3 /*-------------------------------------------------------------------------
4 * drawElements Base Portability Library
5 * -------------------------------------
7 * Copyright 2014 The Android Open Source Project
9 * Licensed under the Apache License, Version 2.0 (the "License");
10 * you may not use this file except in compliance with the License.
11 * You may obtain a copy of the License at
13 * http://www.apache.org/licenses/LICENSE-2.0
15 * Unless required by applicable law or agreed to in writing, software
16 * distributed under the License is distributed on an "AS IS" BASIS,
17 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
18 * See the License for the specific language governing permissions and
19 * limitations under the License.
23 * \brief Basic mathematical operations.
24 *//*--------------------------------------------------------------------*/
34 /* Mathematical constants. */
36 #define DE_PI 3.14159265358979324f /*!< Pi. */
37 #define DE_LOG_2 0.69314718056f /*!< log_e(2.0) */
38 #define DE_INV_LOG_2 1.44269504089f /*!< 1.0 / log_e(2.0) */
39 #define DE_E 2.71828182845904523536f /*!< e. */
40 #define DE_LOG2_E 1.44269504088896340736f /*!< log_2(e). */
41 #define DE_INV_LOG2_E 0.69314718055994530942f /*!< 1.0 / log_2(e). */
43 #define DE_PI_DOUBLE 3.14159265358979323846 /*!< Pi as a double. */
44 #define DE_PI_16BIT 0x4248 /*!< Pi. as a float16b */
46 /* Rounding mode control. */
48 typedef enum deRoundingMode_e
50 DE_ROUNDINGMODE_TO_NEAREST_EVEN = 0,
51 DE_ROUNDINGMODE_TO_ZERO,
52 DE_ROUNDINGMODE_TO_POSITIVE_INF,
53 DE_ROUNDINGMODE_TO_NEGATIVE_INF,
58 deRoundingMode deGetRoundingMode (void);
59 deBool deSetRoundingMode (deRoundingMode mode);
61 void deMath_selfTest (void);
63 /* Float properties */
65 /* \note The NaN test probably won't work with -ffast-math */
67 DE_INLINE int deFloatIsInf (float x) { return (x > FLT_MAX) - (x < -FLT_MAX); }
68 DE_INLINE deBool deFloatIsNaN (float x) { return (x != x); }
70 DE_INLINE int deIsInf (double x) { return (x > DBL_MAX) - (x < -DBL_MAX); }
71 DE_INLINE deBool deIsNaN (double x) { return (x != x); }
73 DE_INLINE deUint32 deFloatBitsToUint32(float x)
76 deMemcpy((void *)&bits, (void *)&x, 4);
80 DE_INLINE deUint64 deDoubleBitsToUint64(double x)
83 deMemcpy((void *)&bits, (void *)&x, 8);
87 DE_INLINE deBool deFloatIsPositiveZero(float x)
89 return x == 0 && (deFloatBitsToUint32(x) >> 31) == 0;
92 DE_INLINE deBool deDoubleIsPositiveZero(double x)
94 return x == 0 && (deDoubleBitsToUint64(x) >> 63) == 0;
97 DE_INLINE deBool deFloatIsNegativeZero(float x)
99 return x == 0 && (deFloatBitsToUint32(x) >> 31) != 0;
102 DE_INLINE deBool deDoubleIsNegativeZero(double x)
104 return x == 0 && (deDoubleBitsToUint64(x) >> 63) != 0;
107 DE_INLINE deBool deFloatIsIEEENaN(float x)
109 deUint32 e = (deFloatBitsToUint32(x) & 0x7f800000u) >> 23;
110 deUint32 m = (deFloatBitsToUint32(x) & 0x007fffffu);
111 return e == 0xff && m != 0;
114 DE_INLINE deBool deDoubleIsIEEENaN(double x)
116 deUint64 e = (deDoubleBitsToUint64(x) & 0x7ff0000000000000ull) >> 52;
117 deUint64 m = (deDoubleBitsToUint64(x) & 0x000fffffffffffffull);
118 return e == 0x7ff && m != 0;
121 /* \note The definition used for signaling NaN here is valid for ARM and
122 * x86 but possibly not for other platforms.
