aseprite.h

// © Joseph Cameron - MIT License
 
#ifndef GDK_GRAPHICS_EXT_ASEPRITE_H
#define GDK_GRAPHICS_EXT_ASEPRITE_H
 
#include <gdk/graphics/ext/sprite_animation.h>
 
#include <cstddef>
#include <optional>
#include <span>
#include <string>
#include <string_view>
#include <vector>
 
namespace gdk::graphics::ext {
    struct aseprite_frame final {
        int x = 0;
        int y = 0;
        int w = 0;
        int h = 0;
 
        int offsetX = 0;
        int offsetY = 0;
        int sourceWidth = 0;
        int sourceHeight = 0;
 
        int milliseconds = 0;
 
        [[nodiscard]] bool operator==(const aseprite_frame &) const = default;
    };

    enum class aseprite_direction { 
        forward, 
        reverse, 
        ping_pong, 
        ping_pong_reverse 
    };

    struct aseprite_tag final {
        std::string name;
 
        int from = 0;
        int to = 0;
 
        aseprite_direction direction = aseprite_direction::forward;
 
        int repeat = 0;
 
        std::string data;
 
        [[nodiscard]] bool operator==(const aseprite_tag &) const = default;
    };

    struct aseprite_slice final {
        std::string name;
 
        int frame = 0;
 
        int x = 0;
        int y = 0;
        int w = 0;
        int h = 0;
 
        std::optional<std::pair<int, int>> pivot;
 
        [[nodiscard]] bool operator==(const aseprite_slice &) const = default;
    };
 
    struct aseprite_sheet final {
        std::string image;
 
        int width = 0;
        int height = 0;
 
        std::vector<aseprite_frame> frames;
 
        std::vector<aseprite_tag> tags;
 
        std::vector<aseprite_slice> slices;

        [[nodiscard]] const aseprite_tag *tag(std::string_view aName) const;

        [[nodiscard]] const aseprite_slice *slice(std::string_view aName) const;
    };

    constexpr std::size_t MOST_ASEPRITE_FRAMES = 65536;

    [[nodiscard]] aseprite_sheet read_aseprite(std::span<const std::byte> aBytes);

    [[nodiscard]] std::vector<sprite_animation::frame> frames_of(
            const aseprite_sheet &aSheet, 
            const aseprite_tag &aTag);

    [[nodiscard]] std::vector<sprite_animation::frame> frames_of(const aseprite_sheet &aSheet);

    [[nodiscard]] sprite_animation animation_of(const aseprite_sheet &aSheet, std::string_view aTag);

    [[nodiscard]] sprite_animation animation_of(const aseprite_sheet &aSheet);
}
 
#endif