1// Copyright 2009-2021 Intel Corporation
2// SPDX-License-Identifier: Apache-2.0
3
4#pragma once
5
6#include "../common/ray.h"
7#include "curve_intersector_precalculations.h"
8
9namespace embree
10{
11 namespace isa
12 {
13 namespace __coneline_internal
14 {
15 template<int M, typename Epilog, typename ray_tfar_func>
16 static __forceinline bool intersectCone(const vbool<M>& valid_i,
17 const Vec3vf<M>& ray_org_in, const Vec3vf<M>& ray_dir,
18 const vfloat<M>& ray_tnear, const ray_tfar_func& ray_tfar,
19 const Vec4vf<M>& v0, const Vec4vf<M>& v1,
20 const vbool<M>& cL, const vbool<M>& cR,
21 const Epilog& epilog)
22 {
23 vbool<M> valid = valid_i;
24
25 /* move ray origin closer to make calculations numerically stable */
26 const vfloat<M> dOdO = sqr(ray_dir);
27 const vfloat<M> rcp_dOdO = rcp(dOdO);
28 const Vec3vf<M> center = vfloat<M>(0.5f)*(v0.xyz()+v1.xyz());
29 const vfloat<M> dt = dot(center-ray_org_in,ray_dir)*rcp_dOdO;
30 const Vec3vf<M> ray_org = ray_org_in + dt*ray_dir;
31
32 const Vec3vf<M> dP = v1.xyz() - v0.xyz();
33 const Vec3vf<M> p0 = ray_org - v0.xyz();
34 const Vec3vf<M> p1 = ray_org - v1.xyz();
35
36 const vfloat<M> dPdP = sqr(dP);
37 const vfloat<M> dP0 = dot(p0,dP);
38 const vfloat<M> dP1 = dot(p1,dP);
39 const vfloat<M> dOdP = dot(ray_dir,dP);
40
41 // intersect cone body
42 const vfloat<M> dr = v0.w - v1.w;
43 const vfloat<M> hy = dPdP + sqr(dr);
44 const vfloat<M> dO0 = dot(ray_dir,p0);
45 const vfloat<M> OO = sqr(p0);
46 const vfloat<M> dPdP2 = sqr(dPdP);
47 const vfloat<M> dPdPr0 = dPdP*v0.w;
48
49 const vfloat<M> A = dPdP2 - sqr(dOdP)*hy;
50 const vfloat<M> B = dPdP2*dO0 - dP0*dOdP*hy + dPdPr0*(dr*dOdP);
51 const vfloat<M> C = dPdP2*OO - sqr(dP0)*hy + dPdPr0*(2.0f*dr*dP0 - dPdPr0);
52
53 const vfloat<M> D = B*B - A*C;
54 valid &= D >= 0.0f;
55 if (unlikely(none(valid))) {
56 return false;
57 }
58
59 /* standard case for "non-parallel" rays */
60 const vfloat<M> Q = sqrt(D);
61 const vfloat<M> rcp_A = rcp(A);
62 /* special case for rays that are "parallel" to the cone - assume miss */
63 const vbool<M> isParallel = abs(A) <= min_rcp_input;
64
65 vfloat<M> t_cone_lower = select (isParallel, neg_inf, (-B-Q)*rcp_A);
66 vfloat<M> t_cone_upper = select (isParallel, pos_inf, (-B+Q)*rcp_A);
67 const vfloat<M> y_lower = dP0 + t_cone_lower*dOdP;
68 const vfloat<M> y_upper = dP0 + t_cone_upper*dOdP;
69 t_cone_lower = select(valid & y_lower > 0.0f & y_lower < dPdP, t_cone_lower, pos_inf);
70 t_cone_upper = select(valid & y_upper > 0.0f & y_upper < dPdP, t_cone_upper, neg_inf);
71
72 const vbool<M> hitDisk0 = valid & cL;
73 const vbool<M> hitDisk1 = valid & cR;
74 const vfloat<M> rcp_dOdP = rcp(dOdP);
75 const vfloat<M> t_disk0 = select (hitDisk0, select (sqr(p0*dOdP-ray_dir*dP0)<(sqr(v0.w)*sqr(dOdP)), -dP0*rcp_dOdP, pos_inf), pos_inf);
