulkanExtensions()
{
    ImVector<const char*> extensions;
    uint32_t extensions_count = 0;
    const char** glfw_extensions = glfwGetRequiredInstanceExtensions(&extensions_count);
    for (uint32_t i = 0; i < extensions_count; i++)
    {
        extensions.push_back(glfw_extensions[i]);
    }

    return extensions;
}

void resizeSwapChain(GLFWwindow* window)
{
    int fb_width, fb_height;
    glfwGetFramebufferSize(window, &fb_width, &fb_height);
    if (fb_width > 0 && fb_height > 0 && (g_SwapChainRebuild || g_MainWindowData.Width != fb_width || g_MainWindowData.Height != fb_height))
    {
        ImGui_ImplVulkan_SetMinImageCount(g_MinImageCount);
        ImGui_ImplVulkanH_CreateOrResizeWindow(g_Instance, g_PhysicalDevice, g_Device, &g_MainWindowData, g_QueueFamily, g_Allocator, fb_width, fb_height, g_MinImageCount);
        g_MainWindowData.FrameIndex = 0;
        g_SwapChainRebuild = false;
    }
    if (glfwGetWindowAttrib(window, GLFW_ICONIFIED) != 0)
    {
        ImGui_ImplGlfw_Sleep(10);
    }
}

// Cleanup functions
static void CleanupVulkan()
{
    vkDestroyDescriptorPool(g_Device, g_DescriptorPool, g_Allocator);

#ifdef APP_USE_VULKAN_DEBUG_REPORT
    // Remove debug report callback
    auto f_vkDestroyDebugReportCallbackEXT = (PFN_vkDestroyDebugReportCallbackEXT)vkGetInstanceProcAddr(g_Instance, "vkDestroyDebugReportCallbackEXT");
    f_vkDestroyDebugReportCallbackEXT(g_Instance, g_DebugReport, g_Allocator);
#endif

    vkDestroyDevice(g_Device, g_Allocator);
    vkDestroyInstance(g_Instance, g_Allocator);
}

static void CleanupVulkanWindow()
{
    ImGui_ImplVulkanH_DestroyWindow(g_Instance, g_Device, &g_MainWindowData, g_Allocator);
}

static void cleanup(VkResult err, GLFWwindow* window)
{
    err = vkDeviceWaitIdle(g_Device);
    check_vk_result(err);
    ImGui_ImplVulkan_Shutdown();
    ImGui_ImplGlfw_Shutdown();
    ImGui::DestroyContext();

    CleanupVulkanWindow();
    CleanupVulkan();

    glfwDestroyWindow(window);
    glfwTerminate();
}

// Rendering
static void FrameRender(ImGui_ImplVulkanH_Window* wd, ImDrawData* draw_data)
{
    VkSemaphore image_acquired_semaphore  = wd -> FrameSemaphores[wd->SemaphoreIndex].ImageAcquiredSemaphore;
    VkSemaphore render_complete_semaphore = wd -> FrameSemaphores[wd->SemaphoreIndex].RenderCompleteSemaphore;
    VkResult err = vkAcquireNextImageKHR(g_Device, wd->Swapchain, UINT64_MAX, image_acquired_semaphore, VK_NULL_HANDLE, &wd->FrameIndex);
    if (err == VK_ERROR_OUT_OF_DATE_KHR || err == VK_SUBOPTIMAL_KHR)
    {
        g_SwapChainRebuild = true;
    }
    if (err == VK_ERROR_OUT_OF_DATE_KHR)
    {
        return;
    }
    if (err != VK_SUBOPTIMAL_KHR)
    {
        check_vk_result(err);
    }

