third_party/blink/renderer/core/style/shadow_list.h

/*
 * Copyright (C) 2013 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions are
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_STYLE_SHADOW_LIST_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_STYLE_SHADOW_LIST_H_

#include <memory>
#include "third_party/blink/renderer/core/style/shadow_data.h"
#include "third_party/blink/renderer/platform/geometry/float_rect_outsets.h"
#include "third_party/blink/renderer/platform/graphics/draw_looper_builder.h"
#include "third_party/blink/renderer/platform/wtf/ref_counted.h"
#include "third_party/blink/renderer/platform/wtf/vector.h"

namespace blink {

class FloatRect;

typedef Vector<ShadowData, 1> ShadowDataVector;

// These are used to store shadows in specified order, but we usually want to
// iterate over them backwards as the first-specified shadow is painted on top.
class ShadowList : public RefCounted<ShadowList> {
 public:
  // This consumes passed in vector.
  static scoped_refptr<ShadowList> Adopt(ShadowDataVector& shadows) {
    return base::AdoptRef(new ShadowList(shadows));
  }
  const ShadowDataVector& Shadows() const { return shadows_; }
  bool operator==(const ShadowList& o) const { return shadows_ == o.shadows_; }
  bool operator!=(const ShadowList& o) const { return !(*this == o); }

  // Outsets needed to include all shadows in this list, as well as the
  // source (i.e. no outsets will be negative).
  FloatRectOutsets RectOutsetsIncludingOriginal() const;

  void AdjustRectForShadow(FloatRect&) const;

  sk_sp<SkDrawLooper> CreateDrawLooper(DrawLooperBuilder::ShadowAlphaMode,
                                       const Color& current_color,
                                       bool is_horizontal = true) const;

 private:
  ShadowList(ShadowDataVector& shadows) {
    // If we have no shadows, we use a null ShadowList
    DCHECK(!shadows.IsEmpty());
    shadows_.swap(shadows);
    shadows_.ShrinkToFit();
  }
  ShadowDataVector shadows_;
};

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_STYLE_SHADOW_LIST_H_