76 const vfloat<M> t_disk1 = select (hitDisk1, select (sqr(p1*dOdP-ray_dir*dP1)<(sqr(v1.w)*sqr(dOdP)), -dP1*rcp_dOdP, pos_inf), pos_inf);
77 const vfloat<M> t_disk_lower = min(t_disk0, t_disk1);
78 const vfloat<M> t_disk_upper = max(t_disk0, t_disk1);
79
80 const vfloat<M> t_lower = min(t_cone_lower, t_disk_lower);
81 const vfloat<M> t_upper = max(t_cone_upper, select(t_lower==t_disk_lower,
82 select(t_disk_upper==vfloat<M>(pos_inf),neg_inf,t_disk_upper),
83 select(t_disk_lower==vfloat<M>(pos_inf),neg_inf,t_disk_lower)));
84
85 const vbool<M> valid_lower = valid & ray_tnear <= dt+t_lower & dt+t_lower <= ray_tfar() & t_lower != vfloat<M>(pos_inf);
86 const vbool<M> valid_upper = valid & ray_tnear <= dt+t_upper & dt+t_upper <= ray_tfar() & t_upper != vfloat<M>(neg_inf);
87
88 const vbool<M> valid_first = valid_lower | valid_upper;
89 if (unlikely(none(valid_first)))
90 return false;
91
92 const vfloat<M> t_first = select(valid_lower, t_lower, t_upper);
93 const vfloat<M> y_first = select(valid_lower, y_lower, y_upper);
94
95 const vfloat<M> rcp_dPdP = rcp(dPdP);
96 const Vec3vf<M> dP2drr0dP = dPdP*dr*v0.w*dP;
97 const Vec3vf<M> dPhy = dP*hy;
98 const vbool<M> cone_hit_first = valid & (t_first == t_cone_lower | t_first == t_cone_upper);
99 const vbool<M> disk0_hit_first = valid & (t_first == t_disk0);
100 const Vec3vf<M> Ng_first = select(cone_hit_first, dPdP2*(p0+t_first*ray_dir)+dP2drr0dP-dPhy*y_first, select(disk0_hit_first, -dP, dP));
101 const vfloat<M> u_first = select(cone_hit_first, y_first*rcp_dPdP, select(disk0_hit_first, vfloat<M>(zero), vfloat<M>(one)));
102
103 /* invoke intersection filter for first hit */
104 RoundLineIntersectorHitM<M> hit(u_first,zero,dt+t_first,Ng_first);
105 const bool is_hit_first = epilog(valid_first, hit);
106
107 /* check for possible second hits before potentially accepted hit */
108 const vfloat<M> t_second = t_upper;
109 const vfloat<M> y_second = y_upper;
110 const vbool<M> valid_second = valid_lower & valid_upper & (dt+t_upper <= ray_tfar());
111 if (unlikely(none(valid_second)))
112 return is_hit_first;
113
114 /* invoke intersection filter for second hit */
115 const vbool<M> cone_hit_second = t_second == t_cone_lower | t_second == t_cone_upper;
116 const vbool<M> disk0_hit_second = t_second == t_disk0;
117 const Vec3vf<M> Ng_second = select(cone_hit_second, dPdP2*(p0+t_second*ray_dir)+dP2drr0dP-dPhy*y_second, select(disk0_hit_second, -dP, dP));
118 const vfloat<M> u_second = select(cone_hit_second, y_second*rcp_dPdP, select(disk0_hit_first, vfloat<M>(zero), vfloat<M>(one)));
119
120 hit = RoundLineIntersectorHitM<M>(u_second,zero,dt+t_second,Ng_second);
121 const bool is_hit_second = epilog(valid_second, hit);
122
123 return is_hit_first | is_hit_second;
124 }
125 }
126
127 template<int M>
128 struct ConeLineIntersectorHitM
129 {
130 __forceinline ConeLineIntersectorHitM() {}
131