    ImGui_ImplVulkanH_Frame* fd = &wd -> Frames[wd->FrameIndex];
    {
        err = vkWaitForFences(g_Device, 1, &fd->Fence, VK_TRUE, UINT64_MAX);
        check_vk_result(err);

        err = vkResetFences(g_Device, 1, &fd -> Fence);
        check_vk_result(err);
    }
    {
        err = vkResetCommandPool(g_Device, fd->CommandPool, 0);
        check_vk_result(err);
        VkCommandBufferBeginInfo info = {};
        info.sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO;
        info.flags |= VK_COMMAND_BUFFER_USAGE_ONE_TIME_SUBMIT_BIT;
        err = vkBeginCommandBuffer(fd->CommandBuffer, &info);
        check_vk_result(err);
    }
    {
        VkRenderPassBeginInfo info = {};
        info.sType = VK_STRUCTURE_TYPE_RENDER_PASS_BEGIN_INFO;
        info.renderPass = wd->RenderPass;
        info.framebuffer = fd->Framebuffer;
        info.renderArea.extent.width = wd->Width;
        info.renderArea.extent.height = wd->Height;
        info.clearValueCount = 1;
        info.pClearValues = &wd->ClearValue;
        vkCmdBeginRenderPass(fd->CommandBuffer, &info, VK_SUBPASS_CONTENTS_INLINE);
    }

    // Record imgui primitives into command buffer
    ImGui_ImplVulkan_RenderDrawData(draw_data, fd->CommandBuffer);

    // Submit command buffer
    vkCmdEndRenderPass(fd->CommandBuffer);
    {
        VkPipelineStageFlags wait_stage = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT;
        VkSubmitInfo info = {};
        info.sType = VK_STRUCTURE_TYPE_SUBMIT_INFO;
        info.waitSemaphoreCount = 1;
        info.pWaitSemaphores = &image_acquired_semaphore;
        info.pWaitDstStageMask = &wait_stage;
        info.commandBufferCount = 1;
        info.pCommandBuffers = &fd->CommandBuffer;
        info.signalSemaphoreCount = 1;
        info.pSignalSemaphores = &render_complete_semaphore;

        err = vkEndCommandBuffer(fd->CommandBuffer);
        check_vk_result(err);
        err = vkQueueSubmit(g_Queue, 1, &info, fd->Fence);
        check_vk_result(err);
    }
}

static void FramePresent(ImGui_ImplVulkanH_Window* wd)
{
    if (g_SwapChainRebuild)
    {
        return;
    }
    VkSemaphore render_complete_semaphore = wd->FrameSemaphores[wd->SemaphoreIndex].RenderCompleteSemaphore;
    VkPresentInfoKHR info = {};
    info.sType = VK_STRUCTURE_TYPE_PRESENT_INFO_KHR;
    info.waitSemaphoreCount = 1;
    info.pWaitSemaphores = &render_complete_semaphore;
    info.swapchainCount = 1;info.pSwapchains = &wd -> Swapchain;
    info.pImageIndices = &wd -> FrameIndex;
    VkResult err = vkQueuePresentKHR(g_Queue, &info);
    if (err == VK_ERROR_OUT_OF_DATE_KHR || err == VK_SUBOPTIMAL_KHR)
    {
        g_SwapChainRebuild = true;
    }
    if (err == VK_ERROR_OUT_OF_DATE_KHR)
    {
        return;
    }
    if (err != VK_SUBOPTIMAL_KHR)
    {
        check_vk_result(err);
    }
    wd->SemaphoreIndex = (wd->SemaphoreIndex +1) % wd->SemaphoreCount; // Use the next set of semaphores
}

// ImGui
static ImGuiIO setupImGuiContext(GLFWwindow* window, ImGui_ImplVulkanH_Window* wd)
{
    // Setup imgui context
    IMGUI_CHECKVERSION();
    ImGui::CreateContext();
    ImGuiIO& io = ImGui::GetIO(); (void)io;
    io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;       // Enable Keyboard Control
    io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;        // Enable Gamepad Control

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

    // Setup backends
    ImGui_ImplGlfw_InitForVulkan(window, true);
    ImGui_ImplVulkan_InitInfo init_info = {};
    init_info.Instance = g_Instance;
    init_info.PhysicalDevice = g_PhysicalDevice;
    init_info.Device = g_Device;
    init_info.QueueFamily = g_QueueFamily;
    init_info.Queue = g_Queue;
    init_info.PipelineCache = g_PipelineCache;
    init_info.DescriptorPool = g_DescriptorPool;
    init_info.RenderPass = wd->RenderPass;
    init_info.Subpass = 0;
    init_info.MinImageCount = g_MinImageCount;
    init_info.ImageCount = wd->ImageCount;
    init_info.MSAASamples = VK_SAMPLE_COUNT_1_BIT;
    init_info.Allocator = g_Allocator;
    init_info.CheckVkResultFn = check_vk_result;
    ImGui_ImplVulkan_Init(&init_info);

