/*
	SuperCollider real time audio synthesis system
    Copyright (c) 2002 James McCartney. All rights reserved.
	http://www.audiosynth.com

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

#ifndef _UnaryOpUGen_
#define _UnaryOpUGen_

#include "SC_Types.h"
#include "SC_Constants.h"

///////////////////////////////////////////////////////////////////////////////////////

inline bool sc_isnan(float x)
{
	return (!(x >= 0.f || x <= 0.f));
}

///////////////////////////////////////////////////////////////////////////////////////

// versions provided for float32 and float64
// did not supply template because do not want to instantiate for integers.
// all constants explicitly cast to prevent PowerPC frsp instruction generation.

///////////////////////////////////////////////////////////////////////////////////////

// this is a function for preventing pathological math operations in ugens.
// can be used at the end of a block to fix any recirculating filter values.
inline float32 zapgremlins(float32 x)
{
	float32 absx = fabs(x);
	// very small numbers fail the first test, eliminating denormalized numbers
	//    (zero also fails the first test, but that is OK since it returns zero.)
	// very large numbers fail the second test, eliminating infinities
	// Not-a-Numbers fail both tests and are eliminated.
	return (absx > (float32)1e-15 && absx < (float32)1e15) ? x : (float32)0.;
}

inline float32 sc_log2(float32 x)
{
	return log(fabs(x)) * rlog2;
}

inline float32 sc_log10(float32 x)
{
	return log10(fabs(x));
}

inline float32 sc_midicps(float32 note)
{
	return (float32)440. * pow((float32)2., (note - (float32)69.) * (float32)0.083333333333);
}

inline float32 sc_cpsmidi(float32 freq)
{
	return sc_log2(freq * (float32)0.0022727272727) * (float32)12. + (float32)69.;
}

inline float32 sc_midiratio(float32 midi)
{
	return pow((float32)2. , midi * (float32)0.083333333333);
}

inline float32 sc_ratiomidi(float32 ratio)
{
	return (float32)12. * sc_log2(ratio);
}

inline float32 sc_octcps(float32 note)
{
	return (float32)440. * pow((float32)2., note - (float32)4.75);
}

inline float32 sc_cpsoct(float32 freq)
{
	return sc_log2(freq * (float32)0.0022727272727) + (float32)4.75;
}

inline float32 sc_ampdb(float32 amp)
{
	return log10(amp) * (float32)20.;
}

inline float32 sc_dbamp(float32 db)
{
	return pow((float32)10., db * (float32).05);
}

inline float32 sc_squared(float32 x)
{
	return x * x;
}

inline float32 sc_cubed(float32 x)
{
	return x * x * x;
}

inline float32 sc_sqrt(float32 x)
{
	return x < (float32)0. ? -sqrt(-x) : sqrt(x);
}


inline float32 sc_hanwindow(float32 x)
{
	if (x < (float32)0. || x > (float32)1.) return (float32)0.;
	return (float32)0.5 - (float32)0.5 * cos(x * twopi);
}

inline float32 sc_welwindow(float32 x)
{
	if (x < (float32)0. || x > (float32)1.) return (float32)0.;
	return sin(x * pi);
}

inline float32 sc_triwindow(float32 x)
{
	if (x < (float32)0. || x > (float32)1.) return (float32)0.;
	if (x < (float32)0.5) return (float32)2. * x;
	else return (float32)-2. * x + (float32)2.;
}

inline float32 sc_bitriwindow(float32 x)
{
	float32 ax = (float32)1. - fabs(x);
	if (ax <= (float32)0.) return (float32)0.;
	return ax;
}

inline float32 sc_rectwindow(float32 x)
{
	if (x < (float32)0. || x > (float32)1.) return (float32)0.;
	return (float32)1.;
}

inline float32 sc_scurve(float32 x)
{
	if (x <= (float32)0.) return (float32)0.;
	if (x >= (float32)1.) return (float32)1.;
	return x * x * ((float32)3. - (float32)2. * x);
}

inline float32 sc_scurve0(float32 x)
{
	// assumes that x is in range
	return x * x * ((float32)3. - (float32)2. * x);
}

inline float32 sc_ramp(float32 x)
{
	if (x <= (float32)0.) return (float32)0.;
	if (x >= (float32)1.) return (float32)1.;
	return x;
}

inline float32 sc_distort(float32 x)
{
	return x / ((float32)1. + fabs(x));
}

inline float32 sc_softclip(float32 x)
{
	float32 absx = fabs(x);
	if (absx <= (float32)0.5) return x;
	else return (absx - (float32)0.25) / x;
}

