add support for RTL text layout (33c442ca) · Commits · github_fork / Clip

core/graphics/text.h

+9 −0

Original line number	Diff line number	Diff line
		@@ -43,6 +43,15 @@ Status drawTextLabel(
		const TextStyle& text_style,
		Layer* layer);

		Status drawTextLabel(
		const std::string& text,
		const Point& position,
		HAlign align_x,
		VAlign align_y,
		double rotate,
		const TextStyle& text_style,
		Layer* layer);

		Status drawTextLabel(
		const std::string& text,
		const Point& position,

core/graphics/text_layout.cc

+34 −15

Original line number	Diff line number	Diff line
		@@ -29,6 +29,7 @@ Status text_layout_hspan(
		std::vector<GlyphInfo> glyph_list;
		auto shaping_rc = text_shape_with_font_fallback(
		text,
		text_direction,
		font_info,
		font_size,
		dpi,
		@@ -38,15 +39,22 @@ Status text_layout_hspan(
		return shaping_rc;
		}

		double line_length = 0.0f;
		double line_top = 0.0f;
		double line_bottom = 0.0f;
		double span_length = 0.0;
		double span_top = 0.0;
		double span_bottom = 0.0;
		for (const auto& gi : glyph_list) {
		GlyphPlacement gp = {
		.codepoint = gi.codepoint,
		.x = line_length,
		.y = 0
		};
		GlyphPlacement gp;
		gp.codepoint = gi.codepoint;
		gp.y = 0;

		switch (text_direction) {
		case TextDirection::LTR:
		gp.x = span_length;
		break;
		case TextDirection::RTL:
		gp.x = -span_length - gi.advance_x;
		break;
		}

		GlyphSpan span;
		span.font = gi.font;
		@@ -57,16 +65,27 @@ Status text_layout_hspan(
		glyph_spans->emplace_back(span);
		}

		line_length += gi.advance_x;
		line_top = std::min(-gi.metrics_ascender, line_top);
		line_bottom = std::max(-gi.metrics_descender, line_bottom);
		span_length += gi.advance_x;
		span_top = std::min(-gi.metrics_ascender, span_top);
		span_bottom = std::max(-gi.metrics_descender, span_bottom);
		}


		double span_left = 0.0;
		switch (text_direction) {
		case TextDirection::LTR:
		span_left = 0;
		break;
		case TextDirection::RTL:
		span_left = -span_length;
		break;
		}

		*bbox = Rectangle(
		0,
		line_top,
		line_length,
		line_bottom - line_top);
		span_left,
		span_top,
		span_length,
		span_bottom - span_top);

		return OK;
		}

core/graphics/text_shaper.cc

+11 −3

Original line number	Diff line number	Diff line
		@@ -23,6 +23,7 @@ namespace text {

		Status text_shape(
		const std::string& text,
		TextDirection text_direction,
		FontRef font,
		double font_size,
		double dpi,
		@@ -40,8 +41,14 @@ Status text_shape(
		auto hb_font = hb_ft_font_create_referenced(ft_font);

		hb_buffer_reset(hb_buf);
		switch (text_direction) {
		case TextDirection::LTR:
		hb_buffer_set_direction(hb_buf, HB_DIRECTION_LTR);
		hb_buffer_set_script(hb_buf, HB_SCRIPT_LATIN);
		break;
		case TextDirection::RTL:
		hb_buffer_set_direction(hb_buf, HB_DIRECTION_RTL);
		break;
		}

		hb_buffer_add_utf8(hb_buf, text.data(), text.size(), 0, text.size());
		hb_shape(hb_font, hb_buf, NULL, 0);
		@@ -67,6 +74,7 @@ Status text_shape(

		Status text_shape_with_font_fallback(
		const std::string& text,
		TextDirection dir,
		const FontInfo& font_info,
		double font_size,
		double dpi,
		@@ -87,7 +95,7 @@ Status text_shape_with_font_fallback(
		for (const auto& font : font_info.fonts) {
		grapheme_glyphs.clear();

		auto rc = text_shape(grapheme, font, font_size, dpi, &grapheme_glyphs);
		auto rc = text_shape(grapheme, dir, font, font_size, dpi, &grapheme_glyphs);
		if (rc != OK) {
		return rc;
		}

core/graphics/text_shaper.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -38,6 +38,7 @@ struct GlyphInfo {

		Status text_shape(
		const std::string& text,
		TextDirection text_direction,
		FontRef font,
		double font_size,
		double dpi,
		@@ -45,6 +46,7 @@ Status text_shape(

		Status text_shape_with_font_fallback(
		const std::string& text,
		TextDirection text_direction,
		const FontInfo& font_info,
		double font_size,
		double dpi,

tests/unit/test_graphics_text_align.cc

+34 −17

Original line number	Diff line number	Diff line
		@@ -27,48 +27,65 @@ void draw_test(
		const FontInfo& font,
		uint32_t x,
		uint32_t y,
		TextDirection dir,
		HAlign ax,
		VAlign ay) {
		TextStyle ts;
		ts.font = font;
		ts.font_size = from_unit(64);
		ts.font_size = from_unit(32);
		ts.color = Color::fromRGB(0,0,0);
		ts.direction = dir;

