1 | // Copyright 2009-2021 Intel Corporation |
2 | // SPDX-License-Identifier: Apache-2.0 |
3 | |
4 | #pragma once |
5 | |
6 | #include "vec2.h" |
7 | #include "vec3.h" |
8 | #include "bbox.h" |
9 | |
10 | namespace embree |
11 | { |
12 | template<typename V> |
13 | struct Interval |
14 | { |
15 | V lower, upper; |
16 | |
17 | __forceinline Interval() {} |
18 | __forceinline Interval ( const Interval& other ) { lower = other.lower; upper = other.upper; } |
19 | __forceinline Interval& operator=( const Interval& other ) { lower = other.lower; upper = other.upper; return *this; } |
20 | |
21 | __forceinline Interval(const V& a) : lower(a), upper(a) {} |
22 | __forceinline Interval(const V& lower, const V& upper) : lower(lower), upper(upper) {} |
23 | __forceinline Interval(const BBox<V>& a) : lower(a.lower), upper(a.upper) {} |
24 | |
25 | /*! tests if box is empty */ |
26 | //__forceinline bool empty() const { return lower > upper; } |
27 | |
28 | /*! computes the size of the interval */ |
29 | __forceinline V size() const { return upper - lower; } |
30 | |
31 | __forceinline V center() const { return 0.5f*(lower+upper); } |
32 | |
33 | __forceinline const Interval& extend(const Interval& other) { lower = min(lower,other.lower); upper = max(upper,other.upper); return *this; } |
34 | __forceinline const Interval& extend(const V & other) { lower = min(lower,other ); upper = max(upper,other ); return *this; } |
35 | |
36 | __forceinline friend Interval operator +( const Interval& a, const Interval& b ) { |
37 | return Interval(a.lower+b.lower,a.upper+b.upper); |
38 | } |
39 | |
40 | __forceinline friend Interval operator -( const Interval& a, const Interval& b ) { |
41 | return Interval(a.lower-b.upper,a.upper-b.lower); |
42 | } |
43 | |
44 | __forceinline friend Interval operator -( const Interval& a, const V& b ) { |
45 | return Interval(a.lower-b,a.upper-b); |
46 | } |
47 | |
48 | __forceinline friend Interval operator *( const Interval& a, const Interval& b ) |
49 | { |
50 | const V ll = a.lower*b.lower; |
51 | const V lu = a.lower*b.upper; |
52 | const V ul = a.upper*b.lower; |
53 | const V uu = a.upper*b.upper; |
54 | return Interval(min(ll,lu,ul,uu),max(ll,lu,ul,uu)); |
55 | } |
56 | |
57 | __forceinline friend Interval merge( const Interval& a, const Interval& b) { |
58 | return Interval(min(a.lower,b.lower),max(a.upper,b.upper)); |
59 | } |
60 | |
61 | __forceinline friend Interval merge( const Interval& a, const Interval& b, const Interval& c) { |
62 | return merge(merge(a,b),c); |
63 | } |
64 | |
65 | __forceinline friend Interval merge( const Interval& a, const Interval& b, const Interval& c, const Interval& d) { |
66 | return merge(merge(a,b),merge(c,d)); |
67 | } |
68 | |
69 | /*! intersect bounding boxes */ |
70 | __forceinline friend const Interval intersect( const Interval& a, const Interval& b ) { return Interval(max(a.lower, b.lower), min(a.upper, b.upper)); } |
71 | __forceinline friend const Interval intersect( const Interval& a, const Interval& b, const Interval& c ) { return intersect(a,intersect(b,c)); } |
72 | __forceinline friend const Interval intersect( const Interval& a, const Interval& b, const Interval& c, const Interval& d ) { return intersect(intersect(a,b),intersect(c,d)); } |
73 | |
74 | friend embree_ostream operator<<(embree_ostream cout, const Interval& a) { |
75 | return cout << "[" << a.lower << ", " << a.upper << "]" ; |
76 | } |
77 | |
78 | //////////////////////////////////////////////////////////////////////////////// |
79 | /// Constants |
80 | //////////////////////////////////////////////////////////////////////////////// |
81 | |
82 | __forceinline Interval( EmptyTy ) : lower(pos_inf), upper(neg_inf) {} |
83 | __forceinline Interval( FullTy ) : lower(neg_inf), upper(pos_inf) {} |