// Taylor expansion out to x**9/9! factored  into multiply-adds
// from Phil Burk.
inline float32 taylorsin(float32 x)
{
	// valid range from -pi/2 to +3pi/2
	x = pi2 - fabs(pi2 - x);
	float32 x2 = x * x;
  	return x*(x2*(x2*(x2*(x2*(1.0/362880.0) 
  			- (1.0/5040.0))
            + (1.0/120.0))
            - (1.0/6.0))
            + 1.0);
}

inline float32 sc_trunc(float32 x)
{
	// truncFloat is a number which causes a loss of precision of 
	// the fractional part.
	// NOTE: this will only work if the FPU is set to round downward.
	// That is NOT the default rounding mode. SC sets it to this mode.
	float32 tmp1 = x + truncFloat;
	float32 tmp2 = tmp1 - truncFloat;
	return tmp2;
}

inline float32 sc_frac(float32 x)
{
	return x - sc_trunc(x);
}

inline float32 sc_lg3interp(float32 x1, float32 a, float32 b, float32 c, float32 d)
{
	// cubic lagrange interpolator
	float32 x0 = x1 + 1.f;
	float32 x2 = x1 - 1.f;
	float32 x3 = x1 - 2.f;
	
	float32 x03 = x0 * x3 * 0.5f;
	float32 x12 = x1 * x2 * 0.16666666666666667f;
	
	return x12 * (d * x0 - a * x3) + x03 * (b * x2 - c * x1);
}

inline float32 sc_CalcFeedback(float32 delaytime, float32 decaytime)
{
	if (delaytime == 0.f) {
		return 0.f;
	} else if (decaytime > 0.f) {
		return exp(log001 * delaytime / decaytime);
	} else if (decaytime < 0.f) {
		return -exp(log001 * delaytime / -decaytime);
	} else {
		return 0.f;
	}
}

inline float32 sc_wrap1(float32 x)
{
	if (x >= (float32) 1.) return x + (float32)-2.;
	if (x <  (float32)-1.) return x + (float32) 2.;
	return x;
}

inline float32 sc_fold1(float32 x)
{
	if (x >= (float32) 1.) return (float32) 2. - x;
	if (x <  (float32)-1.) return (float32)-2. - x;
	return x;
}


///////////////////////////////////////////////////////////////////////////////////////

inline float64 zapgremlins(float64 x)
{
	float64 absx = fabs(x);
	// very small numbers fail the first test, eliminating denormalized numbers
	//    (zero also fails the first test, but that is OK since it returns zero.)
	// very large numbers fail the second test, eliminating infinities
	// Not-a-Numbers fail both tests and are eliminated.
	return (absx > (float64)1e-15 && absx < (float64)1e15) ? x : (float64)0.;
}

inline float64 sc_log2(float64 x)
{
	return log(fabs(x)) * rlog2;
}

inline float64 sc_log10(float64 x)
{
	return log10(fabs(x));
}

inline float64 sc_midicps(float64 note)
{
	return (float64)440. * pow((float64)2., (note - (float64)69.) * (float64)0.083333333333);
}

inline float64 sc_cpsmidi(float64 freq)
{
	return sc_log2(freq * (float64)0.0022727272727) * (float64)12. + (float64)69.;
}

inline float64 sc_midiratio(float64 midi)
{
	return pow((float64)2. , midi * (float64)0.083333333333);
}

inline float64 sc_ratiomidi(float64 ratio)
{
	return (float64)12. * sc_log2(ratio);
}

