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Diffstat (limited to 'src/gallium/auxiliary/util/u_math.h')
-rw-r--r--src/gallium/auxiliary/util/u_math.h75
1 files changed, 54 insertions, 21 deletions
diff --git a/src/gallium/auxiliary/util/u_math.h b/src/gallium/auxiliary/util/u_math.h
index e5003af01d..57410e78b0 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);
@@ -216,23 +219,24 @@ util_fast_exp2(float x)
int32_t ipart;
float fpart, mpart;
union fi epart;
-
+
if(x > 129.00000f)
return 3.402823466e+38f;
-
- if(x < -126.99999f)
+
+ if (x < -126.99999f)
return 0.0f;
ipart = (int32_t) x;
fpart = x - (float) ipart;
-
+
/* 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)];
-
+
return epart.f * mpart;
}
@@ -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)
{
@@ -409,7 +421,23 @@ float_to_ubyte(float f)
}
+/**
+ * Calc log base 2
+ */
+static INLINE unsigned
+util_logbase2(unsigned n)
+{
+ unsigned log2 = 0;
+ while (n >>= 1)
+ ++log2;
+ return log2;
+}
+
+/**
+ * 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) )
@@ -422,6 +450,11 @@ align(int value, int alignment)
return (value + alignment - 1) & ~(alignment - 1);
}
+static INLINE unsigned
+minify(unsigned value)
+{
+ return MAX2(1, value >> 1);
+}
#ifndef COPY_4V
#define COPY_4V( DST, SRC ) \