SVG export module, converting drawing commands to SVG text

include/tgfx/core/Canvas.h

@@ -335,5 +335,6 @@ class Canvas {
   friend class Surface;
   friend class Picture;
   friend class Recorder;
+  friend class SVGGenerator;
 };
 }  // namespace tgfx

include/tgfx/core/ImageFilter.h

@@ -169,5 +169,6 @@ class ImageFilter {
   friend class InnerShadowImageFilter;
   friend class ComposeImageFilter;
   friend class FilterImage;
+  friend class ImageFilterCaster;
 };
 }  // namespace tgfx

include/tgfx/core/Picture.h

@@ -25,6 +25,7 @@ namespace tgfx {
 class Record;
 class Canvas;
 class DrawContext;
+class SVGContext;
 class MCState;
 class Image;
 
@@ -61,6 +62,7 @@ class Picture {
   friend class MeasureContext;
   friend class RenderContext;
   friend class RecordingContext;
+  friend class SVGContext;
   friend class Image;
   friend class PictureImage;
   friend class Canvas;

include/tgfx/core/Shader.h

@@ -151,5 +151,6 @@ class Shader {
 
   friend class FragmentProcessor;
   friend class Canvas;
+  friend class ShaderCaster;
 };
 }  // namespace tgfx

include/tgfx/svg/SVGGenerator.h

@@ -0,0 +1,65 @@
+/////////////////////////////////////////////////////////////////////////////////////////////////
+//
+//  Tencent is pleased to support the open source community by making tgfx available.
+//
+//  Copyright (C) 2024 THL A29 Limited, a Tencent company. All rights reserved.
+//
+//  Licensed under the BSD 3-Clause License (the "License"); you may not use this file except
+//  in compliance with the License. You may obtain a copy of the License at
+//
+//      https://opensource.org/licenses/BSD-3-Clause
+//
+//  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.
+//
+/////////////////////////////////////////////////////////////////////////////////////////////////
+
+#pragma once
+
+#include <sstream>
+#include "tgfx/core/Canvas.h"
+#include "tgfx/gpu/Context.h"
+
+namespace tgfx {
+class SVGContext;
+
+/**
+ * SVGGenerator is a class used to generate SVG text, converting drawing commands in the Canvas to
+ * SVG text.
+ */
+class SVGGenerator {
+ public:
+  SVGGenerator() = default;
+  ~SVGGenerator();
+
+  /**
+   * Begin generating SVG text and return a Canvas object for drawing SVG graphics.
+   *
+   * @param GPUContext used to convert some rendering commands into image data.
+   * @param size The size sets the size of the SVG, and content that exceeds the display area in the
+   * SVG will be clipped.
+   * @param isPretty Whether to format the generated SVG text with "/n"、"/t"".
+   * @return Canvas* 
+   */
+  Canvas* beginGenerate(Context* GPUContext, const ISize& size, bool isPretty = true);
+
+  /**
+   * Returns the recording canvas if it is active, or nullptr.
+   */
+  Canvas* getCanvas() const;
+
+  /**
+   * Finish generating SVG text and return the generated SVG text. If no recording is active.
+   */
+  std::string finishGenerate();
+
+ private:
+  bool _actively = false;
+  SVGContext* _context = nullptr;
+  Canvas* _canvas = nullptr;
+  std::stringstream _svgStream;
+};
+
+}  // namespace tgfx

