virtualx-engine/thirdparty/embree/kernels/subdiv/bezier_curve.h
Jakub Mateusz Marcowski c43eab55a4
embree: Update to 4.3.1
2024-03-27 22:10:35 +01:00

729 lines
27 KiB
C++

// 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
{
public:
template<typename T>
static __forceinline Vec4<T> eval(const T& u)
{
const T t1 = u;
const T t0 = 1.0f-t1;
const T B0 = t0 * t0 * t0;
const T B1 = 3.0f * t1 * (t0 * t0);
const T B2 = 3.0f * (t1 * t1) * t0;
const T B3 = t1 * t1 * t1;
return Vec4<T>(B0,B1,B2,B3);
}
template<typename T>
static __forceinline Vec4<T> derivative(const T& u)
{
const T t1 = u;
const T t0 = 1.0f-t1;
const T B0 = -(t0*t0);
const T B1 = madd(-2.0f,t0*t1,t0*t0);
const T B2 = msub(+2.0f,t0*t1,t1*t1);
const T B3 = +(t1*t1);
return T(3.0f)*Vec4<T>(B0,B1,B2,B3);
}
template<typename T>
static __forceinline Vec4<T> derivative2(const T& u)
{
const T t1 = u;
const T t0 = 1.0f-t1;
const T B0 = t0;
const T B1 = madd(-2.0f,t0,t1);
const T B2 = madd(-2.0f,t1,t0);
const T B3 = t1;
return T(6.0f)*Vec4<T>(B0,B1,B2,B3);
}
};
struct PrecomputedBezierBasis
{
enum { N = 16 };
public:
PrecomputedBezierBasis() {}
PrecomputedBezierBasis(int shift);
/* basis for bezier evaluation */
public:
float c0[N+1][N+1];
float c1[N+1][N+1];
float c2[N+1][N+1];
float c3[N+1][N+1];
/* basis for bezier derivative evaluation */
public:
float d0[N+1][N+1];
float d1[N+1][N+1];
float d2[N+1][N+1];
float d3[N+1][N+1];
};
extern PrecomputedBezierBasis bezier_basis0;
extern PrecomputedBezierBasis bezier_basis1;
template<typename V>
struct LinearBezierCurve
{
V v0,v1;
__forceinline LinearBezierCurve () {}
__forceinline LinearBezierCurve (const LinearBezierCurve& other)
: v0(other.v0), v1(other.v1) {}
__forceinline LinearBezierCurve& operator= (const LinearBezierCurve& other) {
v0 = other.v0; v1 = other.v1; return *this;
}
__forceinline LinearBezierCurve (const V& v0, const V& v1)
: v0(v0), v1(v1) {}
__forceinline V begin() const { return v0; }
__forceinline V end () const { return v1; }
bool hasRoot() const;
friend embree_ostream operator<<(embree_ostream cout, const LinearBezierCurve& a) {
return cout << "LinearBezierCurve (" << a.v0 << ", " << a.v1 << ")";
}
};
template<> __forceinline bool LinearBezierCurve<Interval1f>::hasRoot() const {
return numRoots(v0,v1);
}
template<typename V>
struct QuadraticBezierCurve
{
V v0,v1,v2;
__forceinline QuadraticBezierCurve () {}
__forceinline QuadraticBezierCurve (const QuadraticBezierCurve& other)
: v0(other.v0), v1(other.v1), v2(other.v2) {}
__forceinline QuadraticBezierCurve& operator= (const QuadraticBezierCurve& other) {
v0 = other.v0; v1 = other.v1; v2 = other.v2; return *this;
}
__forceinline QuadraticBezierCurve (const V& v0, const V& v1, const V& v2)
: v0(v0), v1(v1), v2(v2) {}
