third_party/WebKit/Source/core/style/ShadowList.cpp

/*
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 * modification, are permitted provided that the following conditions are
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 * in the documentation and/or other materials provided with the
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 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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#include "core/style/ShadowList.h"

#include "platform/geometry/FloatRect.h"
#include <memory>

namespace blink {

FloatRectOutsets ShadowList::RectOutsetsIncludingOriginal() const {
  FloatRectOutsets outsets;
  for (const ShadowData& shadow : Shadows()) {
    if (shadow.Style() == kInset)
      continue;
    outsets.Unite(shadow.RectOutsets());
  }
  return outsets;
}

void ShadowList::AdjustRectForShadow(FloatRect& rect) const {
  rect.Expand(RectOutsetsIncludingOriginal());
}

sk_sp<SkDrawLooper> ShadowList::CreateDrawLooper(
    DrawLooperBuilder::ShadowAlphaMode alpha_mode,
    const Color& current_color,
    bool is_horizontal) const {
  DrawLooperBuilder draw_looper_builder;
  for (size_t i = Shadows().size(); i--;) {
    const ShadowData& shadow = Shadows()[i];
    float shadow_x = is_horizontal ? shadow.X() : shadow.Y();
    float shadow_y = is_horizontal ? shadow.Y() : -shadow.X();
    draw_looper_builder.AddShadow(FloatSize(shadow_x, shadow_y), shadow.Blur(),
                                  shadow.GetColor().Resolve(current_color),
                                  DrawLooperBuilder::kShadowRespectsTransforms,
                                  alpha_mode);
  }
  draw_looper_builder.AddUnmodifiedContent();
  return draw_looper_builder.DetachDrawLooper();
}

}  // namespace blink