1// Copyright 2009-2021 Intel Corporation
2// SPDX-License-Identifier: Apache-2.0
3
4#pragma once
5
6#include "../common/ray.h"
7
8namespace embree
9{
10 namespace isa
11 {
12 struct Cylinder
13 {
14 const Vec3fa p0; //!< start location
15 const Vec3fa p1; //!< end position
16 const float rr; //!< squared radius of cylinder
17
18 __forceinline Cylinder(const Vec3fa& p0, const Vec3fa& p1, const float r)
19 : p0(p0), p1(p1), rr(sqr(r)) {}
20
21 __forceinline Cylinder(const Vec3fa& p0, const Vec3fa& p1, const float rr, bool)
22 : p0(p0), p1(p1), rr(rr) {}
23
24 __forceinline bool intersect(const Vec3fa& org,
25 const Vec3fa& dir,
26 BBox1f& t_o,
27 float& u0_o, Vec3fa& Ng0_o,
28 float& u1_o, Vec3fa& Ng1_o) const
29 {
30 /* calculate quadratic equation to solve */
31 const float rl = rcp_length(p1-p0);
32 const Vec3fa P0 = p0, dP = (p1-p0)*rl;
33 const Vec3fa O = org-P0, dO = dir;
34
35 const float dOdO = dot(dO,dO);
36 const float OdO = dot(dO,O);
37 const float OO = dot(O,O);
38 const float dOz = dot(dP,dO);
39 const float Oz = dot(dP,O);
40
41 const float A = dOdO - sqr(dOz);
42 const float B = 2.0f * (OdO - dOz*Oz);
43 const float C = OO - sqr(Oz) - rr;
44
45 /* we miss the cylinder if determinant is smaller than zero */
46 const float D = B*B - 4.0f*A*C;
47 if (D < 0.0f) {
48 t_o = BBox1f(pos_inf,neg_inf);
49 return false;
50 }
51
52 /* special case for rays that are parallel to the cylinder */
53 const float eps = 16.0f*float(ulp)*max(abs(dOdO),abs(sqr(dOz)));
54 if (abs(A) < eps)
55 {
56 if (C <= 0.0f) {
57 t_o = BBox1f(neg_inf,pos_inf);
58 return true;
59 } else {
60 t_o = BBox1f(pos_inf,neg_inf);
61 return false;
62 }
63 }
64
65 /* standard case for rays that are not parallel to the cylinder */
66 const float Q = sqrt(D);
67 const float rcp_2A = rcp(2.0f*A);
68 const float t0 = (-B-Q)*rcp_2A;
69 const float t1 = (-B+Q)*rcp_2A;
70
71 /* calculates u and Ng for near hit */
72 {
73 u0_o = madd(t0,dOz,Oz)*rl;
74 const Vec3fa Pr = t0*dir;
75 const Vec3fa Pl = madd(u0_o,p1-p0,p0);
76 Ng0_o = Pr-Pl;
77 }
78
79 /* calculates u and Ng for far hit */
80 {
81 u1_o = madd(t1,dOz,Oz)*rl;
82 const Vec3fa Pr = t1*dir;
83 const Vec3fa Pl = madd(u1_o,p1-p0,p0);
84 Ng1_o = Pr-Pl;
85 }
86
87 t_o.lower = t0;
88 t_o.upper = t1;
89 return true;
90 }
91
92 __forceinline bool intersect(const Vec3fa& org_i, const Vec3fa& dir, BBox1f& t_o) const
93 {
94 float u0_o; Vec3fa Ng0_o;
95 float u1_o; Vec3fa Ng1_o;
96 return intersect(org_i,dir,t_o,u0_o,Ng0_o,u1_o,Ng1_o);
97 }
98
99 static bool verify(const size_t id, const Cylinder& cylinder, const RayHit& ray, bool shouldhit, const float t0, const float t1)
100 {
101 float eps = 0.001f;
102 BBox1f t; bool hit;
103 hit = cylinder.intersect(ray.org,ray.dir,t);
104
105 bool failed = hit != shouldhit;
106 if (shouldhit) failed |= std::isinf(t0) ? t0 != t.lower : abs(t0-t.lower) > eps;
107 if (shouldhit) failed |= std::isinf(t1) ? t1 != t.upper : abs(t1-t.upper) > eps;
108 if (!failed) return true;
109 embree_cout << "Cylinder test " << id << " failed: cylinder = " << cylinder << ", ray = " << ray << ", hit = " << hit << ", t = " << t << embree_endl;
110 return false;
111 }
112
113 /* verify cylinder class */
114 static bool verify()
115 {
116 bool passed = true;
117 const Cylinder cylinder(Vec3fa(0.0f,0.0f,0.0f),Vec3fa(1.0f,0.0f,0.0f),1.0f);
118 passed &= verify(0,cylinder,RayHit(Vec3fa(-2.0f,1.0f,0.0f),Vec3fa( 0.0f,-1.0f,+0.0f),0.0f,float(inf)),true,0.0f,2.0f);
119 passed &= verify(1,cylinder,RayHit(Vec3fa(+2.0f,1.0f,0.0f),Vec3fa( 0.0f,-1.0f,+0.0f),0.0f,float(inf)),true,0.0f,2.0f);
120 passed &= verify(2,cylinder,RayHit(Vec3fa(+2.0f,1.0f,2.0f),Vec3fa( 0.0f,-1.0f,+0.0f),0.0f,float(inf)),false,0.0f,0.0f);