__forceinline V begin() const { return v0; }
__forceinline V end () const { return v2; }
__forceinline V interval() const {
return merge(v0,v1,v2);
}
__forceinline BBox<V> bounds() const {
return merge(BBox<V>(v0),BBox<V>(v1),BBox<V>(v2));
}
friend embree_ostream operator<<(embree_ostream cout, const QuadraticBezierCurve& a) {
return cout << "QuadraticBezierCurve ( (" << a.u.lower << ", " << a.u.upper << "), " << a.v0 << ", " << a.v1 << ", " << a.v2 << ")";
}
};
typedef QuadraticBezierCurve<float> QuadraticBezierCurve1f;
typedef QuadraticBezierCurve<Vec2fa> QuadraticBezierCurve2fa;
typedef QuadraticBezierCurve<Vec3fa> QuadraticBezierCurve3fa;
template<typename Vertex>
struct CubicBezierCurve
{
Vertex v0,v1,v2,v3;
__forceinline CubicBezierCurve() {}
template<typename T1>
__forceinline CubicBezierCurve (const CubicBezierCurve<T1>& other)
: v0(other.v0), v1(other.v1), v2(other.v2), v3(other.v3) {}
__forceinline CubicBezierCurve& operator= (const CubicBezierCurve& other) {
v0 = other.v0; v1 = other.v1; v2 = other.v2; v3 = other.v3; return *this;
}
__forceinline CubicBezierCurve(const Vertex& v0, const Vertex& v1, const Vertex& v2, const Vertex& v3)
: v0(v0), v1(v1), v2(v2), v3(v3) {}
__forceinline Vertex begin() const {
return v0;
}
__forceinline Vertex end() const {
return v3;
}
__forceinline Vertex center() const {
return 0.25f*(v0+v1+v2+v3);
}
__forceinline Vertex begin_direction() const {
return v1-v0;
}
__forceinline Vertex end_direction() const {
return v3-v2;
}
__forceinline CubicBezierCurve<float> xfm(const Vertex& dx) const {
return CubicBezierCurve<float>(dot(v0,dx),dot(v1,dx),dot(v2,dx),dot(v3,dx));
}
template<int W>
__forceinline CubicBezierCurve<vfloat<W>> vxfm(const Vertex& dx) const {
return CubicBezierCurve<vfloat<W>>(dot(v0,dx),dot(v1,dx),dot(v2,dx),dot(v3,dx));
}
__forceinline CubicBezierCurve<float> xfm(const Vertex& dx, const Vertex& p) const {
return CubicBezierCurve<float>(dot(v0-p,dx),dot(v1-p,dx),dot(v2-p,dx),dot(v3-p,dx));
}
__forceinline CubicBezierCurve<Vec3fa> xfm(const LinearSpace3fa& space) const
{
const Vec3fa q0 = xfmVector(space,v0);
const Vec3fa q1 = xfmVector(space,v1);
const Vec3fa q2 = xfmVector(space,v2);
const Vec3fa q3 = xfmVector(space,v3);
return CubicBezierCurve<Vec3fa>(q0,q1,q2,q3);
}
__forceinline CubicBezierCurve<Vec3fa> xfm(const LinearSpace3fa& space, const Vec3fa& p) const
{
const Vec3fa q0 = xfmVector(space,v0-p);
const Vec3fa q1 = xfmVector(space,v1-p);
const Vec3fa q2 = xfmVector(space,v2-p);
const Vec3fa q3 = xfmVector(space,v3-p);
return CubicBezierCurve<Vec3fa>(q0,q1,q2,q3);
}
__forceinline CubicBezierCurve<Vec3ff> xfm_pr(const LinearSpace3fa& space, const Vec3fa& p) const
{
