more vks, stupid mutlistep build, and imgui

1 files changed, 581 insertions, 0 deletions

diff --git a/lib/imgui-1.90.7/examples/example_sdl2_vulkan/main.cpp b/lib/imgui-1.90.7/examples/example_sdl2_vulkan/main.cpp
new file mode 100644
index 0000000..df0db4d
--- /dev/null
+++ b/lib/imgui-1.90.7/examples/example_sdl2_vulkan/main.cpp
@@ -0,0 +1,581 @@
+// Dear ImGui: standalone example application for SDL2 + Vulkan
+
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// Important note to the reader who wish to integrate imgui_impl_vulkan.cpp/.h in their own engine/app.
+// - Common ImGui_ImplVulkan_XXX functions and structures are used to interface with imgui_impl_vulkan.cpp/.h.
+//   You will use those if you want to use this rendering backend in your engine/app.
+// - Helper ImGui_ImplVulkanH_XXX functions and structures are only used by this example (main.cpp) and by
+//   the backend itself (imgui_impl_vulkan.cpp), but should PROBABLY NOT be used by your own engine/app code.
+// Read comments in imgui_impl_vulkan.h.
+
+#include "imgui.h"
+#include "imgui_impl_sdl2.h"
+#include "imgui_impl_vulkan.h"
+#include <stdio.h>          // printf, fprintf
+#include <stdlib.h>         // abort
+#include <SDL.h>
+#include <SDL_vulkan.h>
+
+// Volk headers
+#ifdef IMGUI_IMPL_VULKAN_USE_VOLK
+#define VOLK_IMPLEMENTATION
+#include <Volk/volk.h>
+#endif
+
+//#define APP_USE_UNLIMITED_FRAME_RATE
+#ifdef _DEBUG
+#define APP_USE_VULKAN_DEBUG_REPORT
+#endif
+
+// 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 VkDebugReportCallbackEXT g_DebugReport = 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 void check_vk_result(VkResult err)
+{
+    if (err == 0)
+        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)
+{
+    (void)flags; (void)object; (void)location; (void)messageCode; (void)pUserData; (void)pLayerPrefix; // Unused arguments
+    fprintf(stderr, "[vulkan] Debug report from ObjectType: %i\nMessage: %s\n\n", objectType, pMessage);
+    return VK_FALSE;
+}
+#endif // APP_USE_VULKAN_DEBUG_REPORT
+
+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;
+}
+
+static VkPhysicalDevice SetupVulkan_SelectPhysicalDevice()
+{
+    uint32_t gpu_count;
+    VkResult err = vkEnumeratePhysicalDevices(g_Instance, &gpu_count, nullptr);
+    check_vk_result(err);
+    IM_ASSERT(gpu_count > 0);
+
+    ImVector<VkPhysicalDevice> gpus;
+    gpus.resize(gpu_count);
+    err = vkEnumeratePhysicalDevices(g_Instance, &gpu_count, gpus.Data);
+    check_vk_result(err);
+
+    // If a number >1 of GPUs got reported, find discrete GPU if present, or use first one available. This covers
+    // most common cases (multi-gpu/integrated+dedicated graphics). Handling more complicated setups (multiple
+    // dedicated GPUs) is out of scope of this sample.
+    for (VkPhysicalDevice& device : gpus)
+    {
+        VkPhysicalDeviceProperties properties;
+        vkGetPhysicalDeviceProperties(device, &properties);
+        if (properties.deviceType == VK_PHYSICAL_DEVICE_TYPE_DISCRETE_GPU)
+            return device;
+    }
+
+    // Use first GPU (Integrated) is a Discrete one is not available.