src/svg/Caster.cpp

@@ -0,0 +1,69 @@
+/////////////////////////////////////////////////////////////////////////////////////////////////
+//
+//  Tencent is pleased to support the open source community by making tgfx available.
+//
+//  Copyright (C) 2024 THL A29 Limited, a Tencent company. All rights reserved.
+//
+//  Licensed under the BSD 3-Clause License (the "License"); you may not use this file except
+//  in compliance with the License. You may obtain a copy of the License at
+//
+//      https://opensource.org/licenses/BSD-3-Clause
+//
+//  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.
+//
+/////////////////////////////////////////////////////////////////////////////////////////////////
+
+#include "Caster.h"
+
+namespace tgfx {
+std::shared_ptr<const ColorShader> ShaderCaster::CastToColorShader(
+    const std::shared_ptr<Shader>& shader) {
+  if (shader->type() == Shader::Type::Color) {
+    return std::static_pointer_cast<const ColorShader>(shader);
+  }
+  return nullptr;
+}
+
+std::shared_ptr<const ImageShader> ShaderCaster::CastToImageShader(
+    const std::shared_ptr<Shader>& shader) {
+  if (shader->type() == Shader::Type::Image) {
+    return std::static_pointer_cast<const ImageShader>(shader);
+  }
+  return nullptr;
+}
+
+std::shared_ptr<const GradientShader> ShaderCaster::CastToGradientShader(
+    const std::shared_ptr<Shader>& shader) {
+  if (shader->type() == Shader::Type::Gradient) {
+    return std::static_pointer_cast<const GradientShader>(shader);
+  }
+  return nullptr;
+}
+
+std::shared_ptr<const BlurImageFilter> ImageFilterCaster::CastToBlurImageFilter(
+    const std::shared_ptr<ImageFilter>& imageFilter) {
+  if (imageFilter->type() == ImageFilter::Type::Blur) {
+    return std::static_pointer_cast<const BlurImageFilter>(imageFilter);
+  }
+  return nullptr;
+}
+std::shared_ptr<const DropShadowImageFilter> ImageFilterCaster::CastToDropShadowImageFilter(
+    const std::shared_ptr<ImageFilter>& imageFilter) {
+  if (imageFilter->type() == ImageFilter::Type::DropShadow) {
+    return std::static_pointer_cast<const DropShadowImageFilter>(imageFilter);
+  }
+  return nullptr;
+}
+
+std::shared_ptr<const InnerShadowImageFilter> ImageFilterCaster::CastToInnerShadowImageFilter(
+    const std::shared_ptr<ImageFilter>& imageFilter) {
+  if (imageFilter->type() == ImageFilter::Type::InnerShadow) {
+    return std::static_pointer_cast<const InnerShadowImageFilter>(imageFilter);
+  }
+  return nullptr;
+}
+
+}  // namespace tgfx

src/svg/Caster.h

@@ -0,0 +1,55 @@
+/////////////////////////////////////////////////////////////////////////////////////////////////
+//
+//  Tencent is pleased to support the open source community by making tgfx available.
+//
+//  Copyright (C) 2024 THL A29 Limited, a Tencent company. All rights reserved.
+//
+//  Licensed under the BSD 3-Clause License (the "License"); you may not use this file except
+//  in compliance with the License. You may obtain a copy of the License at
+//
+//      https://opensource.org/licenses/BSD-3-Clause
+//
+//  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.
+//
+/////////////////////////////////////////////////////////////////////////////////////////////////
+
+#include <memory>
+#include "core/filters/BlurImageFilter.h"
+#include "core/filters/DropShadowImageFilter.h"
+#include "core/filters/InnerShadowImageFilter.h"
+#include "core/shaders/ColorShader.h"
+#include "core/shaders/GradientShader.h"
+#include "core/shaders/ImageShader.h"
+
+#pragma once
+
+namespace tgfx {
+
+class ShaderCaster {
+ public:
+  static std::shared_ptr<const ColorShader> CastToColorShader(
+      const std::shared_ptr<Shader>& shader);
+
+  static std::shared_ptr<const ImageShader> CastToImageShader(
+      const std::shared_ptr<Shader>& shader);
+
+  static std::shared_ptr<const GradientShader> CastToGradientShader(
+      const std::shared_ptr<Shader>& shader);
+};
+
+class ImageFilterCaster {
+ public:
+  static std::shared_ptr<const BlurImageFilter> CastToBlurImageFilter(
+      const std::shared_ptr<ImageFilter>& imageFilter);
+
+  static std::shared_ptr<const DropShadowImageFilter> CastToDropShadowImageFilter(
+      const std::shared_ptr<ImageFilter>& imageFilter);
+
+  static std::shared_ptr<const InnerShadowImageFilter> CastToInnerShadowImageFilter(
+      const std::shared_ptr<ImageFilter>& imageFilter);
+};
+
+}  // namespace tgfx