1 /////////////////////////////////////////////////////////////////////////////////////////////////// 2 // OpenGL Mathematics Copyright (c) 2005 - 2014 G-Truc Creation (www.g-truc.net) 3 /////////////////////////////////////////////////////////////////////////////////////////////////// 4 // Created : 2006-01-08 5 // Updated : 2011-10-14 6 // Licence : This source is under MIT License 7 // File : glm/gtx/fast_trigonometry.inl 8 /////////////////////////////////////////////////////////////////////////////////////////////////// 9 10 namespace glm 11 { 12 // sin 13 template <typename T> 14 GLM_FUNC_QUALIFIER T fastSin(T const & x) 15 { 16 return x - ((x * x * x) / T(6)) + ((x * x * x * x * x) / T(120)) - ((x * x * x * x * x * x * x) / T(5040)); 17 } 18 19 VECTORIZE_VEC(fastSin) 20 21 // cos 22 template <typename T> 23 GLM_FUNC_QUALIFIER T fastCos(T const & x) 24 { 25 return T(1) - (x * x * T(0.5)) + (x * x * x * x * T(0.041666666666)) - (x * x * x * x * x * x * T(0.00138888888888)); 26 } 27 28 VECTORIZE_VEC(fastCos) 29 30 // tan 31 template <typename T> 32 GLM_FUNC_QUALIFIER T fastTan(T const & x) 33 { 34 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)); 35 } 36 37 VECTORIZE_VEC(fastTan) 38 39 // asin 40 template <typename T> 41 GLM_FUNC_QUALIFIER T fastAsin(T const & x) 42 { 43 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)); 44 } 45 46 VECTORIZE_VEC(fastAsin) 47 48 // acos 49 template <typename T> 50 GLM_FUNC_QUALIFIER T fastAcos(T const & x) 51 { 52 return T(1.5707963267948966192313216916398) - fastAsin(x); //(PI / 2) 53 } 54 55 VECTORIZE_VEC(fastAcos) 56 57 // atan 58 template <typename T> 59 GLM_FUNC_QUALIFIER T fastAtan(T const & y, T const & x) 60 { 61 T sgn = sign(y) * sign(x); 62 return abs(fastAtan(y / x)) * sgn; 63 } 64 65 VECTORIZE_VEC_VEC(fastAtan) 66 67 template <typename T> 68 GLM_FUNC_QUALIFIER T fastAtan(T const & x) 69 { 70 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)); 71 } 72 73 VECTORIZE_VEC(fastAtan) 74 75 }//namespace glm 76
