mapInt.c

/*
 * @file mapInt.c
 *
 * @author Andy Lindsay
 *
 * @version 1.1.8
 *
 * @copyright Copyright (C) Parallax, Inc. 2018.  See end of file for
 * terms of use (MIT License).
 *
 * @brief mapInt function source, see simpletools.h for documentation.
 *
 * @detail Please submit bug reports, suggestions, and improvements to
 * this code to editor@parallax.com.
 */
 
 
 
#include "simpletools.h"
 
 
 
int mapInt(int value, int fromMin, int fromMax, int toMin, int toMax) 
{
  //   n - numerator
  //   d - denomenator
  // irt - integer rounding term
  
  int n = (value - fromMin) * (toMax - toMin);
  int d = (fromMax - fromMin);
  
  int irt = d / 2;
  if( ( (n > 0) && (d < 0) ) || ( (n < 0) && (d > 0)))
  {
    irt = - irt;
  }
  
  int val = (n + irt) / d;    
      
  return val + toMin;
}