1 /*
2  * Copyright 2019 Google Inc.
3  *
4  * Use of this source code is governed by a BSD-style license that can be
5  * found in the LICENSE file.
6  */
7 
8 #include "modules/skottie/src/effects/Effects.h"
9 
10 #include "include/private/SkTPin.h"
11 #include "modules/skottie/src/SkottieValue.h"
12 #include "modules/sksg/include/SkSGRenderEffect.h"
13 #include "src/utils/SkJSON.h"
14 
15 namespace skottie {
16 namespace internal {
17 
18 namespace  {
19 
20 class DropShadowAdapter final : public AnimatablePropertyContainer {
21 public:
Make(const skjson::ArrayValue & jprops,sk_sp<sksg::RenderNode> layer,const AnimationBuilder & abuilder)22     static sk_sp<DropShadowAdapter> Make(const skjson::ArrayValue& jprops,
23                                          sk_sp<sksg::RenderNode> layer,
24                                          const AnimationBuilder& abuilder) {
25         enum : size_t {
26             kShadowColor_Index = 0,
27                 kOpacity_Index = 1,
28               kDirection_Index = 2,
29                kDistance_Index = 3,
30                kSoftness_Index = 4,
31              kShadowOnly_Index = 5,
32         };
33 
34         sk_sp<DropShadowAdapter> adapter(new DropShadowAdapter(std::move(layer)));
35 
36         EffectBinder(jprops, abuilder, adapter.get())
37                 .bind(kShadowColor_Index, adapter->fColor    )
38                 .bind(    kOpacity_Index, adapter->fOpacity  )
39                 .bind(  kDirection_Index, adapter->fDirection)
40                 .bind(   kDistance_Index, adapter->fDistance )
41                 .bind(   kSoftness_Index, adapter->fSoftness )
42                 .bind( kShadowOnly_Index, adapter->fShdwOnly );
43 
44         return adapter;
45     }
46 
node() const47     const sk_sp<sksg::RenderNode>& node() const { return fImageFilterEffect; }
48 
49 private:
DropShadowAdapter(sk_sp<sksg::RenderNode> layer)50     explicit DropShadowAdapter(sk_sp<sksg::RenderNode> layer)
51         : fDropShadow(sksg::DropShadowImageFilter::Make())
52         , fImageFilterEffect(sksg::ImageFilterEffect::Make(std::move(layer), fDropShadow)) {}
53 
onSync()54     void onSync() override {
55         // fColor -> RGB, fOpacity -> A
56         const SkColor color = fColor;
57         fDropShadow->setColor(SkColorSetA(color, SkTPin(SkScalarRoundToInt(fOpacity), 0, 255)));
58 
59         // The offset is specified in terms of a bearing + distance.
60         const auto rad = SkDegreesToRadians(90 - fDirection);
61         fDropShadow->setOffset(SkVector::Make( fDistance * SkScalarCos(rad),
62                                               -fDistance * SkScalarSin(rad)));
63 
64         const auto sigma = fSoftness * kBlurSizeToSigma;
65         fDropShadow->setSigma(SkVector::Make(sigma, sigma));
66 
67         fDropShadow->setMode(SkToBool(fShdwOnly)
68                                 ? sksg::DropShadowImageFilter::Mode::kShadowOnly
69                                 : sksg::DropShadowImageFilter::Mode::kShadowAndForeground);
70     }
71 
72     const sk_sp<sksg::DropShadowImageFilter> fDropShadow;
73     const sk_sp<sksg::RenderNode>            fImageFilterEffect;
74 
75     VectorValue fColor     = { 0, 0, 0, 1 };
76     ScalarValue fOpacity   = 255,
77                 fDirection = 0,
78                 fDistance  = 0,
79                 fSoftness  = 0,
80                 fShdwOnly  = 0;
81 };
82 
83 }  // namespace
84 
attachDropShadowEffect(const skjson::ArrayValue & jprops,sk_sp<sksg::RenderNode> layer) const85 sk_sp<sksg::RenderNode> EffectBuilder::attachDropShadowEffect(const skjson::ArrayValue& jprops,
86                                                               sk_sp<sksg::RenderNode> layer) const {
87     return fBuilder->attachDiscardableAdapter<DropShadowAdapter>(jprops,
88                                                                  std::move(layer),
89                                                                  *fBuilder);
90 }
91 
92 } // namespace internal
93 } // namespace skottie
94