124 * These are defined as overloads so that they can be used in templated
125 * code without risking a type conversion which would triggern an exception
126 * on a signaling NaN. We don't use deIsNan in these helpers because they
127 * do a comparison operation which may also trigger exceptions.
129 DE_INLINE deBool deFloatIsSignalingNaN(float x)
131 return deFloatIsIEEENaN(x) && (deFloatBitsToUint32(x) & (1u << 22)) == 0;
134 DE_INLINE deBool deDoubleIsSignalingNaN(double x)
136 return deDoubleIsIEEENaN(x) && (deDoubleBitsToUint64(x) & (1ull << 51)) == 0;
139 DE_INLINE deBool deFloatIsQuietNaN(float x)
141 return deFloatIsIEEENaN(x) && (deFloatBitsToUint32(x) & (1u << 22)) != 0;
144 DE_INLINE deBool deDoubleIsQuietNaN(double x)
146 return deDoubleIsIEEENaN(x) && (deDoubleBitsToUint64(x) & (1ull << 51)) != 0;
149 /* Basic utilities. */
151 DE_INLINE float deFloatAbs (float x) { return (x >= 0.0f) ? x : -x; }
152 DE_INLINE float deFloatMin (float a, float b) { return (a <= b) ? a : b; }
153 DE_INLINE float deFloatMax (float a, float b) { return (a >= b) ? a : b; }
154 DE_INLINE float deFloatClamp (float x, float mn, float mx) { return (x <= mn) ? mn : ((x >= mx) ? mx : x); }
156 DE_INLINE double deAbs (double x) { return (x >= 0.0) ? x : -x; }
157 DE_INLINE double deMin (double a, double b) { return (a <= b) ? a : b; }
158 DE_INLINE double deMax (double a, double b) { return (a >= b) ? a : b; }
159 DE_INLINE double deClamp (double x, double mn, double mx) { return (x <= mn) ? mn : ((x >= mx) ? mx : x); }
161 /* Utility functions. */
163 DE_INLINE float deFloatSign (float a) { return (a == 0.0f) ? 0.0f : ((a > 0.0f) ? +1.0f : -1.0f); }
164 DE_INLINE int deFloatIntSign (float a) { return (a == 0.0f) ? 0 : ((a > 0.0f) ? +1 : -1); }
165 DE_INLINE float deFloatFloor (float a) { return (float)floor(a); }
166 DE_INLINE float deFloatCeil (float a) { return (float)ceil(a); }
167 DE_INLINE float deFloatRound (float a) { return deFloatFloor(a + 0.5f); }
168 DE_INLINE float deFloatFrac (float a) { return a - deFloatFloor(a); }
169 DE_INLINE float deFloatMod (float a, float b) { return (float)fmod(a, b); }
170 DE_INLINE float deFloatModf (float x, float* i) { double j = 0; double ret = modf(x, &j); *i = (float)j; return (float)ret; }
171 DE_INLINE float deFloatMadd (float a, float b, float c) { return (a*b) + c; }
172 DE_INLINE float deFloatTrunc (float a) { return deFloatSign(a) * deFloatFloor(deFloatAbs(a)); }
173 DE_INLINE float deFloatLdExp (float a, int exponent) { return (float)ldexp(a, exponent); }
174 DE_INLINE float deFloatFrExp (float x, int* exponent) { return (float)frexp(x, exponent); }
175 float deFloatFractExp (float x, int* exponent);
177 DE_INLINE double deSign (double x) { return deIsNaN(x) ? x : (double)((x > 0.0) - (x < 0.0)); }
178 DE_INLINE int deIntSign (double x) { return (x > 0.0) - (x < 0.0); }
179 DE_INLINE double deFloor (double a) { return floor(a); }
180 DE_INLINE double deCeil (double a) { return ceil(a); }
181 DE_INLINE double deRound (double a) { return floor(a + 0.5); }
182 DE_INLINE double deFrac (double a) { return a - deFloor(a); }
183 DE_INLINE double deMod (double a, double b) { return fmod(a, b); }
184 DE_INLINE double deModf (double x, double* i) { return modf(x, i); }
185 DE_INLINE double deMadd (double a, double b, double c) { return (a*b) + c; }
186 DE_INLINE double deTrunc (double a) { return deSign(a) * floor(fabs(a)); }
187 DE_INLINE double deLdExp (double a, int exponent) { return ldexp(a, exponent); }