+    if (gpu_count > 0)
+        return gpus[0];
+    return VK_NULL_HANDLE;
+}
+
+static void SetupVulkan(ImVector<const char*> instance_extensions)
+{
+    VkResult err;
+#ifdef IMGUI_IMPL_VULKAN_USE_VOLK
+    volkInitialize();
+#endif
+
+    // Create Vulkan Instance
+    {
+        VkInstanceCreateInfo create_info = {};
+        create_info.sType = VK_STRUCTURE_TYPE_INSTANCE_CREATE_INFO;
+
+        // Enumerate 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
+
+        // Enabling 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);
+#ifdef IMGUI_IMPL_VULKAN_USE_VOLK
+        volkLoadInstance(g_Instance);
+#endif
+
+        // Setup the 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_CALLBACK_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 = SetupVulkan_SelectPhysicalDevice();
+
+    // Select graphics queue family
+    {
+        uint32_t count;
+        vkGetPhysicalDeviceQueueFamilyProperties(g_PhysicalDevice, &count, nullptr);
+        VkQueueFamilyProperties* queues = (VkQueueFamilyProperties*)malloc(sizeof(VkQueueFamilyProperties) * count);
+        vkGetPhysicalDeviceQueueFamilyProperties(g_PhysicalDevice, &count, queues);
+        for (uint32_t i = 0; i < count; i++)
+            if (queues[i].queueFlags & VK_QUEUE_GRAPHICS_BIT)
+            {
+                g_QueueFamily = i;
+                break;
+            }
+        free(queues);
+        IM_ASSERT(g_QueueFamily != (uint32_t)-1);
+    }
+
+    // Create Logical Device (with 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);
+    }
+
+    // Create Descriptor Pool
+    // The example only requires a single combined image sampler descriptor for the font image and only uses one descriptor set (for that)
+    // If you wish to load e.g. additional textures you may need to alter pools sizes.
+    {
+        VkDescriptorPoolSize pool_sizes[] =
+        {
+            { VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 1 },
+        };
+        VkDescriptorPoolCreateInfo pool_info = {};
+        pool_info.sType = VK_STRUCTURE_TYPE_DESCRIPTOR_POOL_CREATE_INFO;
+        pool_info.flags = VK_DESCRIPTOR_POOL_CREATE_FREE_DESCRIPTOR_SET_BIT;
+        pool_info.maxSets = 1;
+        pool_info.poolSizeCount = (uint32_t)IM_ARRAYSIZE(pool_sizes);
+        pool_info.pPoolSizes = pool_sizes;
+        err = vkCreateDescriptorPool(g_Device, &pool_info, g_Allocator, &g_DescriptorPool);
+        check_vk_result(err);
+    }
+}
+
+// All the ImGui_ImplVulkanH_XXX structures/functions are optional helpers used by the demo.
+// Your real engine/app may not use them.
+static void SetupVulkanWindow(ImGui_ImplVulkanH_Window* wd, VkSurfaceKHR surface, int width, int height)
+{
+    wd->Surface = surface;
+
+    // Check for 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_COLORSPACE_SRGB_NONLINEAR_KHR;
+    wd->SurfaceFormat = ImGui_ImplVulkanH_SelectSurfaceFormat(g_PhysicalDevice, wd->Surface, requestSurfaceImageFormat, (size_t)IM_ARRAYSIZE(requestSurfaceImageFormat), requestSurfaceColorSpace);
+
+    // Select Present Mode
+#ifdef APP_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));
+    //printf("[vulkan] Selected PresentMode = %d\n", wd->PresentMode);
+
+    // 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 void CleanupVulkan()
+{
+    vkDestroyDescriptorPool(g_Device, g_DescriptorPool, g_Allocator);
+
+#ifdef APP_USE_VULKAN_DEBUG_REPORT
+    // Remove the debug report callback
+    auto f_vkDestroyDebugReportCallbackEXT = (PFN_vkDestroyDebugReportCallbackEXT)vkGetInstanceProcAddr(g_Instance, "vkDestroyDebugReportCallbackEXT");
+    f_vkDestroyDebugReportCallbackEXT(g_Instance, g_DebugReport, g_Allocator);
+#endif // APP_USE_VULKAN_DEBUG_REPORT
+
+    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 FrameRender(ImGui_ImplVulkanH_Window* wd, ImDrawData* draw_data)
+{
+    VkResult err;
+
+    VkSemaphore image_acquired_semaphore  = wd->FrameSemaphores[wd->SemaphoreIndex].ImageAcquiredSemaphore;
+    VkSemaphore render_complete_semaphore = wd->FrameSemaphores[wd->SemaphoreIndex].RenderCompleteSemaphore;
+    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;
+        return;
+    }
+    check_vk_result(err);
+
+    ImGui_ImplVulkanH_Frame* fd = &wd->Frames[wd->FrameIndex];
+    {
+        err = vkWaitForFences(g_Device, 1, &fd->Fence, VK_TRUE, UINT64_MAX);    // wait indefinitely instead of periodically checking
+        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 dear 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;
+        return;
+    }
+    check_vk_result(err);
+    wd->SemaphoreIndex = (wd->SemaphoreIndex + 1) % wd->SemaphoreCount; // Now we can use the next set of semaphores
+}
+
+// Main code
+int main(int, char**)
+{
+    // Setup SDL
+    if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER | SDL_INIT_GAMECONTROLLER) != 0)
+    {
+        printf("Error: %s\n", SDL_GetError());
+        return -1;
+    }
+
+    // From 2.0.18: Enable native IME.