const Vec3ff q0(xfmVector(space,(Vec3fa)v0-p), v0.w);
const Vec3ff q1(xfmVector(space,(Vec3fa)v1-p), v1.w);
const Vec3ff q2(xfmVector(space,(Vec3fa)v2-p), v2.w);
const Vec3ff q3(xfmVector(space,(Vec3fa)v3-p), v3.w);
return CubicBezierCurve<Vec3ff>(q0,q1,q2,q3);
}
__forceinline CubicBezierCurve<Vec3fa> xfm(const LinearSpace3fa& space, const Vec3fa& p, const float s) const
{
const Vec3fa q0 = xfmVector(space,s*(v0-p));
const Vec3fa q1 = xfmVector(space,s*(v1-p));
const Vec3fa q2 = xfmVector(space,s*(v2-p));
const Vec3fa q3 = xfmVector(space,s*(v3-p));
return CubicBezierCurve<Vec3fa>(q0,q1,q2,q3);
}
__forceinline int maxRoots() const;
__forceinline BBox<Vertex> bounds() const {
return merge(BBox<Vertex>(v0),BBox<Vertex>(v1),BBox<Vertex>(v2),BBox<Vertex>(v3));
}
__forceinline friend CubicBezierCurve operator +( const CubicBezierCurve& a, const CubicBezierCurve& b ) {
return CubicBezierCurve(a.v0+b.v0,a.v1+b.v1,a.v2+b.v2,a.v3+b.v3);
}
__forceinline friend CubicBezierCurve operator -( const CubicBezierCurve& a, const CubicBezierCurve& b ) {
return CubicBezierCurve(a.v0-b.v0,a.v1-b.v1,a.v2-b.v2,a.v3-b.v3);
}
__forceinline friend CubicBezierCurve operator -( const CubicBezierCurve& a, const Vertex& b ) {
return CubicBezierCurve(a.v0-b,a.v1-b,a.v2-b,a.v3-b);
}
__forceinline friend CubicBezierCurve operator *( const Vertex& a, const CubicBezierCurve& b ) {
return CubicBezierCurve(a*b.v0,a*b.v1,a*b.v2,a*b.v3);
}
__forceinline friend CubicBezierCurve cmadd( const Vertex& a, const CubicBezierCurve& b, const CubicBezierCurve& c) {
return CubicBezierCurve(madd(a,b.v0,c.v0),madd(a,b.v1,c.v1),madd(a,b.v2,c.v2),madd(a,b.v3,c.v3));
}
__forceinline friend CubicBezierCurve clerp ( const CubicBezierCurve& a, const CubicBezierCurve& b, const Vertex& t ) {
return cmadd((Vertex(1.0f)-t),a,t*b);
}
__forceinline friend CubicBezierCurve merge ( const CubicBezierCurve& a, const CubicBezierCurve& b ) {
return CubicBezierCurve(merge(a.v0,b.v0),merge(a.v1,b.v1),merge(a.v2,b.v2),merge(a.v3,b.v3));
}
__forceinline void split(CubicBezierCurve& left, CubicBezierCurve& right, const float t = 0.5f) const
{
const Vertex p00 = v0;
const Vertex p01 = v1;
const Vertex p02 = v2;
const Vertex p03 = v3;
const Vertex p10 = lerp(p00,p01,t);
const Vertex p11 = lerp(p01,p02,t);
const Vertex p12 = lerp(p02,p03,t);
const Vertex p20 = lerp(p10,p11,t);
const Vertex p21 = lerp(p11,p12,t);
const Vertex p30 = lerp(p20,p21,t);
new (&left ) CubicBezierCurve(p00,p10,p20,p30);
new (&right) CubicBezierCurve(p30,p21,p12,p03);
}
__forceinline CubicBezierCurve<Vec2vfx> split() const
{
const float u0 = 0.0f, u1 = 1.0f;
const float dscale = (u1-u0)*(1.0f/(3.0f*(VSIZEX-1)));
