1 | /* |
2 | * Copyright (C) 2006, 2007, 2008 Apple Inc. All rights reserved. |
3 | * |
4 | * Redistribution and use in source and binary forms, with or without |
5 | * modification, are permitted provided that the following conditions |
6 | * are met: |
7 | * 1. Redistributions of source code must retain the above copyright |
8 | * notice, this list of conditions and the following disclaimer. |
9 | * 2. Redistributions in binary form must reproduce the above copyright |
10 | * notice, this list of conditions and the following disclaimer in the |
11 | * documentation and/or other materials provided with the distribution. |
12 | * |
13 | * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY |
14 | * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
15 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
16 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR |
17 | * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
18 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
19 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
20 | * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY |
21 | * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
22 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
23 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
24 | */ |
25 | |
26 | #ifndef WTF_MathExtras_h |
27 | #define WTF_MathExtras_h |
28 | |
29 | #include <float.h> |
30 | #include <math.h> |
31 | #include <stdlib.h> |
32 | |
33 | #if OS(SOLARIS) |
34 | #include <ieeefp.h> |
35 | #endif |
36 | |
37 | #if OS(OPENBSD) |
38 | #include <sys/types.h> |
39 | #include <machine/ieee.h> |
40 | #endif |
41 | |
42 | #if COMPILER(MSVC) |
43 | #if OS(WINCE) |
44 | #include <stdlib.h> |
45 | #endif |
46 | #include <limits> |
47 | #endif |
48 | |
49 | #ifndef M_PI |
50 | const double piDouble = 3.14159265358979323846; |
51 | const float piFloat = 3.14159265358979323846f; |
52 | #else |
53 | const double piDouble = M_PI; |
54 | const float piFloat = static_cast<float>(M_PI); |
55 | #endif |
56 | |
57 | #ifndef M_PI_4 |
58 | const double piOverFourDouble = 0.785398163397448309616; |
59 | const float piOverFourFloat = 0.785398163397448309616f; |
60 | #else |
61 | const double piOverFourDouble = M_PI_4; |
62 | const float piOverFourFloat = static_cast<float>(M_PI_4); |
63 | #endif |
64 | |
65 | #if OS(DARWIN) |
66 | |
67 | // Work around a bug in the Mac OS X libc where ceil(-0.1) return +0. |
68 | inline double wtf_ceil(double x) { return copysign(ceil(x), x); } |
69 | |
70 | #define ceil(x) wtf_ceil(x) |
71 | |
72 | #endif |
73 | |
74 | #if OS(SOLARIS) |
75 | |
76 | #ifndef isfinite |
77 | inline bool isfinite(double x) { return finite(x) && !isnand(x); } |
78 | #endif |
79 | #ifndef isinf |
80 | inline bool isinf(double x) { return !finite(x) && !isnand(x); } |
81 | #endif |
82 | #ifndef signbit |
83 | inline bool signbit(double x) { return x < 0.0; } // FIXME: Wrong for negative 0. |
84 | #endif |
85 | |
86 | #endif |
87 | |
88 | #if OS(OPENBSD) |
89 | |
90 | #ifndef isfinite |
91 | inline bool isfinite(double x) { return finite(x); } |
92 | #endif |
93 | #ifndef signbit |
94 | inline bool signbit(double x) { struct ieee_double *p = (struct ieee_double *)&x; return p->dbl_sign; } |
95 | #endif |
96 | |
97 | #endif |
98 | |
99 | #if (COMPILER(MSVC) && _MSC_VER < 1800) || COMPILER(RVCT) |
100 | |
101 | // We must not do 'num + 0.5' or 'num - 0.5' because they can cause precision loss. |
102 | static double round(double num) |
103 | { |
104 | double integer = ceil(num); |
105 | if (num > 0) |
106 | return integer - num > 0.5 ? integer - 1.0 : integer; |
107 | return integer - num >= 0.5 ? integer - 1.0 : integer; |
108 | } |
109 | static float roundf(float num) |
110 | { |
111 | float integer = ceilf(num); |
112 | if (num > 0) |