+#ifdef SDL_HINT_IME_SHOW_UI
+    SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1");
+#endif
+
+    // Create window with Vulkan graphics context
+    SDL_WindowFlags window_flags = (SDL_WindowFlags)(SDL_WINDOW_VULKAN | SDL_WINDOW_RESIZABLE | SDL_WINDOW_ALLOW_HIGHDPI);
+    SDL_Window* window = SDL_CreateWindow("Dear ImGui SDL2+Vulkan example", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 1280, 720, window_flags);
+    if (window == nullptr)
+    {
+        printf("Error: SDL_CreateWindow(): %s\n", SDL_GetError());
+        return -1;
+    }
+
+    ImVector<const char*> extensions;
+    uint32_t extensions_count = 0;
+    SDL_Vulkan_GetInstanceExtensions(window, &extensions_count, nullptr);
+    extensions.resize(extensions_count);
+    SDL_Vulkan_GetInstanceExtensions(window, &extensions_count, extensions.Data);
+    SetupVulkan(extensions);
+
+    // Create Window Surface
+    VkSurfaceKHR surface;
+    VkResult err;
+    if (SDL_Vulkan_CreateSurface(window, g_Instance, &surface) == 0)
+    {
+        printf("Failed to create Vulkan surface.\n");
+        return 1;
+    }
+
+    // Create Framebuffers
+    int w, h;
+    SDL_GetWindowSize(window, &w, &h);
+    ImGui_ImplVulkanH_Window* wd = &g_MainWindowData;
+    SetupVulkanWindow(wd, surface, w, h);
+
+    // Setup Dear ImGui context
+    IMGUI_CHECKVERSION();
+    ImGui::CreateContext();
+    ImGuiIO& io = ImGui::GetIO(); (void)io;
+    io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
+    io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+
+    // Setup Dear ImGui style
+    ImGui::StyleColorsDark();
+    //ImGui::StyleColorsLight();
+
+    // Setup Platform/Renderer backends
+    ImGui_ImplSDL2_InitForVulkan(window);
+    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
+    // - If no fonts are loaded, dear imgui will use the default font. You can also load multiple fonts and use ImGui::PushFont()/PopFont() to select them.
+    // - AddFontFromFileTTF() will return the ImFont* so you can store it if you need to select the font among multiple.
+    // - If the file cannot be loaded, the function will return a nullptr. Please handle those errors in your application (e.g. use an assertion, or display an error and quit).
+    // - The fonts will be rasterized at a given size (w/ oversampling) and stored into a texture when calling ImFontAtlas::Build()/GetTexDataAsXXXX(), which ImGui_ImplXXXX_NewFrame below will call.
+    // - Use '#define IMGUI_ENABLE_FREETYPE' in your imconfig file to use Freetype for higher quality font rendering.
+    // - Read 'docs/FONTS.md' for more instructions and details.
+    // - Remember that in C/C++ if you want to include a backslash \ in a string literal you need to write a double backslash \\ !
+    //io.Fonts->AddFontDefault();
+    //io.Fonts->AddFontFromFileTTF("c:\\Windows\\Fonts\\segoeui.ttf", 18.0f);
+    //io.Fonts->AddFontFromFileTTF("../../misc/fonts/DroidSans.ttf", 16.0f);
+    //io.Fonts->AddFontFromFileTTF("../../misc/fonts/Roboto-Medium.ttf", 16.0f);
+    //io.Fonts->AddFontFromFileTTF("../../misc/fonts/Cousine-Regular.ttf", 15.0f);
+    //ImFont* font = io.Fonts->AddFontFromFileTTF("c:\\Windows\\Fonts\\ArialUni.ttf", 18.0f, nullptr, io.Fonts->GetGlyphRangesJapanese());
+    //IM_ASSERT(font != nullptr);
+
+    // Our state
+    bool show_demo_window = true;
+    bool show_another_window = false;
+    ImVec4 clear_color = ImVec4(0.45f, 0.55f, 0.60f, 1.00f);
+
+    // Main loop
+    bool done = false;
+    while (!done)
+    {
+        // Poll and handle events (inputs, window resize, etc.)
