[TextServer] Add function to change font, font size, and OpenType features without invalidating line break points, justification points, or recreating shaped text buffer.

6 files changed, 156 insertions, 40 deletions

diff --git a/scene/gui/label.cpp b/scene/gui/label.cpp
index fab420d593..852aaaab24 100644
--- a/scene/gui/label.cpp
+++ b/scene/gui/label.cpp
@@ -82,9 +82,11 @@ void Label::_shape() {
 	Ref<StyleBox> style = get_theme_stylebox(SNAME("normal"), SNAME("Label"));
 	int width = (get_size().width - style->get_minimum_size().width);
 
-	if (dirty) {
+	if (dirty || font_dirty) {
 		String lang = (!language.is_empty()) ? language : TranslationServer::get_singleton()->get_tool_locale();
-		TS->shaped_text_clear(text_rid);
+		if (dirty) {
+			TS->shaped_text_clear(text_rid);
+		}
 		if (text_direction == Control::TEXT_DIRECTION_INHERITED) {
 			TS->shaped_text_set_direction(text_rid, is_layout_rtl() ? TextServer::DIRECTION_RTL : TextServer::DIRECTION_LTR);
 		} else {
@@ -97,9 +99,17 @@ void Label::_shape() {
 		if (visible_chars >= 0 && visible_chars_behavior == VC_CHARS_BEFORE_SHAPING) {
 			text = text.substr(0, visible_chars);
 		}
-		TS->shaped_text_add_string(text_rid, text, font->get_rids(), font_size, opentype_features, lang);
+		if (dirty) {
+			TS->shaped_text_add_string(text_rid, text, font->get_rids(), font_size, opentype_features, lang);
+		} else {
+			int spans = TS->shaped_get_span_count(text_rid);
+			for (int i = 0; i < spans; i++) {
+				TS->shaped_set_span_update_font(text_rid, i, font->get_rids(), font_size, opentype_features);
+			}
+		}
 		TS->shaped_text_set_bidi_override(text_rid, structured_text_parser(st_parser, st_args, text));
 		dirty = false;
+		font_dirty = false;
 		lines_dirty = true;
 	}
 
@@ -276,7 +286,7 @@ void Label::_notification(int p_what) {
 			RenderingServer::get_singleton()->canvas_item_set_clip(get_canvas_item(), true);
 		}
 
-		if (dirty || lines_dirty) {
+		if (dirty || font_dirty || lines_dirty) {
 			_shape();
 		}
 
@@ -521,7 +531,7 @@ void Label::_notification(int p_what) {
 	}
 
 	if (p_what == NOTIFICATION_THEME_CHANGED) {
-		dirty = true;
+		font_dirty = true;
 		update();
 	}
 	if (p_what == NOTIFICATION_RESIZED) {
@@ -531,7 +541,7 @@ void Label::_notification(int p_what) {
 
 Size2 Label::get_minimum_size() const {
 	// don't want to mutable everything
-	if (dirty || lines_dirty) {
+	if (dirty || font_dirty || lines_dirty) {
 		const_cast<Label *>(this)->_shape();
 	}
 
@@ -555,7 +565,7 @@ int Label::get_line_count() const {
 	if (!is_inside_tree()) {
 		return 1;
 	}
-	if (dirty || lines_dirty) {
+	if (dirty || font_dirty || lines_dirty) {
 		const_cast<Label *>(this)->_shape();
 	}
 
@@ -630,7 +640,7 @@ void Label::set_text_direction(Control::TextDirection p_text_direction) {
 	ERR_FAIL_COND((int)p_text_direction < -1 || (int)p_text_direction > 3);
 	if (text_direction != p_text_direction) {
 		text_direction = p_text_direction;
-		dirty = true;
+		font_dirty = true;
 		update();
 	}
 }
@@ -638,7 +648,7 @@ void Label::set_text_direction(Control::TextDirection p_text_direction) {
 void Label::set_structured_text_bidi_override(Control::StructuredTextParser p_parser) {
 	if (st_parser != p_parser) {
 		st_parser = p_parser;
-		dirty = true;
+		font_dirty = true;
 		update();
 	}
 }
@@ -649,7 +659,7 @@ Control::StructuredTextParser Label::get_structured_text_bidi_override() const {
 
 void Label::set_structured_text_bidi_override_options(Array p_args) {
 	st_args = p_args;
-	dirty = true;
+	font_dirty = true;
 	update();
 }
 
