u_math.c

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 * Copyright 2008 Tungsten Graphics, Inc., Cedar Park, Texas.
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#include "util/u_math.h"


float pow2_table[POW2_TABLE_SIZE];


static void
init_pow2_table(void)
{
   int i;
   for (i = 0; i < POW2_TABLE_SIZE; i++)
      pow2_table[i] = (float) pow(2.0, (i - POW2_TABLE_OFFSET) / POW2_TABLE_SCALE);
}


float log2_table[LOG2_TABLE_SIZE];


static void 
init_log2_table(void)
{
   unsigned i;
   for (i = 0; i < LOG2_TABLE_SIZE; i++)
      log2_table[i] = (float) log2(1.0 + i * (1.0 / LOG2_TABLE_SCALE));
}


void
util_init_math(void)
{
   static boolean initialized = FALSE;
   if (!initialized) {
      init_pow2_table();
      init_log2_table();
      initialized = TRUE;
   }
}

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