godot/thirdparty/embree/kernels/subdiv/bezier_curve.h

// Copyright 2009-2021 Intel Corporation
// SPDX-License-Identifier: Apache-2.0

#pragma once

#include "../common/default.h"
//#include "../common/scene_curves.h"
#include "../common/context.h"

namespace embree
{
  class BezierBasis
  { … };
  
  struct PrecomputedBezierBasis
  { … };
  extern PrecomputedBezierBasis bezier_basis0;
  extern PrecomputedBezierBasis bezier_basis1;

  
  template<typename V>
    struct LinearBezierCurve
    { … };
  
  template<> __forceinline bool LinearBezierCurve<Interval1f>::hasRoot() const { … }
  
  template<typename V>
    struct QuadraticBezierCurve
    { … };
  
  
  QuadraticBezierCurve1f;
  QuadraticBezierCurve2fa;
  QuadraticBezierCurve3fa;

  template<typename Vertex>
    struct CubicBezierCurve
    { … };

#if defined(__AVX__)
  template<>
    __forceinline CubicBezierCurve<vfloat4> CubicBezierCurve<vfloat4>::clip(const Interval1f& u1) const
  {
    const vfloat8 p00 = vfloat8(v0);
    const vfloat8 p01 = vfloat8(v1);
    const vfloat8 p02 = vfloat8(v2);
    const vfloat8 p03 = vfloat8(v3);

    const vfloat8 t(vfloat4(u1.lower),vfloat4(u1.upper));
    const vfloat8 p10 = lerp(p00,p01,t);
    const vfloat8 p11 = lerp(p01,p02,t);
    const vfloat8 p12 = lerp(p02,p03,t);
    const vfloat8 p20 = lerp(p10,p11,t);
    const vfloat8 p21 = lerp(p11,p12,t);
    const vfloat8 p30 = lerp(p20,p21,t);
    
    const vfloat8 f01  = p30;
    const vfloat8 df01 = vfloat8(3.0f)*(p21-p20);
        
    const vfloat4 f0  = extract4<0>(f01),  f1  = extract4<1>(f01);
    const vfloat4 df0 = extract4<0>(df01), df1 = extract4<1>(df01);
    const float s = u1.upper-u1.lower;
    return CubicBezierCurve(f0,f0+s*(1.0f/3.0f)*df0,f1-s*(1.0f/3.0f)*df1,f1);
  }
#endif
  
  BezierCurveT;
  
  CubicBezierCurve1f;
  CubicBezierCurve2fa;
  CubicBezierCurve3fa;
  BezierCurve3fa;
  BezierCurve3ff;
  
  template<> __forceinline int CubicBezierCurve<float>::maxRoots() const
  { … }
  
  template<> __forceinline int CubicBezierCurve<Interval1f>::maxRoots() const { … }

  struct CurveGeometry; // FIXME: this code should move !
  template<typename CurveGeometry>
  __forceinline CubicBezierCurve<Vec3ff> enlargeRadiusToMinWidth(const RayQueryContext* context, const CurveGeometry* geom, const Vec3fa& ray_org, const CubicBezierCurve<Vec3ff>& curve)
  { … }
}