Add ImGui

- Initial ImGui commit, add support for showing demo window in Copium
  Engine

CopiumEngine/src/copium/core/Application.cpp

@@ -15,6 +15,8 @@
 
 #include <glm/gtc/matrix_transform.hpp>
 
+#include <imgui.h>
+
 namespace Copium
 {
   const std::vector<Vertex> vertices = {
@@ -74,6 +76,7 @@ namespace Copium
       return true;
 
     RecordCommandBuffer();
+
     Vulkan::GetSwapChain().SubmitToGraphicsQueue(*commandBuffer);
 
     Vulkan::GetSwapChain().EndPresent();
@@ -164,6 +167,8 @@ namespace Copium
 
   void Application::RecordCommandBuffer()
   {
+    Vulkan::GetImGuiInstance().Begin();
+    ImGui::ShowDemoWindow();
     commandBuffer->Begin();
 
     Framebuffer& fb = AssetManager::GetAsset<Framebuffer>(framebuffer);
@@ -193,6 +198,9 @@ namespace Copium
     meshPassthrough->Bind(*commandBuffer);
     meshPassthrough->Render(*commandBuffer);
 
+    Vulkan::GetImGuiInstance().End();
+    Vulkan::GetImGuiInstance().Render(*commandBuffer);
+
     Vulkan::GetSwapChain().EndFrameBuffer(*commandBuffer);
     commandBuffer->End();
   }

CopiumEngine/src/copium/core/Device.cpp

@@ -18,6 +18,16 @@ namespace Copium
     vkDestroyDevice(device, nullptr);
   }
 
+  uint32_t Device::GetGraphicsQueueFamily() const
+  {
+    return graphicsQueueIndex;
+  }
+
+  uint32_t Device::GetPresentQueueFamily() const
+  {
+    return presentQueueIndex;
+  }
+
   VkQueue Device::GetGraphicsQueue() const
   {
     return graphicsQueue;

CopiumEngine/src/copium/core/Device.h

@@ -27,6 +27,8 @@ namespace Copium
     Device();
     ~Device();
     
+    uint32_t GetGraphicsQueueFamily() const;
+    uint32_t GetPresentQueueFamily() const;
     VkQueue GetGraphicsQueue() const;
     VkQueue GetPresentQueue() const;
     VkCommandPool GetCommandPool() const;

CopiumEngine/src/copium/core/ImGuiInstance.cpp

@@ -0,0 +1,77 @@
+#include "ImGuiInstance.h"
+
+#include "copium/core/Vulkan.h"
+#include "copium/buffer/CommandBufferScoped.h"
+
+#include <imgui.h>
+#include <backends/imgui_impl_glfw.h>
+#include <backends/imgui_impl_vulkan.h>
+
+namespace Copium
+{
+  ImGuiInstance::ImGuiInstance()
+    : descriptorPool{std::make_unique<DescriptorPool>()}
+  {
+    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_ImplGlfw_InitForVulkan(Vulkan::GetWindow().GetWindow(), true);
+    ImGui_ImplVulkan_InitInfo init_info = {};
+    init_info.Instance = Vulkan::GetInstance();
+    init_info.PhysicalDevice = Vulkan::GetDevice().GetPhysicalDevice();
+    init_info.Device = Vulkan::GetDevice();
+    init_info.QueueFamily = Vulkan::GetDevice().GetGraphicsQueueFamily();
+    init_info.Queue = Vulkan::GetDevice().GetGraphicsQueue();
+    init_info.PipelineCache = VK_NULL_HANDLE;
+    init_info.DescriptorPool = *descriptorPool.get();
+    init_info.Subpass = 0;
+    init_info.MinImageCount = SwapChain::MAX_FRAMES_IN_FLIGHT;
+    init_info.ImageCount = Vulkan::GetSwapChain().GetImageCount();
+    init_info.MSAASamples = VK_SAMPLE_COUNT_1_BIT;
+    init_info.Allocator = nullptr;
+    init_info.CheckVkResultFn = CheckVkResult;
+    ImGui_ImplVulkan_Init(&init_info, Vulkan::GetSwapChain().GetRenderPass());
+    {
+      CommandBufferScoped commandBuffer;
+      ImGui_ImplVulkan_CreateFontsTexture(commandBuffer);
+    }
+    ImGui_ImplVulkan_DestroyFontUploadObjects();
+  }
+
+  ImGuiInstance::~ImGuiInstance()
+  {
+    ImGui_ImplVulkan_Shutdown();
+    ImGui_ImplGlfw_Shutdown();
+    ImGui::DestroyContext();
+  }
+
+  void ImGuiInstance::Begin()
+  {
+    ImGui_ImplVulkan_NewFrame();
+    ImGui_ImplGlfw_NewFrame();
+    ImGui::NewFrame();
+  }
+
+  void ImGuiInstance::End()
+  {
+    ImGui::EndFrame();
+  }
+
+  void ImGuiInstance::Render(CommandBuffer& commandBuffer)
+  {
+    ImGui::Render();
+    ImDrawData* draw_data = ImGui::GetDrawData();
+    ImGui_ImplVulkan_RenderDrawData(draw_data, commandBuffer);
+  }
+
+  void ImGuiInstance::CheckVkResult(VkResult err)
+  {
+    CP_VK_ASSERT(err, "Failed to initialize ImGui");
+  }
+}