inline float64 sc_octcps(float64 note)
{
	return (float64)440. * pow((float64)2., note - (float64)4.75);
}

inline float64 sc_cpsoct(float64 freq)
{
	return sc_log2(freq * (float64)0.0022727272727) + (float64)4.75;
}

inline float64 sc_ampdb(float64 amp)
{
	return log10(amp) * (float64)20.;
}

inline float64 sc_dbamp(float64 db)
{
	return pow((float64)10., db * (float64).05);
}

inline float64 sc_squared(float64 x)
{
	return x * x;
}

inline float64 sc_cubed(float64 x)
{
	return x * x * x;
}

inline float64 sc_sqrt(float64 x)
{
	return x < (float64)0. ? -sqrt(-x) : sqrt(x);
}

inline float64 sc_hanwindow(float64 x)
{
	if (x < (float64)0. || x > (float64)1.) return (float64)0.;
	return (float64)0.5 - (float64)0.5 * cos(x * twopi);
}

inline float64 sc_welwindow(float64 x)
{
	if (x < (float64)0. || x > (float64)1.) return (float64)0.;
	return sin(x * pi);
}

inline float64 sc_triwindow(float64 x)
{
	if (x < (float64)0. || x > (float64)1.) return (float64)0.;
	if (x < (float64)0.5) return (float64)2. * x;
	else return (float64)-2. * x + (float64)2.;
}

inline float64 sc_bitriwindow(float64 x)
{
	float64 ax = fabs(x);
	if (ax > (float64)1.) return (float64)0.;
	return (float64)1. - ax;
}

inline float64 sc_rectwindow(float64 x)
{
	if (x < (float64)0. || x > (float64)1.) return (float64)0.;
	return (float64)1.;
}

inline float64 sc_scurve(float64 x)
{
	if (x <= (float64)0.) return (float64)0.;
	if (x >= (float64)1.) return (float64)1.;
	return x * x * ((float64)3. - (float64)2. * x);
}

inline float64 sc_scurve0(float64 x)
{
	// assumes that x is in range
	return x * x * ((float64)3. - (float64)2. * x);
}

inline float64 sc_ramp(float64 x)
{
	if (x <= (float64)0.) return (float64)0.;
	if (x >= (float64)1.) return (float64)1.;
	return x;
}

inline float64 sc_distort(float64 x)
{
	return x / ((float64)1. + fabs(x));
}

inline float64 sc_softclip(float64 x)
{
	float64 absx = fabs(x);
	if (absx <= (float64)0.5) return x;
	else return (absx - (float64)0.25) / x;
}

// Taylor expansion out to x**9/9! factored  into multiply-adds
// from Phil Burk.
inline float64 taylorsin(float64 x)
{
	x = pi2 - fabs(pi2 - x);
	float64 x2 = x * x;
  	return x*(x2*(x2*(x2*(x2*(1.0/362880.0) 
  			- (1.0/5040.0))
            + (1.0/120.0))
            - (1.0/6.0))
            + 1.0);
}

inline float64 sc_trunc(float64 x)
{
	// truncDouble is a number which causes a loss of precision of 
	// the fractional part.
	// NOTE: this will only work if the FPU is set to round downward.
	// That is NOT the default rounding mode. SC sets it to this mode.
	float64 tmp1 = x + truncDouble;
	float64 tmp2 = tmp1 - truncDouble;
	return tmp2;
}

inline float64 sc_frac(float64 x)
{
	return x - sc_trunc(x);
}

inline float64 sc_wrap1(float64 x)
{
	if (x >= (float64) 1.) return x + (float64)-2.;
	if (x <  (float64)-1.) return x + (float64) 2.;
	return x;
}

inline float64 sc_fold1(float64 x)
{
	if (x >= (float64) 1.) return (float64) 2. - x;
	if (x <  (float64)-1.) return (float64)-2. - x;
	return x;
}

inline int32 sc_grayCode(int32 x)
{
	return x ^ (x >> 1);
}



///////////////////////////////////////////////////////////////////////////////////////

#endif