prj/tech/libsrc/matrix/mxsymd.h

   1 // $Header: x:/prj/tech/libsrc/matrix/RCS/mxsymd.h 1.3 1997/08/11 18:40:51 dc Exp $
   2
   3 // symmetric octant based sin/cos
   4 // ie. they relativize the fixang into a 0-0x2000 first quadrant value
   5 //   then flip sin/cos and/on pos/neg
   6 // this guarantees that cos45==cos315 and other symmetries
   7
   8 #ifdef __cplusplus
   9 extern "C"
  10 {
  11 #endif
  12
  13 double mxd_sym_sin(mxs_ang ang);
  14 double mxd_sym_cos(mxs_ang ang);
  15 void mxd_sym_sincos(mxs_ang ang,double *s, double *c);
  16
  17 // these are a little slower, so they are there own calls
  18 // however, you can #define USE_SYMMETRIC_TRIG before including mxsymd.h
  19 // and the usual functions will be #defined to these
  20 // make sure you include this file (mxsym) after matrix itself
  21
  22 #ifdef USE_SYMMETRIC_TRIG
  23 #define mxd_sin     mxd_sym_sin
  24 #define mxd_cos     mxd_sym_cos
  25 #define mxd_sincos  mxd_sym_sincos
  26 #endif
  27
  28 #ifdef __cplusplus
  29 };
  30 #endif
  31