@@ -663,7 +673,7 @@ Control::TextDirection Label::get_text_direction() const {
 
 void Label::clear_opentype_features() {
 	opentype_features.clear();
-	dirty = true;
+	font_dirty = true;
 	update();
 }
 
@@ -671,7 +681,7 @@ void Label::set_opentype_feature(const String &p_name, int p_value) {
 	int32_t tag = TS->name_to_tag(p_name);
 	if (!opentype_features.has(tag) || (int)opentype_features[tag] != p_value) {
 		opentype_features[tag] = p_value;
-		dirty = true;
+		font_dirty = true;
 		update();
 	}
 }
@@ -798,7 +808,7 @@ int Label::get_max_lines_visible() const {
 }
 
 int Label::get_total_character_count() const {
-	if (dirty || lines_dirty) {
+	if (dirty || font_dirty || lines_dirty) {
 		const_cast<Label *>(this)->_shape();
 	}
 
@@ -814,13 +824,13 @@ bool Label::_set(const StringName &p_name, const Variant &p_value) {
 		if (value == -1) {
 			if (opentype_features.has(tag)) {
 				opentype_features.erase(tag);
-				dirty = true;
+				font_dirty = true;
 				update();
 			}
 		} else {
 			if (!opentype_features.has(tag) || (int)opentype_features[tag] != value) {
 				opentype_features[tag] = value;
-				dirty = true;
+				font_dirty = true;
 				update();
 			}
 		}
diff --git a/scene/gui/label.h b/scene/gui/label.h
index 354e9c664d..0b931b3084 100644
--- a/scene/gui/label.h
+++ b/scene/gui/label.h
@@ -73,6 +73,7 @@ private:
 
 	bool lines_dirty = true;
 	bool dirty = true;
+	bool font_dirty = true;
 	RID text_rid;
 	Vector<RID> lines_rid;
 
diff --git a/scene/gui/rich_text_label.cpp b/scene/gui/rich_text_label.cpp
index 151ae2f092..8f4c063c58 100644
--- a/scene/gui/rich_text_label.cpp
+++ b/scene/gui/rich_text_label.cpp
@@ -205,6 +205,49 @@ String RichTextLabel::_letters(int p_num, bool p_capitalize) const {
 	return s;
 }
 
+void RichTextLabel::_update_line_font(ItemFrame *p_frame, int p_line, const Ref<Font> &p_base_font, int p_base_font_size) {
+	ERR_FAIL_COND(p_frame == nullptr);
+	ERR_FAIL_COND(p_line < 0 || p_line >= p_frame->lines.size());
+
+	Line &l = p_frame->lines.write[p_line];
+
+	RID t = l.text_buf->get_rid();
+	int spans = TS->shaped_get_span_count(t);
+	for (int i = 0; i < spans; i++) {
+		ItemText *it = (ItemText *)(uint64_t)TS->shaped_get_span_meta(t, i);
+		if (it) {
+			Ref<Font> font = _find_font(it);
+			if (font.is_null()) {
+				font = p_base_font;
+			}
+			int font_size = _find_font_size(it);
+			if (font_size == -1) {
+				font_size = p_base_font_size;
+			}
+			Dictionary font_ftr = _find_font_features(it);
+			TS->shaped_set_span_update_font(t, i, font->get_rids(), font_size, font_ftr);
+		}
+	}
+
+	Item *it_to = (p_line + 1 < p_frame->lines.size()) ? p_frame->lines[p_line + 1].from : nullptr;
+	for (Item *it = l.from; it && it != it_to; it = _get_next_item(it)) {
+		switch (it->type) {
+			case ITEM_TABLE: {
+				ItemTable *table = static_cast<ItemTable *>(it);
+				for (Item *E : table->subitems) {
+					ERR_CONTINUE(E->type != ITEM_FRAME); // Children should all be frames.
+					ItemFrame *frame = static_cast<ItemFrame *>(E);
+					for (int i = 0; i < frame->lines.size(); i++) {
+						_update_line_font(frame, i, p_base_font, p_base_font_size);
+					}
+				}
+			} break;
+			default:
+				break;
+		}
+	}
+}
+
 void RichTextLabel::_resize_line(ItemFrame *p_frame, int p_line, const Ref<Font> &p_base_font, int p_base_font_size, int p_width) {
 	ERR_FAIL_COND(p_frame == nullptr);
 	ERR_FAIL_COND(p_line < 0 || p_line >= p_frame->lines.size());
@@ -449,7 +492,7 @@ void RichTextLabel::_shape_line(ItemFrame *p_frame, int p_line, const Ref<Font>
 				}
 				remaining_characters -= tx.length();
 