CopiumEngine/src/copium/core/ImGuiInstance.h

@@ -0,0 +1,28 @@
+#pragma once
+
+#include <memory>
+
+#include "copium/buffer/CommandBuffer.h"
+#include "copium/pipeline/DescriptorPool.h"
+
+namespace Copium
+{
+  class ImGuiInstance
+  {
+    CP_DELETE_COPY_AND_MOVE_CTOR(ImGuiInstance);
+
+  private:
+    std::unique_ptr<DescriptorPool> descriptorPool;
+
+  public:
+    ImGuiInstance();
+    ~ImGuiInstance();
+
+    void Begin();
+    void End();
+    void Render(CommandBuffer& commandBuffer);
+
+  private:
+    static void CheckVkResult(VkResult err);
+  };
+}

CopiumEngine/src/copium/core/SwapChain.cpp

@@ -189,11 +189,16 @@ namespace Copium
     InitializeFramebuffers();
   }
 
-  int SwapChain::GetFlightIndex() const 
+  int SwapChain::GetFlightIndex() const
   {
     return flightIndex;
   }
 
+  int SwapChain::GetImageCount() const
+  {
+    return images.size();
+  }
+
   void SwapChain::Initialize()
   {
     SwapChainSupportDetails swapChainSupport{Vulkan::GetWindow().GetSurface(), Vulkan::GetDevice().GetPhysicalDevice()};

CopiumEngine/src/copium/core/SwapChain.h

@@ -59,6 +59,7 @@ namespace Copium
     void Recreate();
 
     int GetFlightIndex() const;
+    int GetImageCount() const;
 
   private:
     void Initialize();

CopiumEngine/src/copium/core/Vulkan.cpp

@@ -13,6 +13,7 @@ namespace Copium
   std::unique_ptr<Window> Vulkan::window;
   std::unique_ptr<Device> Vulkan::device;
   std::unique_ptr<SwapChain> Vulkan::swapChain;
+  std::unique_ptr<ImGuiInstance> Vulkan::imGuiInstance;
   AssetHandle Vulkan::emptyTexture2D;
 
   void Vulkan::Initialize()
@@ -21,6 +22,7 @@ namespace Copium
     window = std::make_unique<Window>("Copium Engine", 1440, 810, WindowMode::Windowed);
     device = std::make_unique<Device>();
     swapChain = std::make_unique<SwapChain>();
+    imGuiInstance = std::make_unique<ImGuiInstance>();
 
     AssetManager::RegisterAssetType<Texture2D>("Texture2D");
     AssetManager::RegisterAssetType<ColorAttachment>("RenderTexture");
@@ -39,6 +41,7 @@ namespace Copium
     AssetManager::UnloadAsset(emptyTexture2D);
     AssetManager::UnregisterAssetDir("assets/");
     AssetManager::Cleanup();
+    imGuiInstance.reset();
     swapChain.reset();
     device.reset();
     window.reset();
@@ -65,6 +68,11 @@ namespace Copium
     return *swapChain;
   }
 
+  ImGuiInstance& Vulkan::GetImGuiInstance()
+  {
+    return *imGuiInstance;
+  }
+
   AssetHandle Vulkan::GetEmptyTexture2D()
   {
     return emptyTexture2D;

CopiumEngine/src/copium/core/Vulkan.h

@@ -4,6 +4,7 @@
 #include "copium/core/Instance.h"
 #include "copium/core/SwapChain.h"
 #include "copium/core/Window.h"
+#include "copium/core/ImGuiInstance.h"
 #include "copium/util/Common.h"
 
 #include <memory>
@@ -18,6 +19,7 @@ namespace Copium
     static std::unique_ptr<Window> window;
     static std::unique_ptr<Device> device;
     static std::unique_ptr<SwapChain> swapChain;
+    static std::unique_ptr<ImGuiInstance> imGuiInstance;
 
     static AssetHandle emptyTexture2D;
   public:
@@ -27,6 +29,7 @@ namespace Copium
     static Window& GetWindow();
     static Device& GetDevice();
     static SwapChain& GetSwapChain();
+    static ImGuiInstance& GetImGuiInstance();
     static bool Valid();
     static AssetHandle GetEmptyTexture2D();
   };

CopiumEngine/src/copium/pipeline/DescriptorPool.cpp

@@ -47,4 +47,9 @@ namespace Copium
   {
     vkFreeDescriptorSets(Vulkan::GetDevice(), descriptorPool, descriptorSets.size(), descriptorSets.data());
   }
+
+  DescriptorPool::operator VkDescriptorPool() const
+  {
+    return descriptorPool;
+  }
 }

CopiumEngine/src/copium/pipeline/DescriptorPool.h

@@ -18,5 +18,7 @@ namespace Copium
 
     std::vector<VkDescriptorSet> AllocateDescriptorSets(VkDescriptorSetLayout descriptorSetLayout);
     void FreeDescriptorSets(const std::vector<VkDescriptorSet>& descriptorSets);
+
+    operator VkDescriptorPool() const;
   };
 }