188 double deRoundEven (double a);
189 DE_INLINE double deFrExp (double x, int* exponent) { return frexp(x, exponent); }
190 /* Like frexp, except the returned fraction is in range [1.0, 2.0) */
191 double deFractExp (double x, int* exponent);
193 /* Exponential functions. */
195 DE_INLINE float deFloatPow (float a, float b) { return (float)pow(a, b); }
196 DE_INLINE float deFloatExp (float a) { return (float)exp(a); }
197 DE_INLINE float deFloatLog (float a) { return (float)log(a); }
198 DE_INLINE float deFloatExp2 (float a) { return (float)exp(a * DE_LOG_2); }
199 DE_INLINE float deFloatLog2 (float a) { return (float)log(a) * DE_INV_LOG_2; }
200 DE_INLINE float deFloatSqrt (float a) { return (float)sqrt(a); }
201 DE_INLINE float deFloatRcp (float a) { return (1.0f / a); }
202 DE_INLINE float deFloatRsq (float a) { float s = (float)sqrt(a); return (s == 0.0f) ? 0.0f : (1.0f / s); }
204 DE_INLINE double dePow (double a, double b) { return pow(a, b); }
205 DE_INLINE double deExp (double a) { return exp(a); }
206 DE_INLINE double deLog (double a) { return log(a); }
207 DE_INLINE double deExp2 (double a) { return exp(a * log(2.0)); }
208 DE_INLINE double deLog2 (double a) { return log(a) / log(2.0); }
209 DE_INLINE double deSqrt (double a) { return sqrt(a); }
210 DE_INLINE double deCbrt (double a) { return deSign(a) * dePow(deAbs(a), 1.0 / 3.0); }
212 /* Geometric functions. */
214 DE_INLINE float deFloatRadians (float a) { return a * (DE_PI / 180.0f); }
215 DE_INLINE float deFloatDegrees (float a) { return a * (180.0f / DE_PI); }
216 DE_INLINE float deFloatSin (float a) { return (float)sin(a); }
217 DE_INLINE float deFloatCos (float a) { return (float)cos(a); }
218 DE_INLINE float deFloatTan (float a) { return (float)tan(a); }
219 DE_INLINE float deFloatAsin (float a) { return (float)asin(a); }
220 DE_INLINE float deFloatAcos (float a) { return (float)acos(a); }
221 DE_INLINE float deFloatAtan2 (float y, float x) { return (float)atan2(y, x); }
222 DE_INLINE float deFloatAtanOver (float yOverX) { return (float)atan(yOverX); }
223 DE_INLINE float deFloatSinh (float a) { return (float)sinh(a); }
224 DE_INLINE float deFloatCosh (float a) { return (float)cosh(a); }
225 DE_INLINE float deFloatTanh (float a) { return (float)tanh(a); }
226 DE_INLINE float deFloatAsinh (float a) { return deFloatLog(a + deFloatSqrt(a*a + 1)); }
227 DE_INLINE float deFloatAcosh (float a) { return deFloatLog(a + deFloatSqrt(a*a - 1)); }
228 DE_INLINE float deFloatAtanh (float a) { return 0.5f*deFloatLog((1.0f+a)/(1.0f-a)); }
230 DE_INLINE double deSin (double a) { return sin(a); }
231 DE_INLINE double deCos (double a) { return cos(a); }
232 DE_INLINE double deTan (double a) { return tan(a); }
233 DE_INLINE double deAsin (double a) { return asin(a); }
234 DE_INLINE double deAcos (double a) { return acos(a); }
235 DE_INLINE double deAtan2 (double y, double x) { return atan2(y, x); }
236 DE_INLINE double deAtanOver (double yOverX) { return atan(yOverX); }
237 DE_INLINE double deSinh (double a) { return sinh(a); }
238 DE_INLINE double deCosh (double a) { return cosh(a); }
239 DE_INLINE double deTanh (double a) { return tanh(a); }
240 DE_INLINE double deAsinh (double a) { return deLog(a + deSqrt(a*a + 1)); }
241 DE_INLINE double deAcosh (double a) { return deLog(a + deSqrt(a*a - 1)); }
242 DE_INLINE double deAtanh (double a) { return 0.5*deLog((1.0+a)/(1.0-a)); }
246 DE_INLINE float deFloatMix (float a, float b, float t) { return a*(1.0f-t) + b*t; }
