02_validation_layers.cpp

#include <iostream>
#include <stdexcept>
#include <vector>
#include <cstring>
#include <cstdlib>
#include <memory>
#include <algorithm>

#ifdef __INTELLISENSE__
#include <vulkan/vulkan_raii.hpp>
#else
import vulkan_hpp;
#endif

#include <vulkan/vk_platform.h>

#define GLFW_INCLUDE_VULKAN // REQUIRED only for GLFW CreateWindowSurface.
#include <GLFW/glfw3.h>

constexpr uint32_t WIDTH = 800;
constexpr uint32_t HEIGHT = 600;

const std::vector validationLayers = {
    "VK_LAYER_KHRONOS_validation"
};

#ifdef NDEBUG
constexpr bool enableValidationLayers = false;
#else
constexpr bool enableValidationLayers = true;
#endif

class HelloTriangleApplication {
public:
    void run() {
        initWindow();
        initVulkan();
        mainLoop();
        cleanup();
    }

private:
    GLFWwindow* window = nullptr;

    vk::raii::Context  context;
    vk::raii::Instance instance = nullptr;
    vk::raii::DebugUtilsMessengerEXT debugMessenger = nullptr;

    void initWindow() {
        glfwInit();

        glfwWindowHint(GLFW_CLIENT_API, GLFW_NO_API);
        glfwWindowHint(GLFW_RESIZABLE, GLFW_FALSE);

        window = glfwCreateWindow(WIDTH, HEIGHT, "Vulkan", nullptr, nullptr);
    }

    void initVulkan() {
        createInstance();
        setupDebugMessenger();
    }

    void mainLoop() {
        while (!glfwWindowShouldClose(window)) {
            glfwPollEvents();
        }
    }

    void cleanup() {
        glfwDestroyWindow(window);

        glfwTerminate();
    }

    void createInstance() {
        constexpr vk::ApplicationInfo appInfo{ .pApplicationName   = "Hello Triangle",
                    .applicationVersion = VK_MAKE_VERSION( 1, 0, 0 ),
                    .pEngineName        = "No Engine",
                    .engineVersion      = VK_MAKE_VERSION( 1, 0, 0 ),
                    .apiVersion         = vk::ApiVersion14 };

        // Get the required layers
        std::vector<char const*> requiredLayers;
        if (enableValidationLayers) {
            requiredLayers.assign(validationLayers.begin(), validationLayers.end());
        }

        // Check if the required layers are supported by the Vulkan implementation.
        auto layerProperties = context.enumerateInstanceLayerProperties();
        for (auto const& requiredLayer : requiredLayers)
        {
            if (std::ranges::none_of(layerProperties,
                                     [requiredLayer](auto const& layerProperty)
                                     { return strcmp(layerProperty.layerName, requiredLayer) == 0; }))
            {
                throw std::runtime_error("Required layer not supported: " + std::string(requiredLayer));
            }
        }

        // Get the required extensions.
        auto requiredExtensions = getRequiredExtensions();

        // Check if the required extensions are supported by the Vulkan implementation.
        auto extensionProperties = context.enumerateInstanceExtensionProperties();
        for (auto const & requiredExtension : requiredExtensions)
        {
            if (std::ranges::none_of(extensionProperties,
                                     [requiredExtension](auto const& extensionProperty)
                                     { return strcmp(extensionProperty.extensionName, requiredExtension) == 0; }))
            {
                throw std::runtime_error("Required extension not supported: " + std::string(requiredExtension));
            }
        }

        vk::InstanceCreateInfo createInfo{
            .pApplicationInfo        = &appInfo,
            .enabledLayerCount       = static_cast<uint32_t>(requiredLayers.size()),
            .ppEnabledLayerNames     = requiredLayers.data(),
            .enabledExtensionCount   = static_cast<uint32_t>(requiredExtensions.size()),
            .ppEnabledExtensionNames = requiredExtensions.data() };
        instance = vk::raii::Instance(context, createInfo);
    }

    void setupDebugMessenger() {
        if (!enableValidationLayers) return;

        vk::DebugUtilsMessageSeverityFlagsEXT severityFlags( vk::DebugUtilsMessageSeverityFlagBitsEXT::eVerbose | vk::DebugUtilsMessageSeverityFlagBitsEXT::eWarning | vk::DebugUtilsMessageSeverityFlagBitsEXT::eError );
        vk::DebugUtilsMessageTypeFlagsEXT    messageTypeFlags( vk::DebugUtilsMessageTypeFlagBitsEXT::eGeneral | vk::DebugUtilsMessageTypeFlagBitsEXT::ePerformance | vk::DebugUtilsMessageTypeFlagBitsEXT::eValidation );
        vk::DebugUtilsMessengerCreateInfoEXT debugUtilsMessengerCreateInfoEXT{
            .messageSeverity = severityFlags,
            .messageType = messageTypeFlags,
            .pfnUserCallback = &debugCallback
            };
        debugMessenger = instance.createDebugUtilsMessengerEXT(debugUtilsMessengerCreateInfoEXT);
    }

    std::vector<const char*> getRequiredExtensions() {
        uint32_t glfwExtensionCount = 0;
        auto glfwExtensions = glfwGetRequiredInstanceExtensions(&glfwExtensionCount);

        std::vector extensions(glfwExtensions, glfwExtensions + glfwExtensionCount);
        if (enableValidationLayers) {
            extensions.push_back(vk::EXTDebugUtilsExtensionName );
        }

        return extensions;
    }

    static VKAPI_ATTR vk::Bool32 VKAPI_CALL debugCallback(vk::DebugUtilsMessageSeverityFlagBitsEXT severity, vk::DebugUtilsMessageTypeFlagsEXT type, const vk::DebugUtilsMessengerCallbackDataEXT* pCallbackData, void*) {
        if (severity == vk::DebugUtilsMessageSeverityFlagBitsEXT::eError || severity == vk::DebugUtilsMessageSeverityFlagBitsEXT::eWarning) {
            std::cerr << "validation layer: type " << to_string(type) << " msg: " << pCallbackData->pMessage << std::endl;
        }

        return vk::False;
    }
};

int main() {
    try {
        HelloTriangleApplication app;
        app.run();
    } catch (const std::exception& e) {
        std::cerr << e.what() << std::endl;
        return EXIT_FAILURE;
    }

    return EXIT_SUCCESS;
}