Method Layouter

src/gfx_layout.cpp:129–202

* Create a new layouter. * @param str The string to create the layout for. * @param maxw The maximum width. * @param fontsize The size of font to use. */

 * @param fontsize The size of font to use.
 */
Layouter::Layouter(std::string_view str, int maxw, FontSize fontsize) : string(str)
{
	FontState state(TC_INVALID, fontsize);

	while (true) {
		auto line_length = str.find_first_of('\n');
		auto str_line = str.substr(0, line_length);

		LineCacheItem &line = GetCachedParagraphLayout(str_line, state);
		if (line.layout != nullptr) {
			state = line.state_after;
			line.layout->Reflow();
		} else {
			/* Line is new, layout it */
			FontState old_state = state;

#if defined(WITH_ICU_I18N) && defined(WITH_HARFBUZZ)
			if (line.layout == nullptr) {
				GetLayouter<ICUParagraphLayoutFactory>(line, str_line, state);
				if (line.layout == nullptr) {
					state = std::move(old_state);
				}
			}
#endif

#ifdef WITH_UNISCRIBE
			if (line.layout == nullptr) {
				GetLayouter<UniscribeParagraphLayoutFactory>(line, str_line, state);
				if (line.layout == nullptr) {
					state = std::move(old_state);
				}
			}
#endif

#ifdef WITH_COCOA
			if (line.layout == nullptr) {
				GetLayouter<CoreTextParagraphLayoutFactory>(line, str_line, state);
				if (line.layout == nullptr) {
					state = std::move(old_state);
				}
			}
#endif

			if (line.layout == nullptr) {
				GetLayouter<FallbackParagraphLayoutFactory>(line, str_line, state);
			}
		}

		if (line.cached_width != maxw) {
			/* First run or width has changed, so we need to go through the layouter. Lines are moved into a cache to
			 * be reused if the width is not changed. */
			line.cached_layout.clear();
			line.cached_width = maxw;
			for (;;) {
				auto l = line.layout->NextLine(maxw);
				if (l == nullptr) break;
				line.cached_layout.push_back(std::move(l));
			}