Method ShapeSingleTextLine

libs/drape/texture_manager.cpp:496–562

}

text::TextMetrics TextureManager::ShapeSingleTextLine(
    float fontPixelHeight, std::string_view utf8, TGlyphsBuffer * glyphRegions,
    localisation::LanguageIndex const textLanguageIndex)  // TODO(AB): Better name?
{
  ASSERT(!utf8.empty(), ());
  std::vector<ref_ptr<Texture::ResourceInfo>> resourcesInfo;
  bool hasNewResources = false;
  hb_language_t lang;

  if (textLanguageIndex == localisation::kUnsupportedLanguageIndex)
    lang = m_mapLang;
  else
  {
    localisation::LanguageCode const languageCode = localisation::ConvertLanguageIndexToLanguageCode(textLanguageIndex);
    lang = hb_language_from_string(languageCode.data(), static_cast<int>(languageCode.size()));
  }

  // TODO(AB): Is this mutex too slow?
  std::lock_guard lock(m_calcGlyphsMutex);

  auto textMetrics = m_glyphManager->ShapeText(utf8, fontPixelHeight, lang);

  auto const & glyphs = textMetrics.m_glyphs;

  size_t const hybridGroupIndex = FindHybridGlyphsGroup(glyphs);
  ASSERT(hybridGroupIndex != GetInvalidGlyphGroup(), ());
  GlyphGroup & group = m_glyphGroups[hybridGroupIndex];

  // Mark used glyphs.
  for (auto const & glyph : glyphs)
    group.m_glyphKeys.insert(glyph.m_key);

  if (!group.m_texture)
    group.m_texture = AllocateGlyphTexture();

  if (glyphRegions)
    resourcesInfo.reserve(glyphs.size());

  for (auto const & glyph : glyphs)
  {
    bool newResource = false;
    auto fontTexture = static_cast<FontTexture *>(group.m_texture.get())->MapResource(glyph.m_key, newResource);
    hasNewResources |= newResource;

    if (glyphRegions)
      resourcesInfo.emplace_back(fontTexture);
  }

  if (glyphRegions)
  {
    glyphRegions->reserve(resourcesInfo.size());
    for (auto const & info : resourcesInfo)
    {
      GlyphRegion reg;
      reg.SetResourceInfo(info);
      reg.SetTexture(group.m_texture);
      ASSERT(reg.IsValid(), ());