| 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 |  |