xref: /aosp_15_r20/external/skia/modules/skottie/src/Composition.cpp (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
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/Composition.h"
9 
10 #include "include/core/SkString.h"
11 #include "include/private/base/SkTPin.h"
12 #include "include/private/base/SkTo.h"
13 #include "modules/skottie/include/Skottie.h"
14 #include "modules/skottie/src/Camera.h"
15 #include "modules/skottie/src/SkottieJson.h"
16 #include "modules/skottie/src/SkottiePriv.h"
17 #include "modules/sksg/include/SkSGGroup.h"
18 #include "modules/sksg/include/SkSGRenderNode.h"
19 #include "modules/sksg/include/SkSGTransform.h"
20 #include "src/utils/SkJSON.h"
21 
22 #include <algorithm>
23 #include <utility>
24 
25 namespace skottie {
26 namespace internal {
27 
ScopedAssetRef(const AnimationBuilder * abuilder,const skjson::ObjectValue & jlayer)28 AnimationBuilder::ScopedAssetRef::ScopedAssetRef(const AnimationBuilder* abuilder,
29                                                  const skjson::ObjectValue& jlayer) {
30     const auto refId = ParseDefault<SkString>(jlayer["refId"], SkString());
31     if (refId.isEmpty()) {
32         abuilder->log(Logger::Level::kError, nullptr, "Layer missing refId.");
33         return;
34     }
35 
36     const auto* asset_info = abuilder->fAssets.find(refId);
37     if (!asset_info) {
38         abuilder->log(Logger::Level::kError, nullptr, "Asset not found: '%s'.", refId.c_str());
39         return;
40     }
41 
42     if (asset_info->fIsAttaching) {
43         abuilder->log(Logger::Level::kError, nullptr,
44                   "Asset cycle detected for: '%s'", refId.c_str());
45         return;
46     }
47 
48     asset_info->fIsAttaching = true;
49 
50     fInfo = asset_info;
51 }
52 
CompositionBuilder(const AnimationBuilder & abuilder,const SkSize & size,const skjson::ObjectValue & jcomp)53 CompositionBuilder::CompositionBuilder(const AnimationBuilder& abuilder,
54                                        const SkSize& size,
55                                        const skjson::ObjectValue& jcomp)
56     : fSize(size) {
57 
58     // Optional motion blur params.
59     if (const skjson::ObjectValue* jmb = jcomp["mb"]) {
60         static constexpr size_t kMaxSamplesPerFrame = 64;
61         fMotionBlurSamples = std::min(ParseDefault<size_t>((*jmb)["spf"], 1ul),
62                                       kMaxSamplesPerFrame);
63         fMotionBlurAngle = SkTPin(ParseDefault((*jmb)["sa"], 0.0f),    0.0f, 720.0f);
64         fMotionBlurPhase = SkTPin(ParseDefault((*jmb)["sp"], 0.0f), -360.0f, 360.0f);
65     }
66 
67     int camera_builder_index = -1;
68 
69     // Prepare layer builders.
70     if (const skjson::ArrayValue* jlayers = jcomp["layers"]) {
71         fLayerBuilders.reserve(SkToInt(jlayers->size()));
72         for (const skjson::ObjectValue* jlayer : *jlayers) {
73             if (!jlayer) continue;
74 
75             const auto  lbuilder_index = fLayerBuilders.size();
76             fLayerBuilders.emplace_back(*jlayer, fSize);
77             const auto& lbuilder = fLayerBuilders.back();
78 
79             fLayerIndexMap.set(lbuilder.index(), lbuilder_index);
80 
81             // Keep track of the camera builder.
82             if (lbuilder.isCamera()) {
83                 // We only support one (first) camera for now.
84                 if (camera_builder_index < 0) {
85                     camera_builder_index = SkToInt(lbuilder_index);
86                 } else {
87                     abuilder.log(Logger::Level::kWarning, jlayer,
88                                  "Ignoring duplicate camera layer.");
89                 }
90             }
91         }
92     }
93 
94     // Attach a camera transform upfront, if needed (required to build
95     // all other 3D transform chains).
96     if (camera_builder_index >= 0) {
97         // Explicit camera.
98         fCameraTransform = fLayerBuilders[camera_builder_index].buildTransform(abuilder, this);
99     } else if (ParseDefault<int>(jcomp["ddd"], 0) && !fSize.isEmpty()) {
100         // Default/implicit camera when 3D layers are present.
101         fCameraTransform = CameraAdaper::DefaultCameraTransform(fSize);
102     }
103 }
104 
105 CompositionBuilder::~CompositionBuilder() = default;
106 
layerBuilder(int layer_index)107 LayerBuilder* CompositionBuilder::layerBuilder(int layer_index) {
108     if (layer_index < 0) {
109         return nullptr;
110     }
111 
112     if (const auto* idx = fLayerIndexMap.find(layer_index)) {
113         return &fLayerBuilders[SkToInt(*idx)];
114     }
115 
116     return nullptr;
117 }
118 
build(const AnimationBuilder & abuilder)119 sk_sp<sksg::RenderNode> CompositionBuilder::build(const AnimationBuilder& abuilder) {
120     // First pass - transitively attach layer transform chains.
121     for (auto& lbuilder : fLayerBuilders) {
122         lbuilder.buildTransform(abuilder, this);
123     }
124 
125     // Second pass - attach actual layer contents and finalize the layer render tree.
126     std::vector<sk_sp<sksg::RenderNode>> layers;
127     layers.reserve(fLayerBuilders.size());
128 
129     LayerBuilder* prev_layer = nullptr;
130     for (auto& lbuilder : fLayerBuilders) {
131         if (auto layer = lbuilder.buildRenderTree(abuilder, this, prev_layer)) {
132             layers.push_back(std::move(layer));
133         }
134         prev_layer = &lbuilder;
135     }
136 
137     if (layers.empty()) {
138         return nullptr;
139     }
140 
141     if (layers.size() == 1) {
142         return std::move(layers[0]);
143     }
144 
145     // Layers are painted in bottom->top order.
146     std::reverse(layers.begin(), layers.end());
147     layers.shrink_to_fit();
148 
149     return sksg::Group::Make(std::move(layers));
150 }
151 
152 } // namespace internal
153 } // namespace skottie
154