+        // You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs.
+        // - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application, or clear/overwrite your copy of the mouse data.
+        // - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data.
+        // Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
+        SDL_Event event;
+        while (SDL_PollEvent(&event))
+        {
+            ImGui_ImplSDL2_ProcessEvent(&event);
+            if (event.type == SDL_QUIT)
+                done = true;
+            if (event.type == SDL_WINDOWEVENT && event.window.event == SDL_WINDOWEVENT_CLOSE && event.window.windowID == SDL_GetWindowID(window))
+                done = true;
+        }
+
+        // Resize swap chain?
+        if (g_SwapChainRebuild)
+        {
+            int width, height;
+            SDL_GetWindowSize(window, &width, &height);
+            if (width > 0 && height > 0)
+            {
+                ImGui_ImplVulkan_SetMinImageCount(g_MinImageCount);
+                ImGui_ImplVulkanH_CreateOrResizeWindow(g_Instance, g_PhysicalDevice, g_Device, &g_MainWindowData, g_QueueFamily, g_Allocator, width, height, g_MinImageCount);
+                g_MainWindowData.FrameIndex = 0;
+                g_SwapChainRebuild = false;
+            }
+        }
+
+        // Start the Dear ImGui frame
+        ImGui_ImplVulkan_NewFrame();
+        ImGui_ImplSDL2_NewFrame();
+        ImGui::NewFrame();
+
+        // 1. Show the big demo window (Most of the sample code is in ImGui::ShowDemoWindow()! You can browse its code to learn more about Dear ImGui!).
+        if (show_demo_window)
+            ImGui::ShowDemoWindow(&show_demo_window);
+
+        // 2. Show a simple window that we create ourselves. We use a Begin/End pair to create a named window.
+        {
+            static float f = 0.0f;
+            static int counter = 0;
+
+            ImGui::Begin("Hello, world!");                          // Create a window called "Hello, world!" and append into it.
+
+            ImGui::Text("This is some useful text.");               // Display some text (you can use a format strings too)
+            ImGui::Checkbox("Demo Window", &show_demo_window);      // Edit bools storing our window open/close state
+            ImGui::Checkbox("Another Window", &show_another_window);
+
+            ImGui::SliderFloat("float", &f, 0.0f, 1.0f);            // Edit 1 float using a slider from 0.0f to 1.0f
+            ImGui::ColorEdit3("clear color", (float*)&clear_color); // Edit 3 floats representing a color
+
+            if (ImGui::Button("Button"))                            // Buttons return true when clicked (most widgets return true when edited/activated)
+                counter++;
+            ImGui::SameLine();
+            ImGui::Text("counter = %d", counter);
+
+            ImGui::Text("Application average %.3f ms/frame (%.1f FPS)", 1000.0f / io.Framerate, io.Framerate);
+            ImGui::End();
+        }
+
+        // 3. Show another simple window.
+        if (show_another_window)
+        {
+            ImGui::Begin("Another Window", &show_another_window);   // Pass a pointer to our bool variable (the window will have a closing button that will clear the bool when clicked)
+            ImGui::Text("Hello from another window!");
+            if (ImGui::Button("Close Me"))
+                show_another_window = false;
+            ImGui::End();
+        }
+
+        // Rendering
+        ImGui::Render();
+        ImDrawData* draw_data = ImGui::GetDrawData();
+        const bool is_minimized = (draw_data->DisplaySize.x <= 0.0f || draw_data->DisplaySize.y <= 0.0f);
+        if (!is_minimized)
+        {
+            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;
+            FrameRender(wd, draw_data);
+            FramePresent(wd);
+        }
+    }
+
+    // Cleanup
+    err = vkDeviceWaitIdle(g_Device);
+    check_vk_result(err);
+    ImGui_ImplVulkan_Shutdown();
+    ImGui_ImplSDL2_Shutdown();
+    ImGui::DestroyContext();
+
+    CleanupVulkanWindow();
+    CleanupVulkan();
+
+    SDL_DestroyWindow(window);
+    SDL_Quit();
+
+    return 0;
+}