247 DE_INLINE float deFloatStep (float limit, float val) { return (val < limit) ? 0.0f : 1.0f; }
248 DE_INLINE float deFloatSmoothStep (float e0, float e1, float v)
251 if (v <= e0) return 0.0f;
252 if (v >= e1) return 1.0f;
253 t = (v - e0) / (e1 - e0);
254 return t * t * (3.0f - 2.0f * t);
257 DE_INLINE double deMix (double a, double b, double t) { return a*(1.0-t) + b*t; }
258 DE_INLINE double deStep (double limit, double val) { return (val < limit) ? 0.0 : 1.0; }
260 /* Comparison functions. */
262 DE_INLINE deBool deFloatCmpEQ (float a, float b) { return (a == b); }
263 DE_INLINE deBool deFloatCmpNE (float a, float b) { return (a != b); }
264 DE_INLINE deBool deFloatCmpLT (float a, float b) { return (a < b); }
265 DE_INLINE deBool deFloatCmpLE (float a, float b) { return (a <= b); }
266 DE_INLINE deBool deFloatCmpGT (float a, float b) { return (a > b); }
267 DE_INLINE deBool deFloatCmpGE (float a, float b) { return (a >= b); }
269 /* Convert int to float. If the value cannot be represented exactly in native single precision format, return
270 * either the nearest lower or the nearest higher representable value, chosen in an implementation-defined manner.
272 * \note Choosing either nearest lower or nearest higher means that implementation could for example consistently
273 * choose the lower value, i.e. this function does not round towards nearest.
274 * \note Value returned is in native single precision format. For example with x86 extended precision, the value
275 * returned might not be representable in IEEE single precision float.
277 DE_INLINE float deInt32ToFloat (deInt32 x) { return (float)x; }
279 /* Convert to float. If the value cannot be represented exactly in IEEE single precision floating point format,
280 * return the nearest lower (round towards negative inf). */
281 float deInt32ToFloatRoundToNegInf (deInt32 x);
283 /* Convert to float. If the value cannot be represented exactly IEEE single precision floating point format,
284 * return the nearest higher (round towards positive inf). */
285 float deInt32ToFloatRoundToPosInf (deInt32 x);
287 /* Conversion to integer. */
289 DE_INLINE deInt32 deChopFloatToInt32 (float x) { return (deInt32)x; }
290 DE_INLINE deInt32 deFloorFloatToInt32 (float x) { return (deInt32)(deFloatFloor(x)); }
291 DE_INLINE deInt32 deCeilFloatToInt32 (float x) { return (deInt32)(deFloatCeil(x)); }
293 DE_INLINE deInt32 deChopToInt32 (double x) { return (deInt32)x; }
294 DE_INLINE deInt32 deFloorToInt32 (double x) { return (deInt32)(deFloor(x)); }
295 DE_INLINE deInt32 deCeilToInt32 (double x) { return (deInt32)(deCeil(x)); }
297 /* Arithmetic round */
298 DE_INLINE deInt16 deRoundFloatToInt16 (float x) { if(x >= 0.0f) return (deInt16)(x + 0.5f); else return (deInt16)(x - 0.5f); }
299 DE_INLINE deInt32 deRoundFloatToInt32 (float x) { if(x >= 0.0f) return (deInt32)(x + 0.5f); else return (deInt32)(x - 0.5f); }
300 DE_INLINE deInt64 deRoundFloatToInt64 (float x) { if(x >= 0.0f) return (deInt64)(x + 0.5f); else return (deInt64)(x - 0.5f); }
302 DE_INLINE deInt16 deRoundToInt16 (double x) { if(x >= 0.0) return (deInt16)(x + 0.5); else return (deInt16)(x - 0.5); }
303 DE_INLINE deInt32 deRoundToInt32 (double x) { if(x >= 0.0) return (deInt32)(x + 0.5); else return (deInt32)(x - 0.5); }
304 DE_INLINE deInt64 deRoundToInt64 (double x) { if(x >= 0.0) return (deInt64)(x + 0.5); else return (deInt64)(x - 0.5); }
308 #endif /* _DEMATH_H */