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 "../common/scene_points.h"
8#include "curve_intersector_precalculations.h"
9
10namespace embree
11{
12 namespace isa
13 {
14 template<int M>
15 struct SphereIntersectorHitM
16 {
17 __forceinline SphereIntersectorHitM() {}
18
19 __forceinline SphereIntersectorHitM(const vfloat<M>& t, const Vec3vf<M>& Ng)
20 : vt(t), vNg(Ng) {}
21
22 __forceinline void finalize() {}
23
24 __forceinline Vec2f uv(const size_t i) const {
25 return Vec2f(0.0f, 0.0f);
26 }
27 __forceinline float t(const size_t i) const {
28 return vt[i];
29 }
30 __forceinline Vec3fa Ng(const size_t i) const {
31 return Vec3fa(vNg.x[i], vNg.y[i], vNg.z[i]);
32 }
33
34 public:
35 vfloat<M> vt;
36 Vec3vf<M> vNg;
37 };
38
39 template<int M>
40 struct SphereIntersector1
41 {
42 typedef CurvePrecalculations1 Precalculations;
43
44 template<typename Epilog>
45 static __forceinline bool intersect(
46 const vbool<M>& valid_i, Ray& ray,
47 const Precalculations& pre, const Vec4vf<M>& v0, const Epilog& epilog)
48 {
49 vbool<M> valid = valid_i;
50
51 const vfloat<M> rd2 = rcp(x: dot(a: ray.dir, b: ray.dir));
52 const Vec3vf<M> ray_org(ray.org.x, ray.org.y, ray.org.z);
53 const Vec3vf<M> ray_dir(ray.dir.x, ray.dir.y, ray.dir.z);
54 const Vec3vf<M> center = v0.xyz();
55 const vfloat<M> radius = v0.w;
56
57 const Vec3vf<M> c0 = center - ray_org;
58 const vfloat<M> projC0 = dot(c0, ray_dir) * rd2;
59 const Vec3vf<M> perp = c0 - projC0 * ray_dir;
60 const vfloat<M> l2 = dot(perp, perp);
61 const vfloat<M> r2 = radius * radius;
62 valid &= (l2 <= r2);
63 if (unlikely(none(valid)))
64 return false;
65
66 const vfloat<M> td = sqrt((r2 - l2) * rd2);
67 const vfloat<M> t_front = projC0 - td;
68 const vfloat<M> t_back = projC0 + td;
69
70 const vbool<M> valid_front = valid & (ray.tnear() <= t_front) & (t_front <= ray.tfar);
71 const vbool<M> valid_back = valid & (ray.tnear() <= t_back ) & (t_back <= ray.tfar);
72
73 /* check if there is a first hit */
74 const vbool<M> valid_first = valid_front | valid_back;
75 if (unlikely(none(valid_first)))
76 return false;
77
78 /* construct first hit */
79 const vfloat<M> td_front = -td;
80 const vfloat<M> td_back = +td;
81 const vfloat<M> t_first = select(valid_front, t_front, t_back);
82 const Vec3vf<M> Ng_first = select(valid_front, td_front, td_back) * ray_dir - perp;
83 SphereIntersectorHitM<M> hit(t_first, Ng_first);
84
85 /* invoke intersection filter for first hit */
86 const bool is_hit_first = epilog(valid_first, hit);
87
88 /* check for possible second hits before potentially accepted hit */
89 const vfloat<M> t_second = t_back;
90 const vbool<M> valid_second = valid_front & valid_back & (t_second <= ray.tfar);
91 if (unlikely(none(valid_second)))
92 return is_hit_first;
93
94 /* invoke intersection filter for second hit */
95 const Vec3vf<M> Ng_second = td_back * ray_dir - perp;
96 hit = SphereIntersectorHitM<M> (t_second, Ng_second);
97 const bool is_hit_second = epilog(valid_second, hit);
98
99 return is_hit_first | is_hit_second;
100 }
101
102 template<typename Epilog>