-				l.text_buf->add_string(tx, font, font_size, font_ftr, lang);
+				l.text_buf->add_string(tx, font, font_size, font_ftr, lang, (uint64_t)it);
 				text += tx;
 				l.char_count += tx.length();
 			} break;
@@ -1448,7 +1491,10 @@ void RichTextLabel::_notification(int p_what) {
 			update();
 
 		} break;
-		case NOTIFICATION_THEME_CHANGED:
+		case NOTIFICATION_THEME_CHANGED: {
+			main->first_invalid_font_line = 0; //invalidate ALL
+			update();
+		} break;
 		case NOTIFICATION_ENTER_TREE: {
 			if (!text.is_empty()) {
 				set_text(text);
@@ -1545,6 +1591,10 @@ Control::CursorShape RichTextLabel::get_cursor_shape(const Point2 &p_pos) const
 		return get_default_cursor_shape(); //invalid
 	}
 
+	if (main->first_invalid_font_line < main->lines.size()) {
+		return get_default_cursor_shape(); //invalid
+	}
+
 	if (main->first_resized_line < main->lines.size()) {
 		return get_default_cursor_shape(); //invalid
 	}
@@ -1569,6 +1619,9 @@ void RichTextLabel::gui_input(const Ref<InputEvent> &p_event) {
 		if (main->first_invalid_line < main->lines.size()) {
 			return;
 		}
+		if (main->first_invalid_font_line < main->lines.size()) {
+			return;
+		}
 		if (main->first_resized_line < main->lines.size()) {
 			return;
 		}
@@ -1732,6 +1785,9 @@ void RichTextLabel::gui_input(const Ref<InputEvent> &p_event) {
 		if (main->first_invalid_line < main->lines.size()) {
 			return;
 		}
+		if (main->first_invalid_font_line < main->lines.size()) {
+			return;
+		}
 		if (main->first_resized_line < main->lines.size()) {
 			return;
 		}
@@ -2184,6 +2240,18 @@ bool RichTextLabel::_find_layout_subitem(Item *from, Item *to) {
 
 void RichTextLabel::_validate_line_caches(ItemFrame *p_frame) {
 	if (p_frame->first_invalid_line == p_frame->lines.size()) {
+		Ref<Font> base_font = get_theme_font(SNAME("normal_font"));
+		int base_font_size = get_theme_font_size(SNAME("normal_font_size"));
+
+		// Update fonts.
+		if (p_frame->first_invalid_font_line != p_frame->lines.size()) {
+			for (int i = p_frame->first_invalid_font_line; i < p_frame->lines.size(); i++) {
+				_update_line_font(p_frame, i, base_font, base_font_size);
+			}
+			p_frame->first_resized_line = p_frame->first_invalid_font_line;
+			p_frame->first_invalid_font_line = p_frame->lines.size();
+		}
+
 		if (p_frame->first_resized_line == p_frame->lines.size()) {
 			return;
 		}
@@ -2191,9 +2259,6 @@ void RichTextLabel::_validate_line_caches(ItemFrame *p_frame) {
 		// Resize lines without reshaping.
 		Rect2 text_rect = _get_text_rect();
 
