chromium/third_party/skia/modules/skottie/src/effects/FractalNoiseEffect.cpp

/*
 * 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 "include/core/SkBlendMode.h"
#include "include/core/SkCanvas.h"
#include "include/core/SkM44.h"
#include "include/core/SkMatrix.h"
#include "include/core/SkPaint.h"
#include "include/core/SkRect.h"
#include "include/core/SkRefCnt.h"
#include "include/core/SkScalar.h"
#include "include/core/SkShader.h"
#include "include/core/SkString.h"
#include "include/effects/SkRuntimeEffect.h"
#include "include/private/base/SkAssert.h"
#include "include/private/base/SkFloatingPoint.h"
#include "include/private/base/SkTPin.h"
#include "modules/skottie/src/Adapter.h"
#include "modules/skottie/src/SkottiePriv.h"
#include "modules/skottie/src/SkottieValue.h"
#include "modules/skottie/src/effects/Effects.h"
#include "modules/sksg/include/SkSGNode.h"
#include "modules/sksg/include/SkSGRenderNode.h"
#include "src/base/SkRandom.h"

#include <algorithm>
#include <array>
#include <cmath>
#include <cstddef>
#include <cstdint>
#include <tuple>
#include <utility>
#include <vector>

struct SkPoint;

namespace skjson {
class ArrayValue;
}
namespace sksg {
class InvalidationController;
}

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[] = …;

static constexpr char gFilterNearestSkSL[] = …;

static constexpr char gFilterLinearSkSL[] = …;

static constexpr char gFilterSoftLinearSkSL[] = …;

static constexpr char gFractalBasicSkSL[] = …;

static constexpr char gFractalTurbulentBasicSkSL[] = …;

static constexpr char gFractalTurbulentSmoothSkSL[] = …;

static constexpr char gFractalTurbulentSharpSkSL[] = …;

enum class NoiseFilter { … };

enum class NoiseFractal { … };

sk_sp<SkRuntimeEffect> make_noise_effect(unsigned loops, const char* filter, const char* fractal) { … }

sk_sp<SkRuntimeEffect> noise_effect(float octaves, NoiseFilter filter, NoiseFractal fractal) { … }

class FractalNoiseNode final : public sksg::CustomRenderNode { … };

class FractalNoiseAdapter final : public DiscardableAdapterBase<FractalNoiseAdapter,
                                                                FractalNoiseNode> { … };

} // namespace

sk_sp<sksg::RenderNode> EffectBuilder::attachFractalNoiseEffect(
        const skjson::ArrayValue& jprops, sk_sp<sksg::RenderNode> layer) const { … }

} // namespace skottie::internal