dll/opengl/mesa/mmath.h

   1 /* $Id: mmath.h,v 1.5 1997/12/18 02:54:26 brianp Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  2.6
   6  * Copyright (C) 1995-1997  Brian Paul
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Library General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2 of the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Library General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Library General Public
  19  * License along with this library; if not, write to the Free
  20  * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21  */
  22
  23
  24 /*
  25  * $Log: mmath.h,v $
  26  * Revision 1.5  1997/12/18 02:54:26  brianp
  27  * added Josh Vanderhoof's float->int x86 asm code
  28  *
  29  * Revision 1.4  1997/10/15 00:36:17  brianp
  30  * renamed the FAST/REGULAR_MATH macros
  31  *
  32  * Revision 1.3  1997/09/29 22:23:54  brianp
  33  * added FAST/REGULAR_MATH macros
  34  *
  35  * Revision 1.2  1997/05/03 00:54:31  brianp
  36  * fixed a comment
  37  *
  38  * Revision 1.1  1997/05/01 01:42:38  brianp
  39  * Initial revision
  40  *
  41  */
  42
  43
  44 /*
  45  * Faster arithmetic functions.  If the FAST_MATH preprocessor symbol is
  46  * defined on the command line (-DFAST_MATH) then we'll use some (hopefully)
  47  * faster functions for sqrt(), etc.
  48  */
  49
  50
  51 #ifndef MMATH_H
  52 #define MMATH_H
  53
  54 #include <math.h>
  55
  56 #define FloatToInt(F) lrintf((F))
  57
  58 extern float gl_sqrt(float x);
  59
  60 #ifdef FAST_MATH
  61 #  define GL_SQRT(X)  gl_sqrt(X)
  62 #else
  63 #  define GL_SQRT(X)  sqrt(X)
  64 #endif
  65
  66
  67 /* Normalize a 3-element vector to unit length */
  68 #define NORMALIZE_3FV( V )                              \
  69 {                                                       \
  70    GLfloat len;                                         \
  71    len = GL_SQRT(V[0]*V[0]+V[1]*V[1]+V[2]*V[2]);        \
  72    if (len>0.0001F) {                                   \
  73       len = 1.0F / len;                                 \
  74       V[0] *= len;                                      \
  75       V[1] *= len;                                      \
  76       V[2] *= len;                                      \
  77    }                                                    \
  78 }
  79
  80
  81 extern void gl_init_math(void);
  82
  83
  84 #endif