const vfloatx vu0 = lerp(u0,u1,vfloatx(StepTy())*(1.0f/(VSIZEX-1)));
Vec2vfx P0, dP0du; evalN(vu0,P0,dP0du); dP0du = dP0du * Vec2vfx(dscale);
const Vec2vfx P3 = shift_right_1(P0);
const Vec2vfx dP3du = shift_right_1(dP0du);
const Vec2vfx P1 = P0 + dP0du;
const Vec2vfx P2 = P3 - dP3du;
return CubicBezierCurve<Vec2vfx>(P0,P1,P2,P3);
}
__forceinline CubicBezierCurve<Vec2vfx> split(const BBox1f& u) const
{
const float u0 = u.lower, u1 = u.upper;
const float dscale = (u1-u0)*(1.0f/(3.0f*(VSIZEX-1)));
const vfloatx vu0 = lerp(u0,u1,vfloatx(StepTy())*(1.0f/(VSIZEX-1)));
Vec2vfx P0, dP0du; evalN(vu0,P0,dP0du); dP0du = dP0du * Vec2vfx(dscale);
const Vec2vfx P3 = shift_right_1(P0);
const Vec2vfx dP3du = shift_right_1(dP0du);
const Vec2vfx P1 = P0 + dP0du;
const Vec2vfx P2 = P3 - dP3du;
return CubicBezierCurve<Vec2vfx>(P0,P1,P2,P3);
}
template<int W>
__forceinline CubicBezierCurve<Vec2vf<W>> split(const BBox1f& u, int i, int N) const
{
const float u0 = u.lower, u1 = u.upper;
const float dscale = (u1-u0)*(1.0f/(3.0f*N));
const vfloat<W> vu0 = lerp(u0,u1,(vfloat<W>(i)+vfloat<W>(StepTy()))*(1.0f/N));
Vec2vf<W> P0, dP0du; evalN(vu0,P0,dP0du); dP0du = dP0du * Vec2vf<W>(dscale);
const Vec2vf<W> P3 = shift_right_1(P0);
const Vec2vf<W> dP3du = shift_right_1(dP0du);
const Vec2vf<W> P1 = P0 + dP0du;
const Vec2vf<W> P2 = P3 - dP3du;
return CubicBezierCurve<Vec2vf<W>>(P0,P1,P2,P3);
}
__forceinline CubicBezierCurve<Vec2f> split1(const BBox1f& u, int i, int N) const
{
const float u0 = u.lower, u1 = u.upper;
const float dscale = (u1-u0)*(1.0f/(3.0f*N));
const float vu0 = lerp(u0,u1,(float(i)+0)*(1.0f/N));
const float vu1 = lerp(u0,u1,(float(i)+1)*(1.0f/N));
Vec2fa P0, dP0du; eval(vu0,P0,dP0du); dP0du = dP0du * Vec2fa(dscale);
Vec2fa P3, dP3du; eval(vu1,P3,dP3du); dP3du = dP3du * Vec2fa(dscale);
const Vec2fa P1 = P0 + dP0du;
const Vec2fa P2 = P3 - dP3du;
return CubicBezierCurve<Vec2f>(P0,P1,P2,P3);
}
__forceinline void eval(float t, Vertex& p, Vertex& dp) const
{
const Vertex p00 = v0;
const Vertex p01 = v1;
const Vertex p02 = v2;
const Vertex p03 = v3;
const Vertex p10 = lerp(p00,p01,t);
const Vertex p11 = lerp(p01,p02,t);
const Vertex p12 = lerp(p02,p03,t);
const Vertex p20 = lerp(p10,p11,t);
const Vertex p21 = lerp(p11,p12,t);
const Vertex p30 = lerp(p20,p21,t);
p = p30;
dp = Vertex(3.0f)*(p21-p20);
}
#if 0
__forceinline Vertex eval(float t) const
{
const Vertex p00 = v0;
const Vertex p01 = v1;
const Vertex p02 = v2;
const Vertex p03 = v3;
const Vertex p10 = lerp(p00,p01,t);
const Vertex p11 = lerp(p01,p02,t);
const Vertex p12 = lerp(p02,p03,t);
const Vertex p20 = lerp(p10,p11,t);
const Vertex p21 = lerp(p11,p12,t);
const Vertex p30 = lerp(p20,p21,t);
