bitmap.h

#pragma once
 
#include <glm/vec2.hpp>
 
#include <cstdint>
#include <filesystem>
#include <span>
#include <string>
#include <utility>
#include <vector>
 
namespace pixelbullet
{
class Filesystem;
class VirtualPath;

class Bitmap
{
public:
    static constexpr std::uint32_t bytes_per_pixel = 4u;
 
    Bitmap() = default;
 
    Bitmap(const Filesystem& filesystem, const VirtualPath& asset_path)
    {
        static_cast<void>(load(filesystem, asset_path));
    }
 
    explicit Bitmap(const glm::uvec2& size)
    {
        static_cast<void>(resize(size));
    }
 
    Bitmap(const glm::uvec2& size, std::vector<std::uint8_t> pixels)
    {
        static_cast<void>(replace_rgba8(size, std::move(pixels)));
    }
 
    ~Bitmap() = default;
 
    [[nodiscard]] bool load(const Filesystem& filesystem, const VirtualPath& asset_path);
 
    [[nodiscard]] bool write(const std::filesystem::path& path) const;
 
    explicit operator bool() const noexcept
    {
        return has_valid_storage();
    }
 
    [[nodiscard]] std::size_t byte_length() const noexcept
    {
        return data_.size();
    }
 
    void clear() noexcept;
 
    [[nodiscard]] const std::string& filename() const noexcept
    {
        return filename_;
    }
 
    [[nodiscard]] const std::vector<std::uint8_t>& data() const noexcept
    {
        return data_;
    }
 
    [[nodiscard]] std::span<std::uint8_t> mutable_data() noexcept
    {
        return data_;
    }
 
    [[nodiscard]] const glm::uvec2& size() const noexcept
    {
        return size_;
    }
 
    [[nodiscard]] bool replace_rgba8(const glm::uvec2& size, std::vector<std::uint8_t> pixels);
 
    [[nodiscard]] bool has_valid_storage() const noexcept;
 
private:
    [[nodiscard]] static bool checked_byte_length(const glm::uvec2& size, std::size_t* byte_length) noexcept;
 
    [[nodiscard]] bool resize(const glm::uvec2& size);
 
    void set_filename(std::string filename)
    {
        filename_ = std::move(filename);
    }
 
private:
    std::string filename_;
    std::vector<std::uint8_t> data_;
    glm::uvec2 size_{ 0u, 0u };
};
} // namespace pixelbullet