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 85