1 /*
2  * Carla math utils
3  * Copyright (C) 2011-2021 Filipe Coelho <falktx@falktx.com>
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License as
7  * published by the Free Software Foundation; either version 2 of
8  * the License, or any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13  * GNU General Public License for more details.
14  *
15  * For a full copy of the GNU General Public License see the doc/GPL.txt file.
16  */
17 
18 #ifndef CARLA_MATH_UTILS_HPP_INCLUDED
19 #define CARLA_MATH_UTILS_HPP_INCLUDED
20 
21 #include "CarlaUtils.hpp"
22 
23 #include <cmath>
24 #include <limits>
25 
26 // --------------------------------------------------------------------------------------------------------------------
27 // math functions (base)
28 
29 /*
30  * Return the lower of 2 values, with 'min' as the minimum possible value (ie, constrain).
31  */
32 template<typename T>
33 static inline
carla_minConstrained(const T & v1,const T & v2,const T & min)34 const T& carla_minConstrained(const T& v1, const T& v2, const T& min) noexcept
35 {
36     return (v1 <= min || v2 <= min) ? min : (v1 < v2 ? v1 : v2);
37 }
38 
39 /*
40  * Return the lower positive of 2 values.
41  * If one of the values is zero, returns zero.
42  * If one value is negative but the other positive, returns the positive.
43  * Returned value is guaranteed to be >= 0.
44  */
45 template<typename T>
46 static inline
carla_minPositive(const T & v1,const T & v2)47 T carla_minPositive(const T& v1, const T& v2) noexcept
48 {
49     if (v1 == 0 || v2 == 0)
50         return 0;
51     if (v1 < 0)
52         return (v2 > 0) ? v2 : 0;
53     if (v2 < 0)
54         return (v1 > 0) ? v1 : 0;
55     return (v1 < v2) ? v1 : v2;
56 }
57 
58 /*
59  * Return the higher of 2 values, with 'max' as the maximum possible value (ie, limit).
60  */
61 template<typename T>
62 static inline
carla_maxLimited(const T & v1,const T & v2,const T & max)63 const T& carla_maxLimited(const T& v1, const T& v2, const T& max) noexcept
64 {
65     return (v1 >= max || v2 >= max) ? max : (v1 > v2 ? v1 : v2);
66 }
67 
68 /*
69  * Return the higher negative of 2 values.
70  * If one of the values is zero, returns zero.
71  * If one value is positive but the other negative, returns the negative.
72  * Returned value is guaranteed to be <= 0.
73  */
74 template<typename T>
75 static inline
carla_maxNegative(const T & v1,const T & v2)76 T carla_maxNegative(const T& v1, const T& v2) noexcept
77 {
78     if (v1 == 0 || v2 == 0)
79         return 0;
80     if (v1 > 0)
81         return (v2 < 0) ? v2 : 0;
82     if (v2 > 0)
83         return (v1 < 0) ? v1 : 0;
84     return (v1 > v2) ? v1 : v2;
85 }
86 
87 /*
88  * Return a value between 'min' and 'max'.
89  */
90 template<typename T>
91 static inline
carla_fixedValue(const T & min,const T & max,const T & value)92 const T& carla_fixedValue(const T& min, const T& max, const T& value) noexcept
93 {
94     CARLA_SAFE_ASSERT_RETURN(max > min, min);
95 
96     if (value <= min)
97         return min;
98     if (value >= max)
99         return max;
100     return value;
101 }
102 
103 /*
104  * Get next power of 2.
105  */
106 static inline
carla_nextPowerOf2(uint32_t size)107 uint32_t carla_nextPowerOf2(uint32_t size) noexcept
108 {
109     CARLA_SAFE_ASSERT_RETURN(size > 0, 0);
110 
111     // http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2
112     --size;
113     size |= size >> 1;
114     size |= size >> 2;
115     size |= size >> 4;
116     size |= size >> 8;
117     size |= size >> 16;
118     return ++size;
119 }
120 
121 /*
122  * Safely check if 2 numbers are equal.
123  */
124 template<typename T>
125 static inline
carla_isEqual(const T & v1,const T & v2)126 bool carla_isEqual(const T& v1, const T& v2)
127 {
128     return std::abs(v1-v2) < std::numeric_limits<T>::epsilon();
129 }
130 
131 /*
132  * Safely check if 2 numbers are not equal.
133  */
134 template<typename T>
135 static inline
carla_isNotEqual(const T & v1,const T & v2)136 bool carla_isNotEqual(const T& v1, const T& v2)
137 {
138     return std::abs(v1-v2) >= std::numeric_limits<T>::epsilon();
139 }
140 
141 /*
142  * Safely check if a number is zero.
143  */
144 template<typename T>
145 static inline
carla_isZero(const T & value)146 bool carla_isZero(const T& value)
147 {
148     return std::abs(value) < std::numeric_limits<T>::epsilon();
149 }
150 
151 /*
152  * Safely check if a number is not zero.
153  */
154 template<typename T>
155 static inline
carla_isNotZero(const T & value)156 bool carla_isNotZero(const T& value)
157 {
158     return std::abs(value) >= std::numeric_limits<T>::epsilon();
159 }
160 
161 // --------------------------------------------------------------------------------------------------------------------
162 // math functions (extended)
163 
164 /*
165  * Add float array values to another float array.
