| /* |
| * Copyright 2021 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "modules/skottie/src/effects/Effects.h" |
| |
| #include "include/effects/SkRuntimeEffect.h" |
| #include "include/utils/SkRandom.h" |
| #include "modules/skottie/src/Adapter.h" |
| #include "modules/skottie/src/SkottieJson.h" |
| #include "modules/skottie/src/SkottieValue.h" |
| #include "modules/sksg/include/SkSGRenderNode.h" |
| |
| namespace skottie::internal { |
| namespace { |
| |
| // An implementation of the ADBE Fractal Noise effect: |
| // |
| // - multiple noise sublayers (octaves) are combined using a weighted average |
| // - each layer is subject to a (cumulative) transform, filter and post-sampling options |
| // |
| // Parameters: |
| // |
| // * Noise Type -- controls noise layer post-sampling filtering |
| // (Block, Linear, Soft Linear, Spline) |
| // * Fractal Type -- determines a noise layer post-filtering transformation |
| // (Basic, Turbulent Smooth, Turbulent Basic, etc) |
| // * Transform -- offset/scale/rotate the noise effect (local matrix) |
| // |
| // * Complexity -- number of sublayers; |
| // can be fractional, where the fractional part modulates the last layer |
| // * Evolution -- controls noise topology in a gradual manner (can be animated for smooth |
| // noise transitions) |
| // * Sub Influence -- relative amplitude weight for sublayers (cumulative) |
| // |
| // * Sub Scaling/Rotation/Offset -- relative scale for sublayers (cumulative) |
| // |
| // * Invert -- invert noise values |
| // |
| // * Contrast -- apply a contrast to the noise result |
| // |
| // * Brightness -- apply a brightness effect to the noise result |
| // |
| // |
| // TODO: |
| // - Invert |
| // - Contrast/Brightness |
| |
| static constexpr char gNoiseEffectSkSL[] = |
| "uniform half3x3 u_submatrix;" // sublayer transform |
| |
| "uniform half u_octaves," // number of octaves (can be fractional) |
| "u_persistence," // relative octave weight |
| "u_evolution;" // evolution/seed |
| |
| // Hash based on hash13 (https://www.shadertoy.com/view/4djSRW). |
| "half hash(half3 v) {" |
| "v = fract(v*0.1031);" |
| "v += dot(v, v.zxy + 31.32);" |
| "return fract((v.x + v.y)*v.z);" |
| "}" |
| |
| // The general idea is to compute a coherent hash for two planes in discretized (x,y,e) space, |
| // and interpolate between them. This yields gradual changes when animating |e| - which is the |
| // desired outcome. |
| "half sample_noise(vec2 xy) {" |
| "xy = floor(xy);" |
| |
| "half e_ = floor(u_evolution)," |
| "t = u_evolution - e_," |
| "n0 = hash(half3(xy, e_ + 0))," |
| "n1 = hash(half3(xy, e_ + 1));" |
| |
| // Note: Ideally we would use 4 samples (-1, 0, 1, 2) and cubic interpolation for |
| // better results -- but that's significantly more expensive than lerp. |
| |
| "return mix(n0, n1, t);" |
| "}" |
| |
| // filter() placeholder |
| "%s" |
| |
| // fractal() placeholder |
| "%s" |
| |
| // Generate ceil(u_octaves) noise layers and combine based on persistentce and sublayer xform. |
