| /* |
| * Copyright 2019 Google Inc. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef LIB_TXT_SRC_PARAGRAPH_BUILDER_SKIA_H_ |
| #define LIB_TXT_SRC_PARAGRAPH_BUILDER_SKIA_H_ |
| |
| #include "txt/paragraph_builder.h" |
| |
| #include "flutter/display_list/dl_paint.h" |
| #include "third_party/skia/modules/skparagraph/include/ParagraphBuilder.h" |
| |
| namespace txt { |
| |
| //------------------------------------------------------------------------------ |
| /// @brief ParagraphBuilder implementation using Skia's text layout module. |
| /// |
| /// @note Despite the suffix "Skia", this class is not specific to Skia |
| /// and is also used with the Impeller backend. |
| class ParagraphBuilderSkia : public ParagraphBuilder { |
| public: |
| ParagraphBuilderSkia(const ParagraphStyle& style, |
| std::shared_ptr<FontCollection> font_collection, |
| const bool impeller_enabled); |
| |
| virtual ~ParagraphBuilderSkia(); |
| |
| virtual void PushStyle(const TextStyle& style) override; |
| virtual void Pop() override; |
| virtual const TextStyle& PeekStyle() override; |
| virtual void AddText(const std::u16string& text) override; |
| virtual void AddPlaceholder(PlaceholderRun& span) override; |
| virtual std::unique_ptr<Paragraph> Build() override; |
| |
| private: |
| skia::textlayout::ParagraphPainter::PaintID CreatePaintID( |
| const flutter::DlPaint& dl_paint); |
| skia::textlayout::ParagraphStyle TxtToSkia(const ParagraphStyle& txt); |
| skia::textlayout::TextStyle TxtToSkia(const TextStyle& txt); |
| |
| std::shared_ptr<skia::textlayout::ParagraphBuilder> builder_; |
| TextStyle base_style_; |
| |
| /// @brief Whether Impeller is enabled in the runtime. |
| /// |
| /// @note As of the time of this writing, this is used to draw text |
| /// decorations (i.e. dashed and dotted lines) directly using the |
| /// `drawLine` API, because Impeller's path rendering does not |
| /// support dashed and dotted lines (but Skia's does). |
| const bool impeller_enabled_; |
| std::stack<TextStyle> txt_style_stack_; |
| std::vector<flutter::DlPaint> dl_paints_; |
| }; |
| |
| } // namespace txt |
| |
| #endif // LIB_TXT_SRC_PARAGRAPH_BUILDER_SKIA_H_ |