third_party/WebKit/Source/platform/graphics/GraphicsContextState.h

// Copyright (C) 2013 Google Inc. All rights reserved.
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#ifndef GraphicsContextState_h
#define GraphicsContextState_h

#include <memory>
#include "platform/graphics/DrawLooperBuilder.h"
#include "platform/graphics/GraphicsTypes.h"
#include "platform/graphics/StrokeData.h"
#include "platform/graphics/paint/PaintFlags.h"
#include "platform/wtf/Allocator.h"
#include "platform/wtf/Noncopyable.h"
#include "platform/wtf/PtrUtil.h"
#include "third_party/skia/include/core/SkColorFilter.h"
#include "third_party/skia/include/core/SkRefCnt.h"

namespace blink {

// Encapsulates the state information we store for each pushed graphics state.
// Only GraphicsContext can use this class.
class PLATFORM_EXPORT GraphicsContextState final {
  USING_FAST_MALLOC(GraphicsContextState);

 public:
  static std::unique_ptr<GraphicsContextState> Create() {
    return WTF::WrapUnique(new GraphicsContextState());
  }

  static std::unique_ptr<GraphicsContextState> CreateAndCopy(
      const GraphicsContextState& other) {
    return WTF::WrapUnique(new GraphicsContextState(other));
  }

  void Copy(const GraphicsContextState&);

  // PaintFlags objects that reflect the current state. If the length of the
  // path to be stroked is known, pass it in for correct dash or dot placement.
  const PaintFlags& StrokeFlags(int stroked_path_length = 0) const;
  const PaintFlags& FillFlags() const { return fill_flags_; }

  uint16_t SaveCount() const { return save_count_; }
  void IncrementSaveCount() { ++save_count_; }
  void DecrementSaveCount() { --save_count_; }

  // Stroke data
  Color StrokeColor() const { return stroke_flags_.getColor(); }
  void SetStrokeColor(const Color&);

  const StrokeData& GetStrokeData() const { return stroke_data_; }
  void SetStrokeStyle(StrokeStyle);
  void SetStrokeThickness(float);
  void SetLineCap(LineCap);
  void SetLineJoin(LineJoin);
  void SetMiterLimit(float);
  void SetLineDash(const DashArray&, float);

  // Fill data
  Color FillColor() const { return fill_flags_.getColor(); }
  void SetFillColor(const Color&);

  // Shadow. (This will need tweaking if we use draw loopers for other things.)
  SkDrawLooper* DrawLooper() const {
    DCHECK_EQ(fill_flags_.getLooper(), stroke_flags_.getLooper());
    return fill_flags_.getLooper().get();
  }
  void SetDrawLooper(sk_sp<SkDrawLooper>);

  // Text. (See TextModeFill & friends.)
  TextDrawingModeFlags TextDrawingMode() const { return text_drawing_mode_; }
  void SetTextDrawingMode(TextDrawingModeFlags mode) {
    text_drawing_mode_ = mode;
  }

  SkColorFilter* GetColorFilter() const {
    DCHECK_EQ(fill_flags_.getColorFilter(), stroke_flags_.getColorFilter());
    return fill_flags_.getColorFilter().get();
  }
  void SetColorFilter(sk_sp<SkColorFilter>);

  // Image interpolation control.
  InterpolationQuality GetInterpolationQuality() const {
    return interpolation_quality_;
  }
  void SetInterpolationQuality(InterpolationQuality);

  bool ShouldAntialias() const { return should_antialias_; }
  void SetShouldAntialias(bool);

 private:
  GraphicsContextState();
  explicit GraphicsContextState(const GraphicsContextState&);
  GraphicsContextState& operator=(const GraphicsContextState&);

  // This is mutable to enable dash path effect updates when the paint is
  // fetched for use.
  mutable PaintFlags stroke_flags_;
  PaintFlags fill_flags_;

  StrokeData stroke_data_;

  TextDrawingModeFlags text_drawing_mode_;

  InterpolationQuality interpolation_quality_;

  uint16_t save_count_;

  bool should_antialias_ : 1;
};

}  // namespace blink

#endif  // GraphicsContextState_h