21 #ifdef fl_math_h_cyclic_include     22 #  include "/usr/include/math.h"    28 #  define fl_math_h_cyclic_include     30 #  undef fl_math_h_cyclic_include     38 #    define M_PI            3.14159265358979323846    39 #    define M_PI_2          1.57079632679489661923    40 #    define M_PI_4          0.78539816339744830962    41 #    define M_1_PI          0.31830988618379067154    42 #    define M_2_PI          0.63661977236758134308    46 #    define M_SQRT2         1.41421356237309504880    47 #    define M_SQRT1_2       0.70710678118654752440    50 #  if (defined(WIN32) || defined(CRAY)) && !defined(__MINGW32__) && !defined(__MWERKS__)    52 inline double rint(
double v) {
return floor(v+.5);}
    53 inline double copysign(
double a, 
double b) {
return b<0 ? -a : a;}
    55 #  endif // (WIN32 || CRAY) && !__MINGW32__ && !__MWERKS__