132 __forceinline ConeLineIntersectorHitM(const vfloat<M>& u, const vfloat<M>& v, const vfloat<M>& t, const Vec3vf<M>& Ng)
133 : vu(u), vv(v), vt(t), vNg(Ng) {}
134
135 __forceinline void finalize() {}
136
137 __forceinline Vec2f uv (const size_t i) const { return Vec2f(vu[i],vv[i]); }
138 __forceinline float t (const size_t i) const { return vt[i]; }
139 __forceinline Vec3fa Ng(const size_t i) const { return Vec3fa(vNg.x[i],vNg.y[i],vNg.z[i]); }
140
141 public:
142 vfloat<M> vu;
143 vfloat<M> vv;
144 vfloat<M> vt;
145 Vec3vf<M> vNg;
146 };
147
148 template<int M>
149 struct ConeCurveIntersector1
150 {
151 typedef CurvePrecalculations1 Precalculations;
152
153 struct ray_tfar {
154 Ray& ray;
155 __forceinline ray_tfar(Ray& ray) : ray(ray) {}
156 __forceinline vfloat<M> operator() () const { return ray.tfar; };
157 };
158
159 template<typename Epilog>
160 static __forceinline bool intersect(const vbool<M>& valid_i,
161 Ray& ray,
162 IntersectContext* context,
163 const LineSegments* geom,
164 const Precalculations& pre,
165 const Vec4vf<M>& v0i, const Vec4vf<M>& v1i,
166 const vbool<M>& cL, const vbool<M>& cR,
167 const Epilog& epilog)
168 {
169 const Vec3vf<M> ray_org(ray.org.x, ray.org.y, ray.org.z);
170 const Vec3vf<M> ray_dir(ray.dir.x, ray.dir.y, ray.dir.z);
171 const vfloat<M> ray_tnear(ray.tnear());
172 const Vec4vf<M> v0 = enlargeRadiusToMinWidth<M>(context,geom,ray_org,v0i);
173 const Vec4vf<M> v1 = enlargeRadiusToMinWidth<M>(context,geom,ray_org,v1i);
174 return __coneline_internal::intersectCone<M>(valid_i,ray_org,ray_dir,ray_tnear,ray_tfar(ray),v0,v1,cL,cR,epilog);
175 }
176 };
177
178 template<int M, int K>
179 struct ConeCurveIntersectorK
180 {
181 typedef CurvePrecalculationsK<K> Precalculations;
182
183 struct ray_tfar {
184 RayK<K>& ray;
185 size_t k;
186 __forceinline ray_tfar(RayK<K>& ray, size_t k) : ray(ray), k(k) {}
187 __forceinline vfloat<M> operator() () const { return ray.tfar[k]; };
188 };
189
190 template<typename Epilog>
191 static __forceinline bool intersect(const vbool<M>& valid_i,
192 RayK<K>& ray, size_t k,
193 IntersectContext* context,
194 const LineSegments* geom,
195 const Precalculations& pre,
196 const Vec4vf<M>& v0i, const Vec4vf<M>& v1i,
197 const vbool<M>& cL, const vbool<M>& cR,
198 const Epilog& epilog)
199 {
200 const Vec3vf<M> ray_org(ray.org.x[k], ray.org.y[k], ray.org.z[k]);
201 const Vec3vf<M> ray_dir(ray.dir.x[k], ray.dir.y[k], ray.dir.z[k]);
202 const vfloat<M> ray_tnear = ray.tnear()[k];
203 const Vec4vf<M> v0 = enlargeRadiusToMinWidth<M>(context,geom,ray_org,v0i);
204 const Vec4vf<M> v1 = enlargeRadiusToMinWidth<M>(context,geom,ray_org,v1i);
205 return __coneline_internal::intersectCone<M>(valid_i,ray_org,ray_dir,ray_tnear,ray_tfar(ray,k),v0,v1,cL,cR,epilog);
206 }
207 };
208 }
209}
210

source code of qtquick3d/src/3rdparty/embree/kernels/geometry/coneline_intersector.h