103 static __forceinline bool intersect(
104 const vbool<M>& valid_i, Ray& ray, IntersectContext* context, const Points* geom,
105 const Precalculations& pre, const Vec4vf<M>& v0i, const Epilog& epilog)
106 {
107 const Vec3vf<M> ray_org(ray.org.x, ray.org.y, ray.org.z);
108 const Vec4vf<M> v0 = enlargeRadiusToMinWidth<M>(context,geom,ray_org,v0i);
109 return intersect(valid_i,ray,pre,v0,epilog);
110 }
111 };
112
113 template<int M, int K>
114 struct SphereIntersectorK
115 {
116 typedef CurvePrecalculationsK<K> Precalculations;
117
118 template<typename Epilog>
119 static __forceinline bool intersect(const vbool<M>& valid_i,
120 RayK<K>& ray, size_t k,
121 IntersectContext* context,
122 const Points* geom,
123 const Precalculations& pre,
124 const Vec4vf<M>& v0i,
125 const Epilog& epilog)
126 {
127 vbool<M> valid = valid_i;
128
129 const Vec3vf<M> ray_org(ray.org.x[k], ray.org.y[k], ray.org.z[k]);
130 const Vec3vf<M> ray_dir(ray.dir.x[k], ray.dir.y[k], ray.dir.z[k]);
131 const vfloat<M> rd2 = rcp(dot(ray_dir, ray_dir));
132
133 const Vec4vf<M> v0 = enlargeRadiusToMinWidth<M>(context,geom,ray_org,v0i);
134 const Vec3vf<M> center = v0.xyz();
135 const vfloat<M> radius = v0.w;
136
137 const Vec3vf<M> c0 = center - ray_org;
138 const vfloat<M> projC0 = dot(c0, ray_dir) * rd2;
139 const Vec3vf<M> perp = c0 - projC0 * ray_dir;
140 const vfloat<M> l2 = dot(perp, perp);
141 const vfloat<M> r2 = radius * radius;
142 valid &= (l2 <= r2);
143 if (unlikely(none(valid)))
144 return false;
145
146 const vfloat<M> td = sqrt((r2 - l2) * rd2);
147 const vfloat<M> t_front = projC0 - td;
148 const vfloat<M> t_back = projC0 + td;
149
150 const vbool<M> valid_front = valid & (ray.tnear()[k] <= t_front) & (t_front <= ray.tfar[k]);
151 const vbool<M> valid_back = valid & (ray.tnear()[k] <= t_back ) & (t_back <= ray.tfar[k]);
152
153 /* check if there is a first hit */
154 const vbool<M> valid_first = valid_front | valid_back;
155 if (unlikely(none(valid_first)))
156 return false;
157
158 /* construct first hit */
159 const vfloat<M> td_front = -td;
160 const vfloat<M> td_back = +td;
161 const vfloat<M> t_first = select(valid_front, t_front, t_back);
162 const Vec3vf<M> Ng_first = select(valid_front, td_front, td_back) * ray_dir - perp;
163 SphereIntersectorHitM<M> hit(t_first, Ng_first);
164
165 /* invoke intersection filter for first hit */
166 const bool is_hit_first = epilog(valid_first, hit);
167
168 /* check for possible second hits before potentially accepted hit */
169 const vfloat<M> t_second = t_back;
170 const vbool<M> valid_second = valid_front & valid_back & (t_second <= ray.tfar[k]);
171 if (unlikely(none(valid_second)))
172 return is_hit_first;
173
174 /* invoke intersection filter for second hit */
175 const Vec3vf<M> Ng_second = td_back * ray_dir - perp;
176 hit = SphereIntersectorHitM<M> (t_second, Ng_second);
177 const bool is_hit_second = epilog(valid_second, hit);
178
179 return is_hit_first | is_hit_second;
180 }
181 };
182 } // namespace isa
183} // namespace embree
184

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