| "half4 main(vec2 xy) {" |
| "half oct = u_octaves," // initial octave count (this is the effective loop counter) |
| "amp = 1," // initial layer amplitude |
| "wacc = 0," // weight accumulator |
| "n = 0;" // noise accumulator |
| |
| // Constant loop counter chosen to be >= ceil(u_octaves). |
| // The logical counter is actually 'oct'. |
| "for (half i = 0; i < %u; ++i) {" |
| // effective layer weight computed to accommodate fixed loop counters |
| // |
| // -- for full octaves: layer amplitude |
| // -- for fractional octave: layer amplitude modulated by fractional part |
| // -- for octaves > ceil(u_octaves): 0 |
| // |
| // e.g. for 6 loops and u_octaves = 2.3, this generates the sequence [1,1,.3,0,0] |
| "half w = amp*saturate(oct);" |
| |
| "n += w*fractal(filter(xy));" |
| |
| "wacc += w;" |
| "amp *= u_persistence;" |
| "oct -= 1;" |
| |
| "xy = (u_submatrix*half3(xy,1)).xy;" |
| "}" |
| |
| "n /= wacc;" |
| |
| // TODO: fractal functions |
| |
| "return half4(n,n,n,1);" |
| "}"; |
| |
| static constexpr char gFilterNearestSkSL[] = |
| "half filter(half2 xy) {" |
| "return sample_noise(xy);" |
| "}"; |
| |
| static constexpr char gFilterLinearSkSL[] = |
| "half filter(half2 xy) {" |
| "xy -= 0.5;" |
| |
| "half n00 = sample_noise(xy + half2(0,0))," |
| "n10 = sample_noise(xy + half2(1,0))," |
| "n01 = sample_noise(xy + half2(0,1))," |
| "n11 = sample_noise(xy + half2(1,1));" |
| |
| "half2 t = fract(xy);" |
| |
| "return mix(mix(n00, n10, t.x), mix(n01, n11, t.x), t.y);" |
| "}"; |
| |
| static constexpr char gFilterSoftLinearSkSL[] = |
| "half filter(half2 xy) {" |
| "xy -= 0.5;" |
| |
| "half n00 = sample_noise(xy + half2(0,0))," |
| "n10 = sample_noise(xy + half2(1,0))," |
| "n01 = sample_noise(xy + half2(0,1))," |
| "n11 = sample_noise(xy + half2(1,1));" |
| |
| "half2 t = smoothstep(0, 1, fract(xy));" |
| |
| "return mix(mix(n00, n10, t.x), mix(n01, n11, t.x), t.y);" |
| "}"; |
| |
| static constexpr char gFractalBasicSkSL[] = |
| "half fractal(half n) {" |
| "return n;" |
| "}"; |
| |
| static constexpr char gFractalTurbulentBasicSkSL[] = |
| "half fractal(half n) {" |
| "return 2*abs(0.5 - n);" |
| "}"; |
| |
| static constexpr char gFractalTurbulentSmoothSkSL[] = |
| "half fractal(half n) {" |
| "n = 2*abs(0.5 - n);" |
| "return n*n;" |
| "}"; |
| |
| static constexpr char gFractalTurbulentSharpSkSL[] = |
| "half fractal(half n) {" |
| "return sqrt(2*abs(0.5 - n));" |
| "}"; |
| |
| enum class NoiseFilter { |
| kNearest, |
| kLinear, |
| kSoftLinear, |
| // TODO: kSpline? |
| }; |
| |
| enum class NoiseFractal { |
| kBasic, |
| kTurbulentBasic, |
| kTurbulentSmooth, |
| kTurbulentSharp, |
| }; |
| |
| sk_sp<SkRuntimeEffect> make_noise_effect(unsigned loops, const char* filter, const char* fractal) { |
| auto result = |
| SkRuntimeEffect::Make(SkStringPrintf(gNoiseEffectSkSL, filter, fractal, loops), {}); |
| |
| if (0 && !result.effect) { |
| printf("!!! %s\n", result.errorText.c_str()); |
| } |
| |
| return std::move(result.effect); |