    // Load Fonts
    ImFont* font = io.Fonts->AddFontFromFileTTF("assets/fonts/RobotoMono-Regular.ttf", 17.0f);
    assert(font != nullptr && "Font loading failed!");

    return io;
}

void renderImGui(ImGui_ImplVulkanH_Window* wd, ImVec4 clear_color, ImGuiIO io)
{
    // Render imgui
    ImGui::Render();
    ImDrawData* main_draw_data = ImGui::GetDrawData();
    const bool main_is_minimized = (main_draw_data->DisplaySize.x <= 0.0f || main_draw_data->DisplaySize.y <= 0.0f);
    wd->ClearValue.color.float32[0] = clear_color.x * clear_color.w;
    wd->ClearValue.color.float32[1] = clear_color.y * clear_color.w;
    wd->ClearValue.color.float32[2] = clear_color.z * clear_color.w;
    wd->ClearValue.color.float32[3] = clear_color.w;
    if (!main_is_minimized)
    {
        FrameRender(wd, main_draw_data);
    }

    // Update and Render additional platform windows
    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
    {
        ImGui::UpdatePlatformWindows();
        ImGui::RenderPlatformWindowsDefault();
    }

    // Present Main Platform Window
    if (!main_is_minimized)
    {
        FramePresent(wd);
    }
}

void keyCallback(GLFWwindow* wd, int key, int scancode, int action, int mods)
{
    ImGui_ImplGlfw_KeyCallback(wd, key, scancode, action, mods);

    if (key == GLFW_KEY_B && action == GLFW_PRESS)
    {
        show_mainBar = !show_mainBar;
        printf("Toggle Main Menu Bar!\n");
    }

    if (key == GLFW_KEY_X && action == GLFW_PRESS)
    {
        printf("Closing window!!\n");
        glfwSetWindowShouldClose(wd, true);
    }
}

// Main
int main(int, char**)
{
    glfwSetErrorCallback(glfw_error_callback);
    if (!glfwInit())
    {
        return 1;
    }

    // Create window with Vulkan context
    glfwWindowHint(GLFW_CLIENT_API, GLFW_NO_API);
    GLFWwindow* window = glfwCreateWindow(1280, 720, "ImGUI + GLFW + Vulkan", nullptr, nullptr);
    if (!glfwVulkanSupported())
    {
        printf("GLFW: Vulkan not supported!\n");
        return 1;
    }

    SetupVulkan(getVulkanExtensions());

    // Create Window Surface
    VkSurfaceKHR surface;
    VkResult err = glfwCreateWindowSurface(g_Instance, window, g_Allocator, &surface);
    check_vk_result(err);

    // Create Framebuffers
    int w, h;
    glfwGetFramebufferSize(window, &w, &h);
    ImGui_ImplVulkanH_Window* wd = &g_MainWindowData;
    SetupVulkanWindow(wd, surface, w, h);

    ImGuiIO io = setupImGuiContext(window, wd);

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

    glfwSetKeyCallback(window, keyCallback);

    // Main Loop
    while (!glfwWindowShouldClose(window))
    {
        // Resize swap chain
        resizeSwapChain(window);

        // Start imgui frame
        ImGui_ImplVulkan_NewFrame();
        ImGui_ImplGlfw_NewFrame();
        ImGui::NewFrame();

        // If "B" is pressed, render the ImGui mainBar
        if (show_mainBar)
        {
            showMainBar(&show_mainBar);
        }

        // Render Dear ImGui windows
        renderImGui(wd, clear_color, io);

        // Pass info to profiler
        profiler.frame();
        profiler.batteryLogic();
        profiler.memoryLogic();
        float currentFps = profiler.getFPS();
        float currentBatteryLevel = profiler.getBatteryLevel();
        Profiler::RAMStats currentRAM = Profiler::getRAMStats();

        glfwPollEvents();
    }

    // Cleanup
    cleanup(err, window);

    return 0;
}