return p30;
}
#else
__forceinline Vertex eval(const float t) const
{
const Vec4<float> b = BezierBasis::eval(t);
return madd(b.x,v0,madd(b.y,v1,madd(b.z,v2,b.w*v3)));
}
#endif
__forceinline Vertex eval_dt(float t) const
{
const Vertex p00 = v1-v0;
const Vertex p01 = v2-v1;
const Vertex p02 = v3-v2;
const Vertex p10 = lerp(p00,p01,t);
const Vertex p11 = lerp(p01,p02,t);
const Vertex p20 = lerp(p10,p11,t);
return Vertex(3.0f)*p20;
}
__forceinline Vertex eval_du(const float t) const
{
const Vec4<float> b = BezierBasis::derivative(t);
return madd(b.x,v0,madd(b.y,v1,madd(b.z,v2,b.w*v3)));
}
__forceinline Vertex eval_dudu(const float t) const
{
const Vec4<float> b = BezierBasis::derivative2(t);
return madd(b.x,v0,madd(b.y,v1,madd(b.z,v2,b.w*v3)));
}
__forceinline void evalN(const vfloatx& t, Vec2vfx& p, Vec2vfx& dp) const
{
const Vec2vfx p00 = v0;
const Vec2vfx p01 = v1;
const Vec2vfx p02 = v2;
const Vec2vfx p03 = v3;
const Vec2vfx p10 = lerp(p00,p01,t);
const Vec2vfx p11 = lerp(p01,p02,t);
const Vec2vfx p12 = lerp(p02,p03,t);
const Vec2vfx p20 = lerp(p10,p11,t);
const Vec2vfx p21 = lerp(p11,p12,t);
const Vec2vfx p30 = lerp(p20,p21,t);
p = p30;
dp = vfloatx(3.0f)*(p21-p20);
}
__forceinline void eval(const float t, Vertex& p, Vertex& dp, Vertex& ddp) const
{
const Vertex p00 = v0;
const Vertex p01 = v1;
const Vertex p02 = v2;
const Vertex p03 = v3;
const Vertex p10 = lerp(p00,p01,t);
const Vertex p11 = lerp(p01,p02,t);
const Vertex p12 = lerp(p02,p03,t);
const Vertex p20 = lerp(p10,p11,t);
const Vertex p21 = lerp(p11,p12,t);
const Vertex p30 = lerp(p20,p21,t);
p = p30;
dp = 3.0f*(p21-p20);
ddp = eval_dudu(t);
}
__forceinline CubicBezierCurve clip(const Interval1f& u1) const
{
Vertex f0,df0; eval(u1.lower,f0,df0);
Vertex f1,df1; eval(u1.upper,f1,df1);
float s = u1.upper-u1.lower;
return CubicBezierCurve(f0,f0+s*(1.0f/3.0f)*df0,f1-s*(1.0f/3.0f)*df1,f1);
}
__forceinline QuadraticBezierCurve<Vertex> derivative() const
{
const Vertex q0 = 3.0f*(v1-v0);
const Vertex q1 = 3.0f*(v2-v1);
const Vertex q2 = 3.0f*(v3-v2);
return QuadraticBezierCurve<Vertex>(q0,q1,q2);
}
__forceinline BBox<Vertex> derivative_bounds(const Interval1f& u1) const
{
Vertex f0,df0; eval(u1.lower,f0,df0);
Vertex f3,df3; eval(u1.upper,f3,df3);
const float s = u1.upper-u1.lower;
const Vertex f1 = f0+s*(1.0f/3.0f)*df0;
const Vertex f2 = f3-s*(1.0f/3.0f)*df3;
const Vertex q0 = s*df0;
const Vertex q1 = 3.0f*(f2-f1);
const Vertex q2 = s*df3;
return merge(BBox<Vertex>(q0),BBox<Vertex>(q1),BBox<Vertex>(q2));
}
template<int M>
__forceinline Vec4vf<M> veval(const vfloat<M>& t) const
{
const Vec4vf<M> b = BezierBasis::eval(t);
return madd(b.x, Vec4vf<M>(v0), madd(b.y, Vec4vf<M>(v1), madd(b.z, Vec4vf<M>(v2), b.w * Vec4vf<M>(v3))));