84 | }; |
85 | |
86 | __forceinline bool isEmpty(const Interval<float>& v) { |
87 | return v.lower > v.upper; |
88 | } |
89 | |
90 | __forceinline vboolx isEmpty(const Interval<vfloatx>& v) { |
91 | return v.lower > v.upper; |
92 | } |
93 | |
94 | /*! subset relation */ |
95 | template<typename T> __forceinline bool subset( const Interval<T>& a, const Interval<T>& b ) { |
96 | return (a.lower > b.lower) && (a.upper < b.upper); |
97 | } |
98 | |
99 | template<typename T> __forceinline bool subset( const Vec2<Interval<T>>& a, const Vec2<Interval<T>>& b ) { |
100 | return subset(a.x,b.x) && subset(a.y,b.y); |
101 | } |
102 | |
103 | template<typename T> __forceinline const Vec2<Interval<T>> intersect( const Vec2<Interval<T>>& a, const Vec2<Interval<T>>& b ) { |
104 | return Vec2<Interval<T>>(intersect(a.x,b.x),intersect(a.y,b.y)); |
105 | } |
106 | |
107 | //////////////////////////////////////////////////////////////////////////////// |
108 | /// Select |
109 | //////////////////////////////////////////////////////////////////////////////// |
110 | |
111 | template<typename T> __forceinline Interval<T> select ( bool s, const Interval<T>& t, const Interval<T>& f ) { |
112 | return Interval<T>(select(s,t.lower,f.lower),select(s,t.upper,f.upper)); |
113 | } |
114 | |
115 | template<typename T> __forceinline Interval<T> select ( const typename T::Bool& s, const Interval<T>& t, const Interval<T>& f ) { |
116 | return Interval<T>(select(s,t.lower,f.lower),select(s,t.upper,f.upper)); |
117 | } |
118 | |
119 | __forceinline int numRoots(const Interval<float>& p0, const Interval<float>& p1) |
120 | { |
121 | float eps = 1E-4f; |
122 | bool neg0 = p0.lower < eps; bool pos0 = p0.upper > -eps; |
123 | bool neg1 = p1.lower < eps; bool pos1 = p1.upper > -eps; |
124 | return (neg0 && pos1) || (pos0 && neg1) || (neg0 && pos0) || (neg1 && pos1); |
125 | } |
126 | |
127 | typedef Interval<float> Interval1f; |
128 | typedef Vec2<Interval<float>> Interval2f; |
129 | typedef Vec3<Interval<float>> Interval3f; |
130 | |
131 | inline void swap(float& a, float& b) { float tmp = a; a = b; b = tmp; } |
132 | |
133 | inline Interval1f shift(const Interval1f& v, float shift) { return Interval1f(v.lower + shift, v.upper + shift); } |
134 | |
135 | #define TWO_PI (2.0*M_PI) |
136 | inline Interval1f sin(Interval1f interval) |
137 | { |
138 | if (interval.upper-interval.lower >= M_PI) { return Interval1f(-1.0, 1.0); } |
139 | if (interval.upper > TWO_PI) { interval = shift(v: interval, shift: -TWO_PI*floor(x: interval.upper/TWO_PI)); } |
140 | if (interval.lower < 0) { interval = shift(v: interval, shift: -TWO_PI*floor(x: interval.lower/TWO_PI)); } |
141 | float sinLower = sin(x: interval.lower); |
142 | float sinUpper = sin(x: interval.upper); |
143 | if (sinLower > sinUpper) swap(a&: sinLower, b&: sinUpper); |
144 | if (interval.lower < M_PI / 2.0 && interval.upper > M_PI / 2.0) sinUpper = 1.0; |
145 | if (interval.lower < 3.0 * M_PI / 2.0 && interval.upper > 3.0 * M_PI / 2.0) sinLower = -1.0; |
146 | return Interval1f(sinLower, sinUpper); |
147 | } |
148 | |
149 | inline Interval1f cos(Interval1f interval) |
150 | { |
151 | if (interval.upper-interval.lower >= M_PI) { return Interval1f(-1.0, 1.0); } |
152 | if (interval.upper > TWO_PI) { interval = shift(v: interval, shift: -TWO_PI*floor(x: interval.upper/TWO_PI)); } |
153 | if (interval.lower < 0) { interval = shift(v: interval, shift: -TWO_PI*floor(x: interval.lower/TWO_PI)); } |
154 | float cosLower = cos(x: interval.lower); |
155 | float cosUpper = cos(x: interval.upper); |
156 | if (cosLower > cosUpper) swap(a&: cosLower, b&: cosUpper); |
157 | if (interval.lower < M_PI && interval.upper > M_PI) cosLower = -1.0; |
158 | return Interval1f(cosLower, cosUpper); |
159 | } |
160 | #undef TWO_PI |
161 | } |
162 | |