121 passed &= verify(3,cylinder,RayHit(Vec3fa(+0.0f,0.0f,0.0f),Vec3fa( 1.0f, 0.0f,+0.0f),0.0f,float(inf)),true,neg_inf,pos_inf);
122 passed &= verify(4,cylinder,RayHit(Vec3fa(+0.0f,0.0f,0.0f),Vec3fa(-1.0f, 0.0f,+0.0f),0.0f,float(inf)),true,neg_inf,pos_inf);
123 passed &= verify(5,cylinder,RayHit(Vec3fa(+0.0f,2.0f,0.0f),Vec3fa( 1.0f, 0.0f,+0.0f),0.0f,float(inf)),false,pos_inf,neg_inf);
124 passed &= verify(6,cylinder,RayHit(Vec3fa(+0.0f,2.0f,0.0f),Vec3fa(-1.0f, 0.0f,+0.0f),0.0f,float(inf)),false,pos_inf,neg_inf);
125 return passed;
126 }
127
128 /*! output operator */
129 friend __forceinline embree_ostream operator<<(embree_ostream cout, const Cylinder& c) {
130 return cout << "Cylinder { p0 = " << c.p0 << ", p1 = " << c.p1 << ", r = " << sqrtf(c.rr) << "}";
131 }
132 };
133
134 template<int N>
135 struct CylinderN
136 {
137 const Vec3vf<N> p0; //!< start location
138 const Vec3vf<N> p1; //!< end position
139 const vfloat<N> rr; //!< squared radius of cylinder
140
141 __forceinline CylinderN(const Vec3vf<N>& p0, const Vec3vf<N>& p1, const vfloat<N>& r)
142 : p0(p0), p1(p1), rr(sqr(r)) {}
143
144 __forceinline CylinderN(const Vec3vf<N>& p0, const Vec3vf<N>& p1, const vfloat<N>& rr, bool)
145 : p0(p0), p1(p1), rr(rr) {}
146
147
148 __forceinline vbool<N> intersect(const Vec3fa& org, const Vec3fa& dir,
149 BBox<vfloat<N>>& t_o,
150 vfloat<N>& u0_o, Vec3vf<N>& Ng0_o,
151 vfloat<N>& u1_o, Vec3vf<N>& Ng1_o) const
152 {
153 /* calculate quadratic equation to solve */
154 const vfloat<N> rl = rcp_length(p1-p0);
155 const Vec3vf<N> P0 = p0, dP = (p1-p0)*rl;
156 const Vec3vf<N> O = Vec3vf<N>(org)-P0, dO = dir;
157
158 const vfloat<N> dOdO = dot(dO,dO);
159 const vfloat<N> OdO = dot(dO,O);
160 const vfloat<N> OO = dot(O,O);
161 const vfloat<N> dOz = dot(dP,dO);
162 const vfloat<N> Oz = dot(dP,O);
163
164 const vfloat<N> A = dOdO - sqr(dOz);
165 const vfloat<N> B = 2.0f * (OdO - dOz*Oz);
166 const vfloat<N> C = OO - sqr(Oz) - rr;
167
168 /* we miss the cylinder if determinant is smaller than zero */
169 const vfloat<N> D = B*B - 4.0f*A*C;
170 vbool<N> valid = D >= 0.0f;
171 if (none(valid)) {
172 t_o = BBox<vfloat<N>>(empty);
173 return valid;
174 }
175
176 /* standard case for rays that are not parallel to the cylinder */
177 const vfloat<N> Q = sqrt(D);
178 const vfloat<N> rcp_2A = rcp(2.0f*A);
179 const vfloat<N> t0 = (-B-Q)*rcp_2A;
180 const vfloat<N> t1 = (-B+Q)*rcp_2A;
181
182 /* calculates u and Ng for near hit */
183 {
184 u0_o = madd(t0,dOz,Oz)*rl;
185 const Vec3vf<N> Pr = t0*Vec3vf<N>(dir);
186 const Vec3vf<N> Pl = madd(u0_o,p1-p0,p0);
187 Ng0_o = Pr-Pl;
188 }
189
190 /* calculates u and Ng for far hit */
191 {
192 u1_o = madd(t1,dOz,Oz)*rl;
193 const Vec3vf<N> Pr = t1*Vec3vf<N>(dir);
194 const Vec3vf<N> Pl = madd(u1_o,p1-p0,p0);
195 Ng1_o = Pr-Pl;
196 }
197
198 t_o.lower = select(valid, t0, vfloat<N>(pos_inf));
199 t_o.upper = select(valid, t1, vfloat<N>(neg_inf));
200
201 /* special case for rays that are parallel to the cylinder */
202 const vfloat<N> eps = 16.0f*float(ulp)*max(abs(dOdO),abs(sqr(dOz)));
203 vbool<N> validt = valid & (abs(A) < eps);
204 if (unlikely(any(validt)))
205 {
206 vbool<N> inside = C <= 0.0f;
207 t_o.lower = select(validt,select(inside,vfloat<N>(neg_inf),vfloat<N>(pos_inf)),t_o.lower);
208 t_o.upper = select(validt,select(inside,vfloat<N>(pos_inf),vfloat<N>(neg_inf)),t_o.upper);
209 valid &= !validt | inside;
210 }
211 return valid;
212 }
213
214 __forceinline vbool<N> intersect(const Vec3fa& org_i, const Vec3fa& dir, BBox<vfloat<N>>& t_o) const
215 {
216 vfloat<N> u0_o; Vec3vf<N> Ng0_o;
217 vfloat<N> u1_o; Vec3vf<N> Ng1_o;
218 return intersect(org_i,dir,t_o,u0_o,Ng0_o,u1_o,Ng1_o);
219 }
220 };
221 }
222}
223
224