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/effects/SkColorMatrix.h"
11 #include "modules/skottie/src/SkottieValue.h"
12 #include "modules/sksg/include/SkSGColorFilter.h"
13 #include "src/utils/SkJSON.h"
14
15 namespace skottie {
16 namespace internal {
17
18 namespace {
19
20 class InvertEffectAdapter final : public AnimatablePropertyContainer {
21 public:
Make(const skjson::ArrayValue & jprops,sk_sp<sksg::RenderNode> layer,const AnimationBuilder * abuilder)22 static sk_sp<InvertEffectAdapter> Make(const skjson::ArrayValue& jprops,
23 sk_sp<sksg::RenderNode> layer,
24 const AnimationBuilder* abuilder) {
25 return sk_sp<InvertEffectAdapter>(
26 new InvertEffectAdapter(jprops, std::move(layer), abuilder));
27 }
28
node() const29 const sk_sp<sksg::ExternalColorFilter>& node() const { return fColorFilter; }
30
31 private:
InvertEffectAdapter(const skjson::ArrayValue & jprops,sk_sp<sksg::RenderNode> layer,const AnimationBuilder * abuilder)32 InvertEffectAdapter(const skjson::ArrayValue& jprops,
33 sk_sp<sksg::RenderNode> layer,
34 const AnimationBuilder* abuilder)
35 : fColorFilter(sksg::ExternalColorFilter::Make(std::move(layer))) {
36 enum : size_t {
37 kChannel_Index = 0,
38 };
39
40 EffectBinder(jprops, *abuilder, this).bind(kChannel_Index, fChannel);
41 }
42
onSync()43 void onSync() override {
44 enum class CS { kRGB, kHSL, kYIQ };
45
46 struct STColorMatrix {
47 std::array<float,4> scale,
48 trans;
49 CS cs;
50 };
51
52 const auto stcm = [this]() -> STColorMatrix {
53 // https://helpx.adobe.com/after-effects/using/channel-effects.html#invert_effect
54 enum : uint8_t {
55 kRGB_Channel = 1,
56 kR_Channel = 2,
57 kG_Channel = 3,
58 kB_Channel = 4,
59
60 // NB: HLS vs. HSL
61 kHLS_Channel = 6,
62 kH_Channel = 7,
63 kL_Channel = 8,
64 kS_Channel = 9,
65
66 kYIQ_Channel = 11,
67 kY_Channel = 12,
68 kI_Channel = 13,
69 kQ_Channel = 14,
70
71 kA_Channel = 16,
72 };
73
74 switch (static_cast<uint8_t>(fChannel)) {
75 case kR_Channel: return { {-1, 1, 1, 1}, { 1,0,0,0}, CS::kRGB }; // r' = 1 - r
76 case kG_Channel: return { { 1,-1, 1, 1}, { 0,1,0,0}, CS::kRGB }; // g' = 1 - g
77 case kB_Channel: return { { 1, 1,-1, 1}, { 0,0,1,0}, CS::kRGB }; // b' = 1 - b
78 case kA_Channel: return { { 1, 1, 1,-1}, { 0,0,0,1}, CS::kRGB }; // a' = 1 - a
79 case kRGB_Channel: return { {-1,-1,-1, 1}, { 1,1,1,0}, CS::kRGB };
80
81 case kH_Channel: return { {-1, 1, 1, 1}, {.5f,0,0,0}, CS::kHSL }; // h' = .5 - h
82 case kS_Channel: return { { 1,-1, 1, 1}, { 0,1,0,0}, CS::kHSL }; // s' = 1 - s
83 case kL_Channel: return { { 1, 1,-1, 1}, { 0,0,1,0}, CS::kHSL }; // l' = 1 - l
84 case kHLS_Channel: return { {-1,-1,-1, 1}, {.5f,1,1,0}, CS::kHSL };
85
86 case kY_Channel: return { {-1, 1, 1, 1}, { 1,0,0,0}, CS::kYIQ }; // y' = 1 - y
87 case kI_Channel: return { { 1,-1, 1, 1}, { 0,0,0,0}, CS::kYIQ }; // i' = -i
88 case kQ_Channel: return { { 1, 1,-1, 1}, { 0,0,0,0}, CS::kYIQ }; // q' = -q
89 case kYIQ_Channel: return { {-1,-1,-1, 1}, { 1,0,0,0}, CS::kYIQ };
90
91 default: return { { 1, 1, 1, 1}, { 0,0,0,0}, CS::kRGB };
92 }
93
94 SkUNREACHABLE;
95 }();
96
97 SkColorMatrix m(
98 stcm.scale[0], 0, 0, 0, stcm.trans[0],
99 0, stcm.scale[1], 0, 0, stcm.trans[1],
100 0, 0, stcm.scale[2], 0, stcm.trans[2],
101 0, 0, 0, stcm.scale[3], stcm.trans[3]
102
103 );
104
105 if (stcm.cs == CS::kYIQ) {
106 // https://en.wikipedia.org/wiki/YIQ
107 static constexpr SkColorMatrix RGB2YIQ(
108 0.2990f, 0.5870f, 0.1140f, 0, 0,
109 0.5959f, -0.2746f, -0.3213f, 0, 0,
110 0.2115f, -0.5227f, 0.3112f, 0, 0,
111 0, 0, 0, 1, 0
112 );
113 static constexpr SkColorMatrix YIQ2RGB(
114 1, 0.9560f, 0.6190f, 0, 0,
115 1, -0.2720f, -0.6470f, 0, 0,
116 1, -1.1060f, 1.7030f, 0, 0,
117 0, 0, 0, 1, 0
118 );
119
120 m.preConcat (RGB2YIQ);
121 m.postConcat(YIQ2RGB);
122 }
123
124 fColorFilter->setColorFilter(stcm.cs == CS::kHSL ? SkColorFilters::HSLAMatrix(m)
125 : SkColorFilters::Matrix(m));
126 }
127
128 const sk_sp<sksg::ExternalColorFilter> fColorFilter;
129
130 float fChannel = 0;
131 };
132
133 } // namespace
134
attachInvertEffect(const skjson::ArrayValue & jprops,sk_sp<sksg::RenderNode> layer) const135 sk_sp<sksg::RenderNode> EffectBuilder::attachInvertEffect(const skjson::ArrayValue& jprops,
136 sk_sp<sksg::RenderNode> layer) const {
137 return fBuilder->attachDiscardableAdapter<InvertEffectAdapter>(jprops,
138 std::move(layer),
139 fBuilder);
140 }
141
142 } // namespace internal
143 } // namespace skottie
144