-		Ref<Font> base_font = get_theme_font(SNAME("normal_font"));
-		int base_font_size = get_theme_font_size(SNAME("normal_font_size"));
-
 		for (int i = p_frame->first_resized_line; i < p_frame->lines.size(); i++) {
 			_resize_line(p_frame, i, base_font, base_font_size, text_rect.get_size().width - scroll_w);
 		}
@@ -2237,6 +2302,7 @@ void RichTextLabel::_validate_line_caches(ItemFrame *p_frame) {
 
 	p_frame->first_invalid_line = p_frame->lines.size();
 	p_frame->first_resized_line = p_frame->lines.size();
+	p_frame->first_invalid_font_line = p_frame->lines.size();
 
 	updating_scroll = true;
 	vscroll->set_max(total_height);
@@ -4494,6 +4560,7 @@ RichTextLabel::RichTextLabel() {
 	main->lines.write[0].from = main;
 	main->first_invalid_line = 0;
 	main->first_resized_line = 0;
+	main->first_invalid_font_line = 0;
 	current_frame = main;
 
 	vscroll = memnew(VScrollBar);
diff --git a/scene/gui/rich_text_label.h b/scene/gui/rich_text_label.h
index 70467e7e7c..2b24da4c37 100644
--- a/scene/gui/rich_text_label.h
+++ b/scene/gui/rich_text_label.h
@@ -129,6 +129,7 @@ private:
 
 		Vector<Line> lines;
 		int first_invalid_line = 0;
+		int first_invalid_font_line = 0;
 		int first_resized_line = 0;
 
 		ItemFrame *parent_frame = nullptr;
@@ -414,6 +415,7 @@ private:
 
 	void _shape_line(ItemFrame *p_frame, int p_line, const Ref<Font> &p_base_font, int p_base_font_size, int p_width, int *r_char_offset);
 	void _resize_line(ItemFrame *p_frame, int p_line, const Ref<Font> &p_base_font, int p_base_font_size, int p_width);
+	void _update_line_font(ItemFrame *p_frame, int p_line, const Ref<Font> &p_base_font, int p_base_font_size);
 	int _draw_line(ItemFrame *p_frame, int p_line, const Vector2 &p_ofs, int p_width, const Color &p_base_color, int p_outline_size, const Color &p_outline_color, const Color &p_font_shadow_color, int p_shadow_outline_size, const Point2 &p_shadow_ofs, int &r_processed_glyphs);
 	float _find_click_in_line(ItemFrame *p_frame, int p_line, const Vector2 &p_ofs, int p_width, const Point2i &p_click, ItemFrame **r_click_frame = nullptr, int *r_click_line = nullptr, Item **r_click_item = nullptr, int *r_click_char = nullptr);
 
diff --git a/scene/gui/text_edit.cpp b/scene/gui/text_edit.cpp
index e060d3b901..0ee4a6af4e 100644
--- a/scene/gui/text_edit.cpp
+++ b/scene/gui/text_edit.cpp
@@ -187,29 +187,44 @@ void TextEdit::Text::_calculate_max_line_width() {
 	max_width = width;
 }
 
-void TextEdit::Text::invalidate_cache(int p_line, int p_column, const String &p_ime_text, const Array &p_bidi_override) {
+void TextEdit::Text::invalidate_cache(int p_line, int p_column, bool p_text_changed, const String &p_ime_text, const Array &p_bidi_override) {
 	ERR_FAIL_INDEX(p_line, text.size());
 
