physical devices queue families yeah

src/main.cpp

@@ -11,6 +11,10 @@
 #include "fmt/base.h"
 #include "util/types.h"
 
+namespace vk {
+  using DebugUtilsMessengerUnique = vk::UniqueHandle<vk::DebugUtilsMessengerEXT, vk::DispatchLoaderDynamic>;
+}
+
 constexpr int WIDTH  = 800;
 constexpr int HEIGHT = 600;
 
@@ -36,9 +40,17 @@ class VulkanApp {
 
   vk::UniqueInstance mInstance;
 
-  vk::UniqueHandle<vk::DebugUtilsMessengerEXT, vk::DispatchLoaderDynamic> mDebugMessenger;
+  vk::DebugUtilsMessengerUnique mDebugMessenger;
   vk::DispatchLoaderDynamic     mLoader;
 
+  vk::PhysicalDevice mPhysicalDevice;
+
+  struct QueueFamilyIndices {
+    std::optional<u32> graphics_family;
+
+    fn isComplete() -> bool { return graphics_family.has_value(); }
+  };
+
   void initWindow() {
     glfwInit();
 
@@ -51,6 +63,55 @@ class VulkanApp {
   void initVulkan() {
     createInstance();
     setupDebugMessenger();
+    pickPhysicalDevice();
+  }
+
+  void mainLoop() {
+    while (!glfwWindowShouldClose(mWindow)) { glfwPollEvents(); }
+  }
+
+  void cleanup() {
+    glfwDestroyWindow(mWindow);
+    glfwTerminate();
+  }
+
+  fn createInstance() -> void {
+    if (enableValidationLayers && !checkValidationLayerSupport())
+      throw std::runtime_error("validation layers requested, but not available!");
+
+    vk::ApplicationInfo appInfo { .pApplicationName   = "Hello Triangle",
+                                  .applicationVersion = 1,
+                                  .pEngineName        = "No Engine",
+                                  .engineVersion      = 1,
+                                  .apiVersion         = VK_API_VERSION_1_0 };
+
+    // Retrieve extensions using custom function
+    std::vector<const char*> extensions = getRequiredExtensions();
+
+    // Enable the portability extension and set flags
+    extensions.push_back("VK_KHR_portability_enumeration");
+
+    vk::InstanceCreateInfo createInfo {
+      .flags                   = vk::InstanceCreateFlagBits::eEnumeratePortabilityKHR,
+      .pApplicationInfo        = &appInfo,
+      .enabledLayerCount       = enableValidationLayers ? static_cast<uint32_t>(validationLayers.size()) : 0,
+      .ppEnabledLayerNames     = enableValidationLayers ? validationLayers.data() : nullptr,
+      .enabledExtensionCount   = static_cast<uint32_t>(extensions.size()),
+      .ppEnabledExtensionNames = extensions.data()
+    };
+
+#ifndef NDEBUG
+    fmt::println("Available extensions:");
+
+    for (const char* extension : extensions) fmt::println("\t{}", extension);
+#endif
+
+    try {
+      mInstance = vk::createInstanceUnique(createInfo);
+      mLoader   = vk::DispatchLoaderDynamic(mInstance.get(), vkGetInstanceProcAddr);
+    } catch (const vk::SystemError& err) {
+      throw std::runtime_error("Failed to create instance: " + std::string(err.what()));
+    }
   }
 
   void setupDebugMessenger() {
@@ -70,53 +131,70 @@ class VulkanApp {
     mDebugMessenger = mInstance->createDebugUtilsMessengerEXTUnique(messengerCreateInfo, nullptr, mLoader);
   }
 
-  void mainLoop() {
+  fn pickPhysicalDevice() -> void {
-    while (!glfwWindowShouldClose(mWindow)) { glfwPollEvents(); }
+    std::vector<vk::PhysicalDevice> devices = mInstance->enumeratePhysicalDevices();
+
+    if (devices.empty())
+      throw std::runtime_error("Failed to find GPUs with Vulkan support!");
+
+#ifndef NDEBUG
+    fmt::println("Available devices:");
+#endif
+
+    for (const auto& device : devices) {
+#ifndef NDEBUG
+      vk::PhysicalDeviceProperties properties = device.getProperties();
+      fmt::println("Device: {}", properties.deviceName.data());
+#endif
+
+      if (isDeviceSuitable(device)) {
+        mPhysicalDevice = device;
+        break;
+      }
     }
 