| } |
| |
| template <unsigned LOOPS, NoiseFilter FILTER, NoiseFractal FRACTAL> |
| sk_sp<SkRuntimeEffect> noise_effect() { |
| static constexpr char const* gFilters[] = { |
| gFilterNearestSkSL, |
| gFilterLinearSkSL, |
| gFilterSoftLinearSkSL |
| }; |
| |
| static constexpr char const* gFractals[] = { |
| gFractalBasicSkSL, |
| gFractalTurbulentBasicSkSL, |
| gFractalTurbulentSmoothSkSL, |
| gFractalTurbulentSharpSkSL |
| }; |
| |
| static_assert(static_cast<size_t>(FILTER) < SK_ARRAY_COUNT(gFilters)); |
| static_assert(static_cast<size_t>(FRACTAL) < SK_ARRAY_COUNT(gFractals)); |
| |
| static const SkRuntimeEffect* effect = |
| make_noise_effect(LOOPS, |
| gFilters[static_cast<size_t>(FILTER)], |
| gFractals[static_cast<size_t>(FRACTAL)]) |
| .release(); |
| |
| SkASSERT(effect); |
| return sk_ref_sp(effect); |
| } |
| |
| class FractalNoiseNode final : public sksg::CustomRenderNode { |
| public: |
| explicit FractalNoiseNode(sk_sp<RenderNode> child) : INHERITED({std::move(child)}) {} |
| |
| SG_ATTRIBUTE(Matrix , SkMatrix , fMatrix ) |
| SG_ATTRIBUTE(SubMatrix , SkMatrix , fSubMatrix ) |
| |
| SG_ATTRIBUTE(NoiseFilter , NoiseFilter , fFilter ) |
| SG_ATTRIBUTE(NoiseFractal, NoiseFractal, fFractal ) |
| SG_ATTRIBUTE(Octaves , float , fOctaves ) |
| SG_ATTRIBUTE(Persistence , float , fPersistence) |
| SG_ATTRIBUTE(Evolution , float , fEvolution ) |
| |
| private: |
| template <NoiseFilter FI, NoiseFractal FR> |
| sk_sp<SkRuntimeEffect> getEffect() const { |
| // Bin the loop counter based on the number of octaves (range: [1..20]). |
| // Low complexities are common, so we maximize resolution for the low end. |
| if (fOctaves > 8) return noise_effect<20, FI, FR>(); |
| if (fOctaves > 4) return noise_effect< 8, FI, FR>(); |
| if (fOctaves > 3) return noise_effect< 4, FI, FR>(); |
| if (fOctaves > 2) return noise_effect< 3, FI, FR>(); |
| if (fOctaves > 1) return noise_effect< 2, FI, FR>(); |
| |
| return noise_effect<1, FI, FR>(); |
| } |
| |
| template <NoiseFilter FI> |
| sk_sp<SkRuntimeEffect> getEffect() const { |
| switch (fFractal) { |
| case NoiseFractal::kBasic: |
| return this->getEffect<FI, NoiseFractal::kBasic>(); |
| case NoiseFractal::kTurbulentBasic: |
| return this->getEffect<FI, NoiseFractal::kTurbulentBasic>(); |
| case NoiseFractal::kTurbulentSmooth: |
| return this->getEffect<FI, NoiseFractal::kTurbulentSmooth>(); |
| case NoiseFractal::kTurbulentSharp: |
| return this->getEffect<FI, NoiseFractal::kTurbulentSharp>(); |
| } |
| SkUNREACHABLE; |
| } |
| |
| sk_sp<SkRuntimeEffect> getEffect() const { |
| switch (fFilter) { |
| case NoiseFilter::kNearest : return this->getEffect<NoiseFilter::kNearest>(); |
| case NoiseFilter::kLinear : return this->getEffect<NoiseFilter::kLinear>(); |
| case NoiseFilter::kSoftLinear: return this->getEffect<NoiseFilter::kSoftLinear>(); |
| } |
| SkUNREACHABLE; |
| } |
| |
| sk_sp<SkShader> buildEffectShader() const { |
| SkRuntimeShaderBuilder builder(this->getEffect()); |
| |
| builder.uniform("u_octaves") = fOctaves; |