113 | return integer - num > 0.5f ? integer - 1.0f : integer; |
114 | return integer - num >= 0.5f ? integer - 1.0f : integer; |
115 | } |
116 | inline long long llround(double num) { return static_cast<long long>(round(num)); } |
117 | inline long long llroundf(float num) { return static_cast<long long>(roundf(num)); } |
118 | inline long lround(double num) { return static_cast<long>(round(num)); } |
119 | inline long lroundf(float num) { return static_cast<long>(roundf(num)); } |
120 | inline double trunc(double num) { return num > 0 ? floor(num) : ceil(num); } |
121 | |
122 | #endif |
123 | |
124 | #if COMPILER(MSVC) && _MSC_VER < 1800 |
125 | |
126 | inline bool isinf(double num) { return !_finite(num) && !_isnan(num); } |
127 | inline bool isnan(double num) { return !!_isnan(num); } |
128 | inline bool signbit(double num) { return _copysign(1.0, num) < 0; } |
129 | |
130 | inline double nextafter(double x, double y) { return _nextafter(x, y); } |
131 | inline float nextafterf(float x, float y) { return x > y ? x - FLT_EPSILON : x + FLT_EPSILON; } |
132 | |
133 | inline double copysign(double x, double y) { return _copysign(x, y); } |
134 | inline int isfinite(double x) { return _finite(x); } |
135 | |
136 | // Work around a bug in Win, where atan2(+-infinity, +-infinity) yields NaN instead of specific values. |
137 | inline double wtf_atan2(double x, double y) |
138 | { |
139 | double posInf = std::numeric_limits<double>::infinity(); |
140 | double negInf = -std::numeric_limits<double>::infinity(); |
141 | double nan = std::numeric_limits<double>::quiet_NaN(); |
142 | |
143 | double result = nan; |
144 | |
145 | if (x == posInf && y == posInf) |
146 | result = piOverFourDouble; |
147 | else if (x == posInf && y == negInf) |
148 | result = 3 * piOverFourDouble; |
149 | else if (x == negInf && y == posInf) |
150 | result = -piOverFourDouble; |
151 | else if (x == negInf && y == negInf) |
152 | result = -3 * piOverFourDouble; |
153 | else |
154 | result = ::atan2(x, y); |
155 | |
156 | return result; |
157 | } |
158 | |
159 | // Work around a bug in the Microsoft CRT, where fmod(x, +-infinity) yields NaN instead of x. |
160 | inline double wtf_fmod(double x, double y) { return (!isinf(x) && isinf(y)) ? x : fmod(x, y); } |
161 | |
162 | // Work around a bug in the Microsoft CRT, where pow(NaN, 0) yields NaN instead of 1. |
163 | inline double wtf_pow(double x, double y) { return y == 0 ? 1 : pow(x, y); } |
164 | |
165 | #define atan2(x, y) wtf_atan2(x, y) |
166 | #define fmod(x, y) wtf_fmod(x, y) |
167 | #define pow(x, y) wtf_pow(x, y) |
168 | |
169 | #endif // COMPILER(MSVC) |
170 | |
171 | inline double deg2rad(double d) { return d * piDouble / 180.0; } |
172 | inline double rad2deg(double r) { return r * 180.0 / piDouble; } |
173 | inline double deg2grad(double d) { return d * 400.0 / 360.0; } |
174 | inline double grad2deg(double g) { return g * 360.0 / 400.0; } |
175 | inline double turn2deg(double t) { return t * 360.0; } |
176 | inline double deg2turn(double d) { return d / 360.0; } |
177 | inline double rad2grad(double r) { return r * 200.0 / piDouble; } |
178 | inline double grad2rad(double g) { return g * piDouble / 200.0; } |
179 | |
180 | inline float deg2rad(float d) { return d * piFloat / 180.0f; } |
181 | inline float rad2deg(float r) { return r * 180.0f / piFloat; } |
182 | inline float deg2grad(float d) { return d * 400.0f / 360.0f; } |
183 | inline float grad2deg(float g) { return g * 360.0f / 400.0f; } |
184 | inline float turn2deg(float t) { return t * 360.0f; } |
185 | inline float deg2turn(float d) { return d / 360.0f; } |
186 | inline float rad2grad(float r) { return r * 200.0f / piFloat; } |
187 | inline float grad2rad(float g) { return g * piFloat / 200.0f; } |
188 | |
189 | #endif // #ifndef WTF_MathExtras_h |
190 | |