 	if (font.is_null() || font_size <= 0) {
 		return; // Not in tree?
 	}
 
-	text.write[p_line].data_buf->clear();
+	if (p_text_changed) {
+		text.write[p_line].data_buf->clear();
+	}
+
 	text.write[p_line].data_buf->set_width(width);
 	text.write[p_line].data_buf->set_direction((TextServer::Direction)direction);
 	text.write[p_line].data_buf->set_preserve_control(draw_control_chars);
 	if (p_ime_text.length() > 0) {
-		text.write[p_line].data_buf->add_string(p_ime_text, font, font_size, opentype_features, language);
+		if (p_text_changed) {
+			text.write[p_line].data_buf->add_string(p_ime_text, font, font_size, opentype_features, language);
+		}
 		if (!p_bidi_override.is_empty()) {
 			TS->shaped_text_set_bidi_override(text.write[p_line].data_buf->get_rid(), p_bidi_override);
 		}
 	} else {
-		text.write[p_line].data_buf->add_string(text[p_line].data, font, font_size, opentype_features, language);
+		if (p_text_changed) {
+			text.write[p_line].data_buf->add_string(text[p_line].data, font, font_size, opentype_features, language);
+		}
 		if (!text[p_line].bidi_override.is_empty()) {
 			TS->shaped_text_set_bidi_override(text.write[p_line].data_buf->get_rid(), text[p_line].bidi_override);
 		}
 	}
 
+	if (!p_text_changed) {
+		RID r = text.write[p_line].data_buf->get_rid();
+		int spans = TS->shaped_get_span_count(r);
+		for (int i = 0; i < spans; i++) {
+			TS->shaped_set_span_update_font(r, i, font->get_rids(), font_size, opentype_features);
+		}
+	}
+
 	// Apply tab align.
 	if (tab_size > 0) {
 		Vector<float> tabs;
@@ -266,6 +281,24 @@ void TextEdit::Text::invalidate_all_lines() {
 	}
 }
 
+void TextEdit::Text::invalidate_font() {
+	if (!is_dirty) {
+		return;
+	}
+
+	max_width = -1;
+	line_height = -1;
+
+	if (!font.is_null() && font_size > 0) {
+		font_height = font->get_height(font_size);
+	}
+
+	for (int i = 0; i < text.size(); i++) {
+		invalidate_cache(i, -1, false);
+	}
+	is_dirty = false;
+}
+
 void TextEdit::Text::invalidate_all() {
 	if (!is_dirty) {
 		return;
@@ -279,7 +312,7 @@ void TextEdit::Text::invalidate_all() {
 	}
 
 	for (int i = 0; i < text.size(); i++) {
-		invalidate_cache(i);
+		invalidate_cache(i, -1, true);
 	}
 	is_dirty = false;
 }
@@ -294,7 +327,7 @@ void TextEdit::Text::clear() {
 	line.gutters.resize(gutter_count);
 	line.data = "";
 	text.insert(0, line);
-	invalidate_cache(0);
+	invalidate_cache(0, -1, true);
 }
 
 int TextEdit::Text::get_max_width() const {
@@ -306,7 +339,7 @@ void TextEdit::Text::set(int p_line, const String &p_text, const Array &p_bidi_o
 
 	text.write[p_line].data = p_text;
 	text.write[p_line].bidi_override = p_bidi_override;
-	invalidate_cache(p_line);
+	invalidate_cache(p_line, -1, true);
 }
 
 void TextEdit::Text::insert(int p_at, const Vector<String> &p_text, const Vector<Array> &p_bidi_override) {
@@ -331,7 +364,7 @@ void TextEdit::Text::insert(int p_at, const Vector<String> &p_text, const Vector
 		line.data = p_text[i];
 		line.bidi_override = p_bidi_override[i];
 		text.write[p_at + i] = line;
-		invalidate_cache(p_at + i);
+		invalidate_cache(p_at + i, -1, true);
 	}
 }
 
@@ -1446,9 +1479,11 @@ void TextEdit::_notification(int p_what) {
 				DisplayServer::get_singleton()->window_set_ime_position(Point2(), get_viewport()->get_window_id());
 				DisplayServer::get_singleton()->window_set_ime_active(false, get_viewport()->get_window_id());
 			}
-			ime_text = "";
-			ime_selection = Point2();
-			text.invalidate_cache(caret.line, caret.column, ime_text);
+			if (!ime_text.is_empty()) {
+				ime_text = "";
+				ime_selection = Point2();
+				text.invalidate_cache(caret.line, caret.column, true, ime_text);
+			}
 
 			if (DisplayServer::get_singleton()->has_feature(DisplayServer::FEATURE_VIRTUAL_KEYBOARD) && virtual_keyboard_enabled) {
 				DisplayServer::get_singleton()->virtual_keyboard_hide();
@@ -1470,7 +1505,7 @@ void TextEdit::_notification(int p_what) {
 					t = ime_text;
 				}
 