}
template<int M>
__forceinline Vec4vf<M> veval_du(const vfloat<M>& t) const
{
const Vec4vf<M> b = BezierBasis::derivative(t);
return madd(b.x, Vec4vf<M>(v0), madd(b.y, Vec4vf<M>(v1), madd(b.z, Vec4vf<M>(v2), b.w * Vec4vf<M>(v3))));
}
template<int M>
__forceinline Vec4vf<M> veval_dudu(const vfloat<M>& t) const
{
const Vec4vf<M> b = BezierBasis::derivative2(t);
return madd(b.x, Vec4vf<M>(v0), madd(b.y, Vec4vf<M>(v1), madd(b.z, Vec4vf<M>(v2), b.w * Vec4vf<M>(v3))));
}
template<int M, typename Vec>
__forceinline void veval(const vfloat<M>& t, Vec& p, Vec& dp) const
{
const Vec p00 = v0;
const Vec p01 = v1;
const Vec p02 = v2;
const Vec p03 = v3;
const Vec p10 = lerp(p00,p01,t);
const Vec p11 = lerp(p01,p02,t);
const Vec p12 = lerp(p02,p03,t);
const Vec p20 = lerp(p10,p11,t);
const Vec p21 = lerp(p11,p12,t);
const Vec p30 = lerp(p20,p21,t);
p = p30;
dp = vfloat<M>(3.0f)*(p21-p20);
}
template<int M, typename Vec = Vec4vf<M>>
__forceinline Vec eval0(const int ofs, const int size) const
{
assert(size <= PrecomputedBezierBasis::N);
assert(ofs <= size);
#if defined(EMBREE_SYCL_SUPPORT) && defined(__SYCL_DEVICE_ONLY__)
assert(size > 0);
const vfloat<M> t = (vfloat<M>(step) + vfloat<M>(ofs+0))*rcp(float(size));
Vec p,dp; veval<M>(t,p,dp);
return p;
#else
return madd(vfloat<M>::loadu(&bezier_basis0.c0[size][ofs]), Vec(v0),
madd(vfloat<M>::loadu(&bezier_basis0.c1[size][ofs]), Vec(v1),
madd(vfloat<M>::loadu(&bezier_basis0.c2[size][ofs]), Vec(v2),
vfloat<M>::loadu(&bezier_basis0.c3[size][ofs]) * Vec(v3))));
#endif
}
template<int M, typename Vec = Vec4vf<M>>
__forceinline Vec eval1(const int ofs, const int size) const
{
assert(size <= PrecomputedBezierBasis::N);
assert(ofs <= size);
#if defined(EMBREE_SYCL_SUPPORT) && defined(__SYCL_DEVICE_ONLY__)
assert(size > 0);
const vfloat<M> t = (vfloat<M>(step) + vfloat<M>(ofs+1))*rcp(float(size));
Vec p,dp; veval<M>(t,p,dp);
return p;
#else
return madd(vfloat<M>::loadu(&bezier_basis1.c0[size][ofs]), Vec(v0),
madd(vfloat<M>::loadu(&bezier_basis1.c1[size][ofs]), Vec(v1),
madd(vfloat<M>::loadu(&bezier_basis1.c2[size][ofs]), Vec(v2),
vfloat<M>::loadu(&bezier_basis1.c3[size][ofs]) * Vec(v3))));
#endif
}
template<int M, typename Vec = Vec4vf<M>>
__forceinline Vec derivative0(const int ofs, const int size) const
{
assert(size <= PrecomputedBezierBasis::N);
assert(ofs <= size);
#if defined(EMBREE_SYCL_SUPPORT) && defined(__SYCL_DEVICE_ONLY__)
assert(size > 0);
const vfloat<M> t = (vfloat<M>(step) + vfloat<M>(ofs+0))*rcp(float(size));
Vec p,dp; veval<M>(t,p,dp);
return dp;
#else
return madd(vfloat<M>::loadu(&bezier_basis0.d0[size][ofs]), Vec(v0),
madd(vfloat<M>::loadu(&bezier_basis0.d1[size][ofs]), Vec(v1),
