ale_math.h

   1 // Copyright 2002, 2003, 2004, 2005, 2006 David Hilvert <dhilvert@auricle.dyndns.org>,
   2 //                                                      <dhilvert@ugcs.caltech.edu>
   3
   4 /*  This file is part of the Anti-Lamenessing Engine.
   5
   6     The Anti-Lamenessing Engine is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 3 of the License, or
   9     (at your option) any later version.
  10
  11     The Anti-Lamenessing Engine is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with the Anti-Lamenessing Engine; if not, write to the Free Software
  18     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19 */
  20
  21 #ifndef __ale_math_h__
  22 #define __ale_math_h__
  23
  24 /*
  25  * Certain versions of Mac OSX may disable math.h definitions of is*() macros
  26  * when iostream is included, so we include the latter here.
  27  */
  28
  29 #include <math.h>
  30 #include <iostream>
  31
  32 /*
  33  * isnan() and isinf() code logic are based on those noted in the GNU Autoconf
  34  * manual, by the Free Software Foundation:
  35  *
  36  * http://www.gnu.org/software/autoconf/manual/html_node/Function-Portability.html
  37  *
  38  * As C++ is available here, we use C++ overloading instead of sizeof()
  39  * switches to handle different types.
  40  */
  41
  42 #define FIXED16 4
  43 #define FIXED32 5
  44
  45
  46 #if ALE_COLORS == FIXED16 || ALE_COLORS == FIXED32 \
  47  || ALE_COORDINATES == FIXED16 || ALE_COORDINATES == FIXED32
  48
  49 /*
  50  * Since we need custom isnan and isinf for fixed-point values, we disable any
  51  * such macros provided.
  52  */
  53
  54 #undef isnan
  55 #undef isinf
  56
  57 #endif
  58
  59 #undef FIXED16
  60 #undef FIXED32
  61
  62 #ifndef isnan
  63 # define isnan(x) ale_isnan(x)
  64 static inline int ale_isnan(float       x) { return x != x; }
  65 static inline int ale_isnan(double      x) { return x != x; }
  66 static inline int ale_isnan(long double x) { return x != x; }
  67 #endif
  68
  69 #ifndef isinf
  70 # define isinf(x) ale_isinf(x)
  71 static inline int ale_isinf(float       x) { return isnan (x - x); }
  72 static inline int ale_isinf(double      x) { return isnan (x - x); }
  73 static inline int ale_isinf(long double x) { return isnan (x - x); }
  74 #endif
  75
  76 #endif