gfx_pipeline_image_vulkan.hpp

// Copyright Take Vos 2019, 2021.
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at https://www.boost.org/LICENSE_1_0.txt)
 
#pragma once
 
#include "gfx_pipeline_vulkan.hpp"
#include "../container/module.hpp"
#include "../image/module.hpp"
#include "../codec/codec.hpp"
#include "../macros.hpp"
#include <vma/vk_mem_alloc.h>
 
namespace hi { inline namespace v1 {

class gfx_pipeline_image : public gfx_pipeline {
public:
    struct alignas(16) vertex {
        sfloat_rgba32 position;

        sfloat_rgba32 clipping_rectangle;

        sfloat_rgba32 atlas_position;
 
        vertex(sfloat_rgba32 position, sfloat_rgba32 clipping_rectangle, sfloat_rgba32 atlas_position) noexcept :
            position(position), clipping_rectangle(clipping_rectangle), atlas_position(atlas_position)
        {
        }
 
        static vk::VertexInputBindingDescription inputBindingDescription()
        {
            return {0, sizeof(vertex), vk::VertexInputRate::eVertex};
        }
 
        static std::vector<vk::VertexInputAttributeDescription> inputAttributeDescriptions()
        {
            return {
                {0, 0, vk::Format::eR32G32B32A32Sfloat, offsetof(vertex, position)},
                {1, 0, vk::Format::eR32G32B32A32Sfloat, offsetof(vertex, clipping_rectangle)},
                {2, 0, vk::Format::eR32G32B32A32Sfloat, offsetof(vertex, atlas_position)},
            };
        }
    };
 
    struct push_constants {
        sfloat_rg32 windowExtent = extent2{0.0, 0.0};
        sfloat_rg32 viewportScale = scale2{0.0, 0.0};
        sfloat_rg32 atlasExtent = extent2{0.0, 0.0};
        sfloat_rg32 atlasScale = scale2{0.0, 0.0};
 
        static std::vector<vk::PushConstantRange> pushConstantRanges()
        {
            return {{vk::ShaderStageFlagBits::eVertex | vk::ShaderStageFlagBits::eFragment, 0, sizeof(push_constants)}};
        }
    };
 
    struct texture_map {
        vk::Image image;
        VmaAllocation allocation = {};
        vk::ImageView view;
        hi::pixmap_span<sfloat_rgba16> pixmap;
        vk::ImageLayout layout = vk::ImageLayout::eUndefined;
 
        void transitionLayout(const gfx_device& device, vk::Format format, vk::ImageLayout nextLayout);
    };

    struct paged_image {
        enum class state_type { uninitialized, drawing, uploaded };
 
        constexpr static std::size_t page_size = 62; // 64x64 including a 1 pixel border.
 
        mutable std::atomic<state_type> state = state_type::uninitialized;
        gfx_device *device = nullptr;
        std::size_t width;
        std::size_t height;
        std::vector<std::size_t> pages;
 
        ~paged_image();
        constexpr paged_image() noexcept = default;
        paged_image(paged_image&& other) noexcept;
        paged_image& operator=(paged_image&& other) noexcept;
        paged_image(paged_image const& other) = delete;
        paged_image& operator=(paged_image const& other) = delete;
 
        paged_image(gfx_surface const *surface, std::size_t width, std::size_t height) noexcept;
        paged_image(gfx_surface const *surface, pixmap_span<sfloat_rgba16 const> image) noexcept;
        paged_image(gfx_surface const *surface, pixmap<sfloat_rgba16> const& image) noexcept :
            paged_image(surface, pixmap_span<sfloat_rgba16 const>{image})
        {
        }
 
        paged_image(gfx_surface const *surface, png const& image) noexcept;
 
        [[nodiscard]] constexpr explicit operator bool() const noexcept
        {
            return device != nullptr;
        }
 
        [[nodiscard]] constexpr extent2 size() const noexcept
        {
            return extent2{narrow_cast<float>(width), narrow_cast<float>(height)};
        }
 
        [[nodiscard]] constexpr std::pair<std::size_t, std::size_t> size_in_int_pages() const noexcept
        {
            hilet num_columns = (width + page_size - 1) / page_size;
            hilet num_rows = (height + page_size - 1) / page_size;
            return {num_columns, num_rows};
        }
 