| builder.uniform("u_persistence") = fPersistence; |
| builder.uniform("u_evolution") = fEvolution; |
| builder.uniform("u_submatrix") = std::array<float,9>{ |
| fSubMatrix.rc(0,0), fSubMatrix.rc(1,0), fSubMatrix.rc(2,0), |
| fSubMatrix.rc(0,1), fSubMatrix.rc(1,1), fSubMatrix.rc(2,1), |
| fSubMatrix.rc(0,2), fSubMatrix.rc(1,2), fSubMatrix.rc(2,2), |
| }; |
| |
| return builder.makeShader(&fMatrix, false); |
| } |
| |
| SkRect onRevalidate(sksg::InvalidationController* ic, const SkMatrix& ctm) override { |
| const auto& child = this->children()[0]; |
| const auto bounds = child->revalidate(nullptr, SkMatrix::I()); |
| |
| fEffectShader = this->buildEffectShader(); |
| |
| return bounds; |
| } |
| |
| void onRender(SkCanvas* canvas, const RenderContext* ctx) const override { |
| const auto& bounds = this->bounds(); |
| const auto local_ctx = ScopedRenderContext(canvas, ctx) |
| .setIsolation(bounds, canvas->getTotalMatrix(), true); |
| |
| canvas->saveLayer(&bounds, nullptr); |
| this->children()[0]->render(canvas, local_ctx); |
| |
| SkPaint effect_paint; |
| effect_paint.setShader(fEffectShader); |
| effect_paint.setBlendMode(SkBlendMode::kSrcIn); |
| |
| canvas->drawPaint(effect_paint); |
| } |
| |
| const RenderNode* onNodeAt(const SkPoint&) const override { return nullptr; } // no hit-testing |
| |
| sk_sp<SkShader> fEffectShader; |
| |
| SkMatrix fMatrix, |
| fSubMatrix; |
| NoiseFilter fFilter = NoiseFilter::kNearest; |
| NoiseFractal fFractal = NoiseFractal::kBasic; |
| float fOctaves = 1, |
| fPersistence = 1, |
| fEvolution = 0; |
| |
| using INHERITED = sksg::CustomRenderNode; |
| }; |
| |
| class FractalNoiseAdapter final : public DiscardableAdapterBase<FractalNoiseAdapter, |
| FractalNoiseNode> { |
| public: |
| FractalNoiseAdapter(const skjson::ArrayValue& jprops, |
| const AnimationBuilder* abuilder, |
| sk_sp<FractalNoiseNode> node) |
| : INHERITED(std::move(node)) |
| { |
| EffectBinder(jprops, *abuilder, this) |
| .bind( 0, fFractalType ) |
| .bind( 1, fNoiseType ) |
| .bind( 2, fInvert ) |
| .bind( 3, fContrast ) |
| .bind( 4, fBrightness ) |
| // 5 -- overflow |
| // 6 -- transform begin-group |
| .bind( 7, fRotation ) |
| .bind( 8, fUniformScaling ) |
| .bind( 9, fScale ) |
| .bind(10, fScaleWidth ) |
| .bind(11, fScaleHeight ) |
| .bind(12, fOffset ) |
| // 13 -- TODO: perspective offset |
| // 14 -- transform end-group |
| .bind(15, fComplexity ) |
| // 16 -- sub settings begin-group |
| .bind(17, fSubInfluence ) |
| .bind(18, fSubScale ) |
| .bind(19, fSubRotation ) |
| .bind(20, fSubOffset ) |
| // 21 -- center subscale |
| // 22 -- sub settings end-group |
| .bind(23, fEvolution ) |
| // 24 -- evolution options begin-group |
| // 25 -- cycle evolution |
| // 26 -- cycle revolution |
| .bind(27, fRandomSeed ) |
| // 28 -- evolution options end-group |
| .bind(29, fOpacity ); |
| // 30 -- TODO: blending mode |
| } |
| |
| private: |
| float evolution() const { |
| // Constant chosen to visually match AE's evolution rate. |