		StrokeStyle ss;
		ss.line_width = from_unit(1);

		strokeLine(l, Point(x - 10, y), Point(x + 10, y), ss);
		strokeLine(l, Point(x, y - 10), Point(x, y + 10), ss);
		drawTextLabel("Fnord!", Point(x, y), ax, ay, ts, l);
		drawTextLabel("Hello תל אביב !", Point(x, y), ax, ay, 0, ts, l);
		}

		void draw_test(Layer* layer, const FontInfo& font) {
		draw_test(layer, font, 100 * 2, 100 * 2, HAlign::LEFT, VAlign::TOP);
		draw_test(layer, font, 400 * 2, 100 * 2, HAlign::CENTER, VAlign::TOP);
		draw_test(layer, font, 700 * 2, 100 * 2, HAlign::RIGHT, VAlign::TOP);
		draw_test(layer, font, 100 * 2, 100 * 2, TextDirection::LTR, HAlign::LEFT, VAlign::TOP);
		draw_test(layer, font, 400 * 2, 100 * 2, TextDirection::LTR, HAlign::CENTER, VAlign::TOP);
		draw_test(layer, font, 700 * 2, 100 * 2, TextDirection::LTR, HAlign::RIGHT, VAlign::TOP);

		draw_test(layer, font, 100 * 2, 200 * 2, HAlign::LEFT, VAlign::CENTER);
		draw_test(layer, font, 400 * 2, 200 * 2, HAlign::CENTER, VAlign::CENTER);
		draw_test(layer, font, 700 * 2, 200 * 2, HAlign::RIGHT, VAlign::CENTER);
		draw_test(layer, font, 100 * 2, 200 * 2, TextDirection::LTR, HAlign::LEFT, VAlign::CENTER);
		draw_test(layer, font, 400 * 2, 200 * 2, TextDirection::LTR, HAlign::CENTER, VAlign::CENTER);
		draw_test(layer, font, 700 * 2, 200 * 2, TextDirection::LTR, HAlign::RIGHT, VAlign::CENTER);

		draw_test(layer, font, 100 * 2, 300 * 2, TextDirection::LTR, HAlign::LEFT, VAlign::BOTTOM);
		draw_test(layer, font, 400 * 2, 300 * 2, TextDirection::LTR, HAlign::CENTER, VAlign::BOTTOM);
		draw_test(layer, font, 700 * 2, 300 * 2, TextDirection::LTR, HAlign::RIGHT, VAlign::BOTTOM);

		draw_test(layer, font, 100 * 2, 400 * 2, TextDirection::RTL, HAlign::LEFT, VAlign::TOP);
		draw_test(layer, font, 400 * 2, 400 * 2, TextDirection::RTL, HAlign::CENTER, VAlign::TOP);
		draw_test(layer, font, 700 * 2, 400 * 2, TextDirection::RTL, HAlign::RIGHT, VAlign::TOP);

		draw_test(layer, font, 100 * 2, 500 * 2, TextDirection::RTL, HAlign::LEFT, VAlign::CENTER);
		draw_test(layer, font, 400 * 2, 500 * 2, TextDirection::RTL, HAlign::CENTER, VAlign::CENTER);
		draw_test(layer, font, 700 * 2, 500 * 2, TextDirection::RTL, HAlign::RIGHT, VAlign::CENTER);

		draw_test(layer, font, 100 * 2, 600 * 2, TextDirection::RTL, HAlign::LEFT, VAlign::BOTTOM);
		draw_test(layer, font, 400 * 2, 600 * 2, TextDirection::RTL, HAlign::CENTER, VAlign::BOTTOM);
		draw_test(layer, font, 700 * 2, 600 * 2, TextDirection::RTL, HAlign::RIGHT, VAlign::BOTTOM);

		draw_test(layer, font, 100 * 2, 300 * 2, HAlign::LEFT, VAlign::BOTTOM);
		draw_test(layer, font, 400 * 2, 300 * 2, HAlign::CENTER, VAlign::BOTTOM);
		draw_test(layer, font, 700 * 2, 300 * 2, HAlign::RIGHT, VAlign::BOTTOM);
		}

		int main(int argc, char** argv) {
		FontRef font_ref;
		EXPECT_OK(font_load("/usr/share/fonts/msttcore/comic.ttf", &font_ref));
		FontRef font_ref1;
		EXPECT_OK(font_load("/usr/share/fonts/msttcore/arial.ttf", &font_ref1));

		FontRef font_ref2;
		EXPECT_OK(font_load("/usr/share/fonts/msttcore/comic.ttf", &font_ref2));

		FontInfo font;
		font.font_family_css = "'Comic Sans MS'";
		font.fonts = {font_ref};
		font.fonts = {font_ref2, font_ref1};

		{
		LayerRef layer;
		auto rc = layer_bind_svg(
		1600,
		1000,
		1400,
		96,
		from_unit(12),
		Color::fromRGB(1.0, 1.0, 1.0),
		@@ -86,7 +103,7 @@ int main(int argc, char** argv) {
		LayerRef layer;
		auto rc = layer_bind_png(
		1600,
		1000,
		1400,
		96,
		from_unit(12),
		Color::fromRGB(1.0, 1.0, 1.0),

Admin message