        [[nodiscard]] constexpr extent2 size_in_float_pages() const noexcept
        {
            constexpr auto page_size_ = f32x4{narrow_cast<float>(page_size), narrow_cast<float>(page_size), 1.0f, 1.0f};
            auto size = f32x4{narrow_cast<float>(width), narrow_cast<float>(height)};
            return extent2{size / page_size_};
        }

        void upload(pixmap_span<sfloat_rgba16 const> image) noexcept;

        void upload(png const& image) noexcept;
    };
 
    struct device_shared {
        constexpr static std::size_t atlas_num_pages_per_axis = 8;
        constexpr static std::size_t atlas_num_pages_per_image = atlas_num_pages_per_axis * atlas_num_pages_per_axis;
        constexpr static std::size_t atlas_image_axis_size = atlas_num_pages_per_axis * (paged_image::page_size + 2);
        constexpr static std::size_t atlas_maximum_num_images = 64;
        constexpr static std::size_t staging_image_width = 1024;
        constexpr static std::size_t staging_image_height = 1024;
 
        gfx_device const& device;
 
        vk::ShaderModule vertex_shader_module;
        vk::ShaderModule fragment_shader_module;
        std::vector<vk::PipelineShaderStageCreateInfo> shader_stages;
 
        texture_map staging_texture;
        std::vector<texture_map> atlas_textures;
 
        std::array<vk::DescriptorImageInfo, atlas_maximum_num_images> atlas_descriptor_image_infos;
        vk::Sampler atlas_sampler;
        vk::DescriptorImageInfo atlas_sampler_descriptor_image_info;
 
        device_shared(gfx_device const& device);
        ~device_shared();
 
        device_shared(device_shared const&) = delete;
        device_shared& operator=(device_shared const&) = delete;
        device_shared(device_shared&&) = delete;
        device_shared& operator=(device_shared&&) = delete;

        void destroy(gfx_device const *vulkanDevice);

        std::vector<std::size_t> allocate_pages(std::size_t num_pages) noexcept;

        void free_pages(std::vector<std::size_t> const& pages) noexcept;
 
        void draw_in_command_buffer(vk::CommandBuffer const& commandBuffer);

        hi::pixmap_span<sfloat_rgba16> get_staging_pixmap();

        void prepare_atlas_for_rendering();

        void place_vertices(
            vector_span<vertex>& vertices,
            aarectangle const& clipping_rectangle,
            quad const& box,
            paged_image const& image) noexcept;
 
    private:
        std::vector<std::size_t> _atlas_free_pages;

        hi::pixmap_span<sfloat_rgba16> get_staging_pixmap(std::size_t width, std::size_t height)
        {
            return get_staging_pixmap().subimage(0, 0, width, height);
        }

        void make_staging_border_transparent(aarectangle border_rectangle) noexcept;

        void clear_staging_between_border_and_upload(aarectangle border_rectangle, aarectangle upload_rectangle) noexcept;

        void prepare_staging_for_upload(paged_image const& image) noexcept;

        void update_atlas_with_staging_pixmap(paged_image const& image) noexcept;
 
        void build_shaders();
        void teardown_shaders(gfx_device const *device);
        void add_atlas_image();
        void build_atlas();
        void teardown_atlas(gfx_device const *device);
 
        friend paged_image;
    };
 
    vector_span<vertex> vertexBufferData;
 
    ~gfx_pipeline_image() = default;
    gfx_pipeline_image(const gfx_pipeline_image&) = delete;
    gfx_pipeline_image& operator=(const gfx_pipeline_image&) = delete;
    gfx_pipeline_image(gfx_pipeline_image&&) = delete;
    gfx_pipeline_image& operator=(gfx_pipeline_image&&) = delete;
 
    gfx_pipeline_image(gfx_surface *surface) : gfx_pipeline(surface) {}
 
    void draw_in_command_buffer(vk::CommandBuffer commandBuffer, draw_context const& context) override;
 
private:
    push_constants pushConstants;
    int numberOfAtlasImagesInDescriptor = 0;
 
    vk::Buffer vertexBuffer;
    VmaAllocation vertexBufferAllocation;
 
    [[nodiscard]] std::vector<vk::PipelineShaderStageCreateInfo> createShaderStages() const override;
    [[nodiscard]] std::vector<vk::DescriptorSetLayoutBinding> createDescriptorSetLayoutBindings() const override;
    [[nodiscard]] std::vector<vk::WriteDescriptorSet> createWriteDescriptorSet() const override;
    [[nodiscard]] size_t getDescriptorSetVersion() const override;
    [[nodiscard]] std::vector<vk::PushConstantRange> createPushConstantRanges() const override;
    [[nodiscard]] vk::VertexInputBindingDescription createVertexInputBindingDescription() const override;
    [[nodiscard]] std::vector<vk::VertexInputAttributeDescription> createVertexInputAttributeDescriptions() const override;
 
private:
    void build_vertex_buffers() override;
    void teardown_vertex_buffers() override;
};
 
}} // namespace hi::v1