| const auto evo = SkDegreesToRadians(fEvolution) * 0.25f; |
| |
| // The random seed determines an arbitrary start plane. |
| const auto base = SkRandom(static_cast<uint32_t>(fRandomSeed)).nextRangeU(0, 100); |
| |
| return evo + base; |
| } |
| |
| SkMatrix shaderMatrix() const { |
| static constexpr float kGridSize = 64; |
| |
| const auto scale = (SkScalarRoundToInt(fUniformScaling) == 1) |
| ? SkV2{fScale, fScale} |
| : SkV2{fScaleWidth, fScaleHeight}; |
| |
| return SkMatrix::Translate(fOffset.x, fOffset.y) |
| * SkMatrix::RotateDeg(fRotation) |
| * SkMatrix::Scale(SkTPin(scale.x, 1.0f, 10000.0f) * 0.01f, |
| SkTPin(scale.y, 1.0f, 10000.0f) * 0.01f) |
| * SkMatrix::Scale(kGridSize, kGridSize); |
| } |
| |
| SkMatrix subMatrix() const { |
| const auto scale = 100 / SkTPin(fSubScale, 10.0f, 10000.0f); |
| |
| return SkMatrix::Translate(-fSubOffset.x * 0.01f, -fSubOffset.y * 0.01f) |
| * SkMatrix::RotateDeg(-fSubRotation) |
| * SkMatrix::Scale(scale, scale); |
| } |
| |
| NoiseFilter noiseFilter() const { |
| switch (SkScalarRoundToInt(fNoiseType)) { |
| case 1: return NoiseFilter::kNearest; |
| case 2: return NoiseFilter::kLinear; |
| default: return NoiseFilter::kSoftLinear; |
| } |
| SkUNREACHABLE; |
| } |
| |
| NoiseFractal noiseFractal() const { |
| switch (SkScalarRoundToInt(fFractalType)) { |
| case 1: return NoiseFractal::kBasic; |
| case 3: return NoiseFractal::kTurbulentSmooth; |
| case 4: return NoiseFractal::kTurbulentBasic; |
| default: return NoiseFractal::kTurbulentSharp; |
| } |
| SkUNREACHABLE; |
| } |
| |
| void onSync() override { |
| const auto& n = this->node(); |
| |
| n->setOctaves(SkTPin(fComplexity, 1.0f, 20.0f)); |
| n->setPersistence(SkTPin(fSubInfluence * 0.01f, 0.0f, 100.0f)); |
| n->setEvolution(this->evolution()); |
| n->setNoiseFilter(this->noiseFilter()); |
| n->setNoiseFractal(this->noiseFractal()); |
| n->setMatrix(this->shaderMatrix()); |
| n->setSubMatrix(this->subMatrix()); |
| } |
| |
| Vec2Value fOffset = {0,0}, |
| fSubOffset = {0,0}; |
| |
| ScalarValue fFractalType = 0, |
| fNoiseType = 0, |
| |
| fRotation = 0, |
| fUniformScaling = 0, |
| fScale = 100, // used when uniform scaling is selected |
| fScaleWidth = 100, // used when uniform scaling is not selected |
| fScaleHeight = 100, // ^ |
| |
| fComplexity = 1, |
| fSubInfluence = 100, |
| fSubScale = 50, |
| fSubRotation = 0, |
| |
| fEvolution = 0, |
| fRandomSeed = 0, |
| |
| fOpacity = 100, // TODO |
| fInvert = 0, // TODO |
| fContrast = 100, // TODO |
| fBrightness = 0; // TODO |
| |
| using INHERITED = DiscardableAdapterBase<FractalNoiseAdapter, FractalNoiseNode>; |
| }; |
| |
| } // namespace |
| |
| sk_sp<sksg::RenderNode> EffectBuilder::attachFractalNoiseEffect( |
| const skjson::ArrayValue& jprops, sk_sp<sksg::RenderNode> layer) const { |
| auto fractal_noise = sk_make_sp<FractalNoiseNode>(std::move(layer)); |
| |
| return fBuilder->attachDiscardableAdapter<FractalNoiseAdapter>(jprops, fBuilder, |
| std::move(fractal_noise)); |
| } |
| |
| } // namespace skottie::internal |