166  */
167 static inline
carla_addFloats(float dest[],const float src[],const std::size_t count)168 void carla_addFloats(float dest[], const float src[], const std::size_t count) noexcept
169 {
170     CARLA_SAFE_ASSERT_RETURN(dest != nullptr,);
171     CARLA_SAFE_ASSERT_RETURN(src != nullptr,);
172     CARLA_SAFE_ASSERT_RETURN(count > 0,);
173 
174     for (std::size_t i=0; i<count; ++i)
175         *dest++ += *src++;
176 }
177 
178 /*
179  * Copy float array values to another float array.
180  */
181 static inline
carla_copyFloats(float dest[],const float src[],const std::size_t count)182 void carla_copyFloats(float dest[], const float src[], const std::size_t count) noexcept
183 {
184     CARLA_SAFE_ASSERT_RETURN(dest != nullptr,);
185     CARLA_SAFE_ASSERT_RETURN(src != nullptr,);
186     CARLA_SAFE_ASSERT_RETURN(count > 0,);
187 
188     std::memcpy(dest, src, count*sizeof(float));
189 }
190 
191 /*
192  * Fill a float array with a single float value.
193  */
194 static inline
carla_fillFloatsWithSingleValue(float data[],const float & value,const std::size_t count)195 void carla_fillFloatsWithSingleValue(float data[], const float& value, const std::size_t count) noexcept
196 {
197     CARLA_SAFE_ASSERT_RETURN(data != nullptr,);
198     CARLA_SAFE_ASSERT_RETURN(count > 0,);
199 
200     if (carla_isZero(value))
201     {
202         std::memset(data, 0, count*sizeof(float));
203     }
204     else
205     {
206         for (std::size_t i=0; i<count; ++i)
207             *data++ = value;
208     }
209 }
210 
211 /*
212  * Clear a float array.
213  */
214 static inline
carla_zeroFloats(float floats[],const std::size_t count)215 void carla_zeroFloats(float floats[], const std::size_t count) noexcept
216 {
217     CARLA_SAFE_ASSERT_RETURN(floats != nullptr,);
218     CARLA_SAFE_ASSERT_RETURN(count > 0,);
219 
220     std::memset(floats, 0, count*sizeof(float));
221 }
222 
223 // --------------------------------------------------------------------------------------------------------------------
224 
225 /*
226  * Fill an array with a fixed value, floating-point version.
227  */
228 template <>
229 inline
carla_fill(float data[],const float & value,const std::size_t count)230 void carla_fill<float>(float data[], const float& value, const std::size_t count) noexcept
231 {
232     carla_fillFloatsWithSingleValue(data, value, count);
233 }
234 
235 /*
236  * Find the highest absolute and normalized value within a float array.
237  */
238 static inline
carla_findMaxNormalizedFloat(const float floats[],const std::size_t count)239 float carla_findMaxNormalizedFloat(const float floats[], const std::size_t count)
240 {
241     CARLA_SAFE_ASSERT_RETURN(floats != nullptr, 0.0f);
242     CARLA_SAFE_ASSERT_RETURN(count > 0, 0.0f);
243 
244     static const float kEmptyFloats[8192] = { 0.0f };
245 
246     if (count <= 8192 && std::memcmp(floats, kEmptyFloats, count) == 0)
247         return 0.0f;
248 
249     float tmp, maxf2 = std::abs(floats[0]);
250 
251     for (std::size_t i=1; i<count; ++i)
252     {
253         tmp = std::abs(*floats++);
254 
255         if (tmp > maxf2)
256             maxf2 = tmp;
257     }
258 
259     if (maxf2 > 1.0f)
260         maxf2 = 1.0f;
261 
262     return maxf2;
263 }
264 
265 /*
266  * Multiply an array with a fixed value, float-specific version.
267  */
268 static inline
carla_multiply(float data[],const float & multiplier,const std::size_t count)269 void carla_multiply(float data[], const float& multiplier, const std::size_t count) noexcept
270 {
271     CARLA_SAFE_ASSERT_RETURN(data != nullptr,);
272     CARLA_SAFE_ASSERT_RETURN(count > 0,);
273 
274     if (carla_isZero(multiplier))
275     {
276         std::memset(data, 0, count*sizeof(float));
277     }
278     else
279     {
280         for (std::size_t i=0; i<count; ++i)
281             *data++ *= multiplier;
282     }
283 }
284 
285 // --------------------------------------------------------------------------------------------------------------------
286 // Missing functions in old OSX versions.
287 
288 #if ! defined(DISTRHO_UTILS_HPP_INCLUDED) && ! defined(CARLA_PROPER_CPP11_SUPPORT)
289 namespace std {
fmin(float __x,float __y)290 inline float fmin(float __x, float __y)
291   { return __builtin_fminf(__x, __y); }
fmax(float __x,float __y)292 inline float fmax(float __x, float __y)
293   { return __builtin_fmaxf(__x, __y); }
rint(float __x)294 inline float rint(float __x)
295   { return __builtin_rintf(__x); }
round(float __x)296 inline float round(float __x)
297   { return __builtin_roundf(__x); }
298 }
299 #endif
300 
301 // --------------------------------------------------------------------------------------------------------------------
302 
303 #endif // CARLA_MATH_UTILS_HPP_INCLUDED
304