/* * Copyright (c) 2018-2020, Andreas Kling * Copyright (c) 2021, sin-ack * * SPDX-License-Identifier: BSD-2-Clause */ #include "TextLayout.h" #include #include #include namespace Gfx { void for_each_glyph_position(FloatPoint baseline_start, Utf8View string, Gfx::Font const& font, Function callback, Optional width) { hb_buffer_t* buffer = hb_buffer_create(); ScopeGuard destroy_buffer = [&]() { hb_buffer_destroy(buffer); }; hb_buffer_add_utf8(buffer, reinterpret_cast(string.bytes()), string.byte_length(), 0, -1); hb_buffer_guess_segment_properties(buffer); u32 glyph_count; auto* glyph_info = hb_buffer_get_glyph_infos(buffer, &glyph_count); Vector const input_glyph_info({ glyph_info, glyph_count }); if (input_glyph_info.is_empty()) return; auto* hb_font = font.harfbuzz_font(); hb_shape(hb_font, buffer, nullptr, 0); glyph_info = hb_buffer_get_glyph_infos(buffer, &glyph_count); auto* positions = hb_buffer_get_glyph_positions(buffer, &glyph_count); FloatPoint point = baseline_start; for (size_t i = 0; i < glyph_count; ++i) { auto position = point - FloatPoint { 0, font.pixel_metrics().ascent } + FloatPoint { positions[i].x_offset, positions[i].y_offset } / text_shaping_resolution; callback(DrawGlyph { .position = position, .glyph_id = glyph_info[i].codepoint, }); point += FloatPoint { positions[i].x_advance, positions[i].y_advance } / text_shaping_resolution; } if (width.has_value()) *width = point.x(); } float measure_text_width(Utf8View const& string, Gfx::Font const& font) { float width = 0; for_each_glyph_position({}, string, font, [&](DrawGlyph const&) {}, width); return width; } }