madd(vfloat<M>::loadu(&bezier_basis0.d2[size][ofs]), Vec(v2),
vfloat<M>::loadu(&bezier_basis0.d3[size][ofs]) * Vec(v3))));
#endif
}
template<int M, typename Vec = Vec4vf<M>>
__forceinline Vec derivative1(const int ofs, const int size) const
{
assert(size <= PrecomputedBezierBasis::N);
assert(ofs <= size);
#if defined(EMBREE_SYCL_SUPPORT) && defined(__SYCL_DEVICE_ONLY__)
assert(size > 0);
const vfloat<M> t = (vfloat<M>(step) + vfloat<M>(ofs+1))*rcp(float(size));
Vec p,dp; veval<M>(t,p,dp);
return dp;
#else
return madd(vfloat<M>::loadu(&bezier_basis1.d0[size][ofs]), Vec(v0),
madd(vfloat<M>::loadu(&bezier_basis1.d1[size][ofs]), Vec(v1),
madd(vfloat<M>::loadu(&bezier_basis1.d2[size][ofs]), Vec(v2),
vfloat<M>::loadu(&bezier_basis1.d3[size][ofs]) * Vec(v3))));
#endif
}
/* calculates bounds of bezier curve geometry */
__forceinline BBox3fa accurateBounds() const
{
const int N = 7;
const float scale = 1.0f/(3.0f*(N-1));
Vec3vfx pl(pos_inf), pu(neg_inf);
for (int i=0; i<=N; i+=VSIZEX)
{
vintx vi = vintx(i)+vintx(StepTy());
vboolx valid = vi <= vintx(N);
const Vec3vfx p = eval0<VSIZEX,Vec3vf<VSIZEX>>(i,N);
const Vec3vfx dp = derivative0<VSIZEX,Vec3vf<VSIZEX>>(i,N);
const Vec3vfx pm = p-Vec3vfx(scale)*select(vi!=vintx(0),dp,Vec3vfx(zero));
const Vec3vfx pp = p+Vec3vfx(scale)*select(vi!=vintx(N),dp,Vec3vfx(zero));
pl = select(valid,min(pl,p,pm,pp),pl); // FIXME: use masked min
pu = select(valid,max(pu,p,pm,pp),pu); // FIXME: use masked min
}
const Vec3fa lower(reduce_min(pl.x),reduce_min(pl.y),reduce_min(pl.z));
const Vec3fa upper(reduce_max(pu.x),reduce_max(pu.y),reduce_max(pu.z));
return BBox3fa(lower,upper);
}
/* calculates bounds of bezier curve geometry */
__forceinline BBox3fa accurateRoundBounds() const
{
const int N = 7;
const float scale = 1.0f/(3.0f*(N-1));
Vec4vfx pl(pos_inf), pu(neg_inf);
for (int i=0; i<=N; i+=VSIZEX)
{
vintx vi = vintx(i)+vintx(StepTy());
vboolx valid = vi <= vintx(N);
const Vec4vfx p = eval0<VSIZEX>(i,N);
const Vec4vfx dp = derivative0<VSIZEX>(i,N);
const Vec4vfx pm = p-Vec4vfx(scale)*select(vi!=vintx(0),dp,Vec4vfx(zero));
const Vec4vfx pp = p+Vec4vfx(scale)*select(vi!=vintx(N),dp,Vec4vfx(zero));
pl = select(valid,min(pl,p,pm,pp),pl); // FIXME: use masked min
pu = select(valid,max(pu,p,pm,pp),pu); // FIXME: use masked min
}
const Vec3fa lower(reduce_min(pl.x),reduce_min(pl.y),reduce_min(pl.z));
const Vec3fa upper(reduce_max(pu.x),reduce_max(pu.y),reduce_max(pu.z));
const float r_min = reduce_min(pl.w);
const float r_max = reduce_max(pu.w);
const Vec3fa upper_r = Vec3fa(max(abs(r_min),abs(r_max)));
return enlarge(BBox3fa(lower,upper),upper_r);
}
/* calculates bounds when tessellated into N line segments */
