1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
|
/// @ref gtx_fast_trigonometry
/// @file glm/gtx/fast_trigonometry.inl
namespace glm{
namespace detail
{
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> taylorCos(vec<L, T, Q> const& x)
{
return static_cast<T>(1)
- (x * x) * (1.f / 2.f)
+ ((x * x) * (x * x)) * (1.f / 24.f)
- (((x * x) * (x * x)) * (x * x)) * (1.f / 720.f)
+ (((x * x) * (x * x)) * ((x * x) * (x * x))) * (1.f / 40320.f);
}
template<typename T>
GLM_FUNC_QUALIFIER T cos_52s(T x)
{
T const xx(x * x);
return (T(0.9999932946) + xx * (T(-0.4999124376) + xx * (T(0.0414877472) + xx * T(-0.0012712095))));
}
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> cos_52s(vec<L, T, Q> const& x)
{
return detail::functor1<L, T, T, Q>::call(cos_52s, x);
}
}//namespace detail
// wrapAngle
template<typename T>
GLM_FUNC_QUALIFIER T wrapAngle(T angle)
{
return abs<T>(mod<T>(angle, two_pi<T>()));
}
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> wrapAngle(vec<L, T, Q> const& x)
{
return detail::functor1<L, T, T, Q>::call(wrapAngle, x);
}
// cos
template<typename T>
GLM_FUNC_QUALIFIER T fastCos(T x)
{
T const angle(wrapAngle<T>(x));
if(angle < half_pi<T>())
return detail::cos_52s(angle);
if(angle < pi<T>())
return -detail::cos_52s(pi<T>() - angle);
if(angle < (T(3) * half_pi<T>()))
return -detail::cos_52s(angle - pi<T>());
return detail::cos_52s(two_pi<T>() - angle);
}
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> fastCos(vec<L, T, Q> const& x)
{
return detail::functor1<L, T, T, Q>::call(fastCos, x);
}
// sin
template<typename T>
GLM_FUNC_QUALIFIER T fastSin(T x)
{
return fastCos<T>(half_pi<T>() - x);
}
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> fastSin(vec<L, T, Q> const& x)
{
return detail::functor1<L, T, T, Q>::call(fastSin, x);
}
// tan
template<typename T>
GLM_FUNC_QUALIFIER T fastTan(T x)
{
return x + (x * x * x * T(0.3333333333)) + (x * x * x * x * x * T(0.1333333333333)) + (x * x * x * x * x * x * x * T(0.0539682539));
}
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> fastTan(vec<L, T, Q> const& x)
{
return detail::functor1<L, T, T, Q>::call(fastTan, x);
}
// asin
template<typename T>
GLM_FUNC_QUALIFIER T fastAsin(T x)
{
return x + (x * x * x * T(0.166666667)) + (x * x * x * x * x * T(0.075)) + (x * x * x * x * x * x * x * T(0.0446428571)) + (x * x * x * x * x * x * x * x * x * T(0.0303819444));// + (x * x * x * x * x * x * x * x * x * x * x * T(0.022372159));
}
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> fastAsin(vec<L, T, Q> const& x)
{
return detail::functor1<L, T, T, Q>::call(fastAsin, x);
}
// acos
template<typename T>
GLM_FUNC_QUALIFIER T fastAcos(T x)
{
return T(1.5707963267948966192313216916398) - fastAsin(x); //(PI / 2)
}
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> fastAcos(vec<L, T, Q> const& x)
{
return detail::functor1<L, T, T, Q>::call(fastAcos, x);
}
// atan
template<typename T>
GLM_FUNC_QUALIFIER T fastAtan(T y, T x)
{
T sgn = sign(y) * sign(x);
return abs(fastAtan(y / x)) * sgn;
}
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> fastAtan(vec<L, T, Q> const& y, vec<L, T, Q> const& x)
{
return detail::functor2<L, T, Q>::call(fastAtan, y, x);
}
template<typename T>
GLM_FUNC_QUALIFIER T fastAtan(T x)
{
return x - (x * x * x * T(0.333333333333)) + (x * x * x * x * x * T(0.2)) - (x * x * x * x * x * x * x * T(0.1428571429)) + (x * x * x * x * x * x * x * x * x * T(0.111111111111)) - (x * x * x * x * x * x * x * x * x * x * x * T(0.0909090909));
}
template<length_t L, typename T, qualifier Q>
GLM_FUNC_QUALIFIER vec<L, T, Q> fastAtan(vec<L, T, Q> const& x)
{
return detail::functor1<L, T, T, Q>::call(fastAtan, x);
}
}//namespace glm
|