-				text.invalidate_cache(caret.line, caret.column, t, structured_text_parser(st_parser, st_args, t));
+				text.invalidate_cache(caret.line, caret.column, true, t, structured_text_parser(st_parser, st_args, t));
 				update();
 			}
 		} break;
@@ -2538,7 +2573,7 @@ void TextEdit::_update_caches() {
 	text.set_draw_control_chars(draw_control_chars);
 	text.set_font(font);
 	text.set_font_size(font_size);
-	text.invalidate_all();
+	text.invalidate_font();
 	_update_placeholder();
 
 	/* Syntax highlighting. */
@@ -2718,7 +2753,7 @@ void TextEdit::set_text_direction(Control::TextDirection p_text_direction) {
 			dir = (TextServer::Direction)text_direction;
 		}
 		text.set_direction_and_language(dir, (!language.is_empty()) ? language : TranslationServer::get_singleton()->get_tool_locale());
-		text.invalidate_all();
+		text.invalidate_font();
 		_update_placeholder();
 
 		if (menu_dir) {
@@ -2740,7 +2775,7 @@ void TextEdit::set_opentype_feature(const String &p_name, int p_value) {
 	if (!opentype_features.has(tag) || (int)opentype_features[tag] != p_value) {
 		opentype_features[tag] = p_value;
 		text.set_font_features(opentype_features);
-		text.invalidate_all();
+		text.invalidate_font();
 		_update_placeholder();
 		update();
 	}
@@ -2757,7 +2792,7 @@ int TextEdit::get_opentype_feature(const String &p_name) const {
 void TextEdit::clear_opentype_features() {
 	opentype_features.clear();
 	text.set_font_features(opentype_features);
-	text.invalidate_all();
+	text.invalidate_font();
 	_update_placeholder();
 	update();
 }
@@ -4852,7 +4887,7 @@ void TextEdit::set_draw_control_chars(bool p_enabled) {
 			menu->set_item_checked(menu->get_item_index(MENU_DISPLAY_UCC), draw_control_chars);
 		}
 		text.set_draw_control_chars(draw_control_chars);
-		text.invalidate_all();
+		text.invalidate_font();
 		_update_placeholder();
 		update();
 	}
@@ -5319,7 +5354,7 @@ bool TextEdit::_set(const StringName &p_name, const Variant &p_value) {
 			if (opentype_features.has(tag)) {
 				opentype_features.erase(tag);
 				text.set_font_features(opentype_features);
-				text.invalidate_all();
+				text.invalidate_font();
 				_update_placeholder();
 				update();
 			}
@@ -5327,7 +5362,7 @@ bool TextEdit::_set(const StringName &p_name, const Variant &p_value) {
 			if (!opentype_features.has(tag) || (int)opentype_features[tag] != value) {
 				opentype_features[tag] = value;
 				text.set_font_features(opentype_features);
-				text.invalidate_all();
+				text.invalidate_font();
 				_update_placeholder();
 				update();
 			}
diff --git a/scene/gui/text_edit.h b/scene/gui/text_edit.h
index 079890249e..83a63ae40a 100644
--- a/scene/gui/text_edit.h
+++ b/scene/gui/text_edit.h
@@ -210,7 +210,8 @@ private:
 		int size() const { return text.size(); }
 		void clear();
 
-		void invalidate_cache(int p_line, int p_column = -1, const String &p_ime_text = String(), const Array &p_bidi_override = Array());
+		void invalidate_cache(int p_line, int p_column = -1, bool p_text_changed = false, const String &p_ime_text = String(), const Array &p_bidi_override = Array());
+		void invalidate_font();
 		void invalidate_all();
 		void invalidate_all_lines();