-  void cleanup() {
+    if (!mPhysicalDevice)
-    // NOTE: instance destruction is handled by UniqueInstance
+      throw std::runtime_error("Failed to find a suitable GPU!");
-
-    glfwDestroyWindow(mWindow);
-
-    glfwTerminate();
   }
 
-  fn createInstance() -> void {
+  static fn isDeviceSuitable(vk::PhysicalDevice device) -> bool {
-    if (enableValidationLayers && !checkValidationLayerSupport())
+    QueueFamilyIndices indices = findQueueFamilies(device);
-      throw std::runtime_error("validation layers requested, but not available!");
 
-    vk::ApplicationInfo appInfo { .pApplicationName   = "Hello Triangle",
+    return indices.isComplete();
-                                  .applicationVersion = 1,
-                                  .pEngineName        = "No Engine",
-                                  .engineVersion      = 1,
-                                  .apiVersion         = VK_API_VERSION_1_0 };
-
-    // Retrieve extensions using custom function
-    std::vector<const char*> extensions = getRequiredExtensions();
-
-    vk::InstanceCreateInfo createInfo {
-      .pApplicationInfo    = &appInfo,
-      .enabledLayerCount   = enableValidationLayers ? static_cast<uint32_t>(validationLayers.size()) : 0,
-      .ppEnabledLayerNames = enableValidationLayers ? validationLayers.data() : nullptr
-    };
-
-    // Enable the portability extension and set flags
-    extensions.push_back(VK_KHR_PORTABILITY_ENUMERATION_EXTENSION_NAME);
-    createInfo.setEnabledExtensionCount(static_cast<uint32_t>(extensions.size()))
-      .setPpEnabledExtensionNames(extensions.data())
-      .setFlags(vk::InstanceCreateFlagBits::eEnumeratePortabilityKHR);
-
-    fmt::println("Available extensions:");
-
-    for (const char* extension : extensions) fmt::println("\t{}", extension);
-
-    try {
-      mInstance = vk::createInstanceUnique(createInfo);
-      mLoader   = vk::DispatchLoaderDynamic(mInstance.get(), vkGetInstanceProcAddr);
-    } catch (const vk::SystemError& err) {
-      throw std::runtime_error("Failed to create instance: " + std::string(err.what()));
   }
+
+  static fn findQueueFamilies(vk::PhysicalDevice device) -> QueueFamilyIndices {
+    QueueFamilyIndices indices;
+
+    std::vector<vk::QueueFamilyProperties> queueFamilies = device.getQueueFamilyProperties();
+
+    for (u32 i = 0; i < queueFamilies.size(); i++) {
+      if (queueFamilies[i].queueFlags & vk::QueueFlagBits::eGraphics)
+        indices.graphics_family = i;
+
+      if (indices.isComplete())
+        break;
+    }
+
+    return indices;
+  }
+
+  static fn getRequiredExtensions() -> std::vector<const char*> {
+    u32          glfwExtensionCount = 0;
+    const char** glfwExtensions     = nullptr;
+    glfwExtensions                  = glfwGetRequiredInstanceExtensions(&glfwExtensionCount);
+
+    std::vector<const char*> extensions;
+
+    if (glfwExtensions) {
+      std::span<const char*> extSpan(glfwExtensions, glfwExtensionCount);
+      extensions.assign(extSpan.begin(), extSpan.end());
+    }
+
+    if (enableValidationLayers)
+      extensions.push_back("VK_EXT_debug_utils");
+
+    return extensions;
   }
 
   static fn checkValidationLayerSupport() -> bool {
@@ -138,24 +216,6 @@ class VulkanApp {
     return true;
   }
 
-  static fn getRequiredExtensions() -> std::vector<const char*> {
-    u32          glfwExtensionCount = 0;
-    const char** glfwExtensions     = nullptr;
-    glfwExtensions                  = glfwGetRequiredInstanceExtensions(&glfwExtensionCount);
-
-    std::vector<const char*> extensions;
-
-    if (glfwExtensions) {
-      std::span<const char*> extSpan(glfwExtensions, glfwExtensionCount);
-      extensions.assign(extSpan.begin(), extSpan.end());
-    }
-
-    if (enableValidationLayers)
-      extensions.push_back("VK_EXT_debug_utils");
-
-    return extensions;
-  }
-
   static VKAPI_ATTR fn VKAPI_CALL debugCallback(
     VkDebugUtilsMessageSeverityFlagBitsEXT /*messageSeverity*/,
     VkDebugUtilsMessageTypeFlagsEXT /*messageType*/,