font_book.hpp

// Copyright Take Vos 2020-2021.
// 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 "grapheme.hpp"
#include "font.hpp"
#include "font_family_id.hpp"
#include "font_grapheme_id.hpp"
#include "font_glyph_ids.hpp"
#include "elusive_icon.hpp"
#include "ttauri_icon.hpp"
#include "../URL.hpp"
#include "../alignment.hpp"
#include "../subsystem.hpp"
#include <limits>
#include <array>
#include <new>
#include <atomic>
 
namespace tt {
 
class font_book {
public:
    font_book(std::vector<URL> const &font_directories);
 
    font &register_font(URL url, bool post_process = true);
 
    void register_elusive_icon_font(URL url)
    {
        _elusive_icon_font = &register_font(url, false);
    }
 
    void register_ttauri_icon_font(URL url)
    {
        _ttauri_icon_font = &register_font(url, false);
    }
 
    void post_process() noexcept;
 
    [[nodiscard]] font_family_id find_family(std::string_view family_name) const noexcept;
 
    [[nodiscard]] font_family_id register_family(std::string_view family_name) noexcept;
 
    [[nodiscard]] font const &find_font(font_family_id family_id, font_variant variant) const noexcept;
 
    [[nodiscard]] font const &find_font(font_family_id family_id, font_weight weight, bool italic) const noexcept;
 
    [[nodiscard]] font const &find_font(std::string_view family_name, font_weight weight, bool italic) const noexcept;
 
    [[nodiscard]] font_glyph_ids find_glyph(font const &font, grapheme grapheme) const noexcept;
 
    [[nodiscard]] font_glyph_ids find_glyph(elusive_icon rhs) const noexcept
    {
        tt_axiom(_elusive_icon_font);
        return _elusive_icon_font->find_glyph(grapheme{static_cast<char32_t>(rhs)});
    }
 
    [[nodiscard]] font_glyph_ids find_glyph(ttauri_icon rhs) const noexcept
    {
        tt_axiom(_ttauri_icon_font);
        return _ttauri_icon_font->find_glyph(grapheme{static_cast<char32_t>(rhs)});
    }
 
private:
    font const *_elusive_icon_font = nullptr;
    font const *_ttauri_icon_font = nullptr;
 
    std::unordered_map<std::string, font_family_id> family_names;
 
    std::unordered_map<std::string, std::string> family_name_fallback_chain;
 
    std::vector<std::array<font const *, font_variant::max()>> font_variants;
 
    std::vector<std::unique_ptr<font>> _fonts;
    std::vector<tt::font *> _font_ptrs;
 
    mutable std::unordered_map<std::string, font_family_id> family_name_cache;
 
    mutable std::unordered_map<font_grapheme_id, font_glyph_ids> glyph_cache;
 
    [[nodiscard]] std::vector<tt::font *> make_fallback_chain(font_weight weight, bool italic) noexcept;
 
    // void morph_glyphs(glyph_array &glyphs) const noexcept;
 
    // void atlas_lookup(glyph &glyph) noexcept;
 
    // void atlas_lookup(glyph_array &glyphs) noexcept;
 
    // void kern_glyphs(glyph_array &glyphs) const noexcept;
 
    [[nodiscard]] std::string const &find_fallback_family_name(std::string const &name) const noexcept;
 
    void create_family_name_fallback_chain() noexcept;
};
 
} // namespace tt