WorldUiRenderer.h

#pragma once
 
#include "Engine/Texture/RuntimeTextureDescriptorLease.h"
 
#include <cstdint>
#include <unordered_map>
#include <vector>
#include <vk_mem_alloc.h>
#include <vulkan/vulkan.h>
 
struct ImGuiContext;
 
namespace Engine::Components
{
    class WidgetComponent;
}  // namespace Engine::Components
 
namespace Engine::Core
{
    class ApplicationContext;
    class AssetManager;
}  // namespace Engine::Core
 
namespace Engine::Rendering
{
    class RenderProcess;

    class WorldUiRenderer
    {
    public:
        WorldUiRenderer() = default;
        WorldUiRenderer(Core::ApplicationContext * context, uint32_t framesInFlight);

        ~WorldUiRenderer();

        WorldUiRenderer( const WorldUiRenderer & ) = delete;

        WorldUiRenderer & operator=( const WorldUiRenderer & ) = delete;
 

        [[nodiscard]] uint32_t registerWidget(
            Components::WidgetComponent &widget
        );

        void unregisterWidget( Components::WidgetComponent & widget );

        void renderWidgets(
            VkCommandBuffer commandBuffer,
            uint32_t frameIndex,
            RenderProcess &renderProcess
        );
 
    private:
        void cleanup();
 
        struct TargetFrame
        {
            VkImage       image         = VK_NULL_HANDLE;
            VmaAllocation allocation    = VK_NULL_HANDLE;
            VkImageView   imageView     = VK_NULL_HANDLE;
            VkImageLayout currentLayout = VK_IMAGE_LAYOUT_UNDEFINED;
        };
 
        struct Target
        {
            Components::WidgetComponent * widget = nullptr;
            Assets::RuntimeTextureDescriptorLease descriptor;
            uint32_t width = 0;
            uint32_t height = 0;
            std::vector<TargetFrame> frames;
            uint64_t loggedDescriptorWriteFrames = 0;
        };
 
        struct RetiredTarget
        {
            Target   target;
            uint32_t framesRemaining = 0;
        };
 
        struct ImGuiTexture
        {
            VkDescriptorSet descriptor = VK_NULL_HANDLE;
            VkImageView imageView = VK_NULL_HANDLE;
            VkSampler sampler = VK_NULL_HANDLE;
        };
 
        Target & ensureTarget(Components::WidgetComponent &widget);
        void createTargetImages( Target & target ) const;
        void destroyTarget( Target & target ) const;
        void retireTarget( Target && target );
        void processRetiredTargets();
        void transitionTargetsToColorAttachment( VkCommandBuffer commandBuffer, uint32_t frameIndex );
        void transitionTargetsToShaderRead( VkCommandBuffer commandBuffer, uint32_t frameIndex );
        void renderTarget(VkCommandBuffer commandBuffer, Target &target, uint32_t frameIndex);
        void prepareWidgetTextures(Components::WidgetComponent &widget);
 
        Core::ApplicationContext * context_ = nullptr;
        ImGuiContext *             imguiContext_ = nullptr;
        VkDescriptorPool           descriptorPool_ = VK_NULL_HANDLE;
        VkSampler                  sampler_ = VK_NULL_HANDLE;
        VkFormat                   format_ = VK_FORMAT_R8G8B8A8_UNORM;
        uint32_t                   framesInFlight_ = 0;
        bool                       initialized_ = false;
 
        std::unordered_map<Components::WidgetComponent *, Target> targets_;
        std::unordered_map<uint32_t, ImGuiTexture> imguiTextures_;
        std::vector<RetiredTarget> retiredTargets_;
    };
}  // namespace Engine::Rendering