libcm/cmMath.h
2012-10-29 20:52:39 -07:00

68 wiersze
2.2 KiB
C

#ifndef cmMath_h
#define cmMath_h
double cmX80ToDouble( unsigned char s[10] );
void cmDoubleToX80( double v, unsigned char s[10] );
bool cmIsPowerOfTwo( unsigned i );
unsigned cmNextPowerOfTwo( unsigned i );
unsigned cmNearPowerOfTwo( unsigned i );
bool cmIsOddU( unsigned v );
bool cmIsEvenU( unsigned v );
unsigned cmNextOddU( unsigned v );
unsigned cmPrevOddU( unsigned v );
unsigned cmNextEvenU( unsigned v );
unsigned cmPrevEvenU( unsigned v );
// modified bessel function of first kind, order 0
// ref: orfandis appendix B io.m
double cmBessel0( double x );
//=================================================================
// The following elliptic-related function approximations come from
// Parks & Burrus, Digital Filter Design, Appendix program 9, pp. 317-326
// which in turn draws directly on other sources
// calculate complete elliptic integral (quarter period) K
// given *complimentary* modulus kc
cmReal_t cmEllipK( cmReal_t kc );
// calculate elliptic modulus k
// given ratio of complete elliptic integrals r = K/K'
// (solves the "degree equation" for fixed N = K*K1'/K'K1)
cmReal_t cmEllipDeg( cmReal_t r );
// calculate arc elliptic tangent u (elliptic integral of the 1st kind)
// given argument x = sc(u,k) and *complimentary* modulus kc
cmReal_t cmEllipArcSc( cmReal_t x, cmReal_t kc );
// calculate Jacobi elliptic functions sn, cn, and dn
// given argument u and *complimentary* modulus kc
cmRC_t cmEllipJ( cmReal_t u, cmReal_t kc, cmReal_t* sn, cmReal_t* cn, cmReal_t* dn );
//=================================================================
// bilinear transform
// z = (2*sr + s)/(2*sr - s)
cmRC_t cmBlt( unsigned n, cmReal_t sr, cmReal_t* rp, cmReal_t* ip );
//=================================================================
// Pitch conversion
unsigned cmHzToMidi( double hz );
float cmMidiToHz( unsigned midi );
//=================================================================
// Floating point byte swapping
unsigned cmFfSwapFloatToUInt( float v );
float cmFfSwapUIntToFloat( unsigned v );
unsigned long long cmFfSwapDoubleToULLong( double v );
double cmFfSwapULLongToDouble( unsigned long long v );
#endif