AttributedGlyph.hpp

// Copyright 2020 Pokitec
// All rights reserved.
 
#pragma once
 
#include "TTauri/Text/FontGlyphIDs.hpp"
#include "TTauri/Text/AttributedGrapheme.hpp"
#include "TTauri/Text/GlyphMetrics.hpp"
#include "TTauri/Foundation/mat.hpp"
 
namespace tt {
 
struct AttributedGlyph {
    FontGlyphIDs glyphs;
 
    ssize_t logicalIndex;
 
    GlyphMetrics metrics;
 
    vec position;
 
    int8_t graphemeCount;
 
    GeneralCharacterClass charClass;
 
    TextStyle style;
 
    AttributedGlyph(AttributedGrapheme const &attr_grapheme, AttributedGlyph const *next_attr_glyph=nullptr) noexcept;
 
    AttributedGlyph(AttributedGlyph const &other) = default;
    AttributedGlyph(AttributedGlyph &&other) noexcept = default;
    AttributedGlyph &operator=(AttributedGlyph const &other) = default;
    AttributedGlyph &operator=(AttributedGlyph &&other) noexcept = default;
    ~AttributedGlyph() = default;
 
    [[nodiscard]] bool containsLogicalIndex(ssize_t index) const noexcept {
        ttlet first = logicalIndex;
        ttlet last = first + graphemeCount;
        return index >= first && index < last;
    }
 
    [[nodiscard]] bool isLetter() const noexcept { return charClass == GeneralCharacterClass::Letter; }
    [[nodiscard]] bool isDigit() const noexcept { return charClass == GeneralCharacterClass::Digit; }
    [[nodiscard]] bool isWord() const noexcept { return isLetter() || isDigit(); }
    [[nodiscard]] bool isWhiteSpace() const noexcept { return charClass == GeneralCharacterClass::WhiteSpace; }
    [[nodiscard]] bool isParagraphSeparator() const noexcept { return charClass == GeneralCharacterClass::ParagraphSeparator; }
    [[nodiscard]] bool isVisible() const noexcept { return isWord() || charClass == GeneralCharacterClass::Unknown; }
    
    [[nodiscard]] int selectionWordClusterID() const noexcept {
        switch (charClass) {
        case GeneralCharacterClass::ParagraphSeparator: return 0;
        case GeneralCharacterClass::Digit:
        case GeneralCharacterClass::Letter: return 1;
        case GeneralCharacterClass::Unknown: return 2;
        case GeneralCharacterClass::WhiteSpace: return 3;
        default: tt_no_default;
        }
    }
 
    [[nodiscard]] aarect boundingBox(float border) const noexcept {
        return mat::T2(position.xyz0()) * expand(metrics.boundingBox, border * style.scaled_size());
    }
 
    [[nodiscard]] ssize_t relativeIndexAtCoordinate(vec coordinate) const noexcept {
        ttlet relativePositionInGlyph = (coordinate.x() - position.x()) / metrics.advance.x();
        ttlet relativePositionPerGrapheme = relativePositionInGlyph * numeric_cast<float>(graphemeCount);
        return numeric_cast<ssize_t>(std::round(relativePositionPerGrapheme));
    }
 
    [[nodiscard]] Path get_path() const noexcept;
};
 
}