__forceinline BBox3fa accurateFlatBounds(int N) const
{
if (likely(N == 4))
{
const Vec4vf4 pi = eval0<4>(0,4);
const Vec3fa lower(reduce_min(pi.x),reduce_min(pi.y),reduce_min(pi.z));
const Vec3fa upper(reduce_max(pi.x),reduce_max(pi.y),reduce_max(pi.z));
const Vec3fa upper_r = Vec3fa(reduce_max(abs(pi.w)));
return enlarge(BBox3fa(min(lower,v3),max(upper,v3)),max(upper_r,Vec3fa(abs(v3.w))));
}
else
{
Vec3vfx pl(pos_inf), pu(neg_inf); vfloatx ru(0.0f);
for (int i=0; i<N; i+=VSIZEX)
{
vboolx valid = vintx(i)+vintx(StepTy()) < vintx(N);
const Vec4vfx pi = eval0<VSIZEX>(i,N);
pl.x = select(valid,min(pl.x,pi.x),pl.x); // FIXME: use masked min
pl.y = select(valid,min(pl.y,pi.y),pl.y);
pl.z = select(valid,min(pl.z,pi.z),pl.z);
pu.x = select(valid,max(pu.x,pi.x),pu.x); // FIXME: use masked min
pu.y = select(valid,max(pu.y,pi.y),pu.y);
pu.z = select(valid,max(pu.z,pi.z),pu.z);
ru = select(valid,max(ru,abs(pi.w)),ru);
}
const Vec3fa lower(reduce_min(pl.x),reduce_min(pl.y),reduce_min(pl.z));
const Vec3fa upper(reduce_max(pu.x),reduce_max(pu.y),reduce_max(pu.z));
const Vec3fa upper_r(reduce_max(ru));
return enlarge(BBox3fa(min(lower,v3),max(upper,v3)),max(upper_r,Vec3fa(abs(v3.w))));
}
}
friend __forceinline embree_ostream operator<<(embree_ostream cout, const CubicBezierCurve& curve) {
return cout << "CubicBezierCurve { v0 = " << curve.v0 << ", v1 = " << curve.v1 << ", v2 = " << curve.v2 << ", v3 = " << curve.v3 << " }";
}
};
#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
template<typename Vertex> using BezierCurveT = CubicBezierCurve<Vertex>;
typedef CubicBezierCurve<float> CubicBezierCurve1f;
typedef CubicBezierCurve<Vec2fa> CubicBezierCurve2fa;
typedef CubicBezierCurve<Vec3fa> CubicBezierCurve3fa;
typedef CubicBezierCurve<Vec3fa> BezierCurve3fa;
typedef CubicBezierCurve<Vec3ff> BezierCurve3ff;
template<> __forceinline int CubicBezierCurve<float>::maxRoots() const
{
float eps = 1E-4f;
bool neg0 = v0 <= 0.0f; bool zero0 = fabs(v0) < eps;
bool neg1 = v1 <= 0.0f; bool zero1 = fabs(v1) < eps;
bool neg2 = v2 <= 0.0f; bool zero2 = fabs(v2) < eps;
bool neg3 = v3 <= 0.0f; bool zero3 = fabs(v3) < eps;
return (neg0 != neg1 || zero0) + (neg1 != neg2 || zero1) + (neg2 != neg3 || zero2 || zero3);
}
template<> __forceinline int CubicBezierCurve<Interval1f>::maxRoots() const {
return numRoots(v0,v1) + numRoots(v1,v2) + numRoots(v2,v3);
}
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)
{
return CubicBezierCurve<Vec3ff>(enlargeRadiusToMinWidth(context,geom,ray_org,curve.v0),
enlargeRadiusToMinWidth(context,geom,ray_org,curve.v1),
enlargeRadiusToMinWidth(context,geom,ray_org,curve.v2),
enlargeRadiusToMinWidth(context,geom,ray_org,curve.v3));
}
}