diff options
| -rw-r--r-- | src/gallium/auxiliary/util/u_math.h | 49 |
1 files changed, 32 insertions, 17 deletions
diff --git a/src/gallium/auxiliary/util/u_math.h b/src/gallium/auxiliary/util/u_math.h index 30e6e2f6b37..167fc83dc1d 100644 --- a/src/gallium/auxiliary/util/u_math.h +++ b/src/gallium/auxiliary/util/u_math.h @@ -53,11 +53,11 @@ __inline double ceil(double val) { double ceil_val; - if((val - (long) val) == 0) { + if ((val - (long) val) == 0) { ceil_val = val; } else { - if(val > 0) { + if (val > 0) { ceil_val = (long) val + 1; } else { @@ -73,11 +73,11 @@ __inline double floor(double val) { double floor_val; - if((val - (long) val) == 0) { + if ((val - (long) val) == 0) { floor_val = val; } else { - if(val > 0) { + if (val > 0) { floor_val = (long) val; } else { @@ -189,7 +189,10 @@ static INLINE double log2( double x ) extern float pow2_table[POW2_TABLE_SIZE]; - +/** + * Initialize math module. This should be called before using any + * other functions in this module. + */ extern void util_init_math(void); @@ -220,7 +223,7 @@ util_fast_exp2(float x) if(x > 129.00000f) return 3.402823466e+38f; - if(x < -126.99999f) + if (x < -126.99999f) return 0.0f; ipart = (int32_t) x; @@ -228,7 +231,8 @@ util_fast_exp2(float x) /* same as * epart.f = (float) (1 << ipart) - * but faster and without integer overflow for ipart > 31 */ + * but faster and without integer overflow for ipart > 31 + */ epart.i = (ipart + 127 ) << 23; mpart = pow2_table[POW2_TABLE_OFFSET + (int)(fpart * POW2_TABLE_SCALE)]; @@ -254,6 +258,9 @@ util_fast_exp(float x) extern float log2_table[LOG2_TABLE_SIZE]; +/** + * Fast approximation to log2(x). + */ static INLINE float util_fast_log2(float x) { @@ -267,6 +274,9 @@ util_fast_log2(float x) } +/** + * Fast approximation to x^y. + */ static INLINE float util_fast_pow(float x, float y) { @@ -274,7 +284,6 @@ util_fast_pow(float x, float y) } - /** * Floor(x), returned as int. */ @@ -284,8 +293,8 @@ util_ifloor(float f) int ai, bi; double af, bf; union fi u; - af = (3 << 22) + 0.5 + (double)f; - bf = (3 << 22) + 0.5 - (double)f; + af = (3 << 22) + 0.5 + (double) f; + bf = (3 << 22) + 0.5 - (double) f; u.f = (float) af; ai = u.i; u.f = (float) bf; bi = u.i; return (ai - bi) >> 1; @@ -305,9 +314,9 @@ util_iround(float f) #elif defined(PIPE_CC_MSVC) && defined(PIPE_ARCH_X86) int r; _asm { - fld f - fistp r - } + fld f + fistp r + } return r; #else if (f >= 0.0f) @@ -340,7 +349,7 @@ static INLINE unsigned long ffs( unsigned long u ) { unsigned long i; - if(_BitScanForward(&i, u)) + if (_BitScanForward(&i, u)) return i + 1; else return 0; @@ -351,7 +360,7 @@ unsigned ffs( unsigned u ) { unsigned i; - if( u == 0 ) { + if (u == 0) { return 0; } @@ -378,7 +387,10 @@ fui( float f ) } - +/** + * Convert ubyte to float in [0, 1]. + * XXX a 256-entry lookup table would be slightly faster. + */ static INLINE float ubyte_to_float(ubyte ub) { @@ -422,7 +434,10 @@ util_logbase2(unsigned n) } - +/** + * Clamp X to [MIN, MAX]. + * This is a macro to allow float, int, uint, etc. types. + */ #define CLAMP( X, MIN, MAX ) ( (X)<(MIN) ? (MIN) : ((X)>(MAX) ? (MAX) : (X)) ) #define MIN2( A, B ) ( (A)<(B) ? (A) : (B) ) |