/*------------------------------------------------------------------------------*/
/** 
*  \file   config.h
*  \brief  Main configuration file.
*  \author Gabriel Peyré
*  \date   2004
*/ 
/*------------------------------------------------------------------------------*/

#ifndef _GW_CONFIG_H_
#define _GW_CONFIG_H_

#define INLINE __inline

//-------------------------------------------------------------------------
/** \name debug & inline directive */
//-------------------------------------------------------------------------
//@{ 
#ifdef _DEBUG
	#ifndef GW_DEBUG
		#define GW_DEBUG
	#endif // GW_DEBUG
#endif // _DEBUG
// #undef GW_DEBUG
//@}

//-------------------------------------------------------------------------
/** \name numerical macros */
//-------------------------------------------------------------------------
//@{
#undef		MIN
#undef		MAX
#define		MIN(a, b)       ((a) < (b) ? (a) : (b))			//!<	Returns the min value between a and b
#define		MAX(a, b)       ((a) > (b) ? (a) : (b))			//!<	Returns the max value between a and b
#define		MAXMAX(a,b,c)   ((a) > (b) ? MAX (a,c) : MAX (b,c))
#define		GW_MIN(a, b)       MIN(a,b)						//!<	Returns the min value between a and b
#undef		GW_MAX	// already defined by Windows.h ...
#define		GW_MAX(a, b)       MAX(a,b)						//!<	Returns the max value between a and b
#define		GW_MAXMAX(a,b,c)   MAXMAX(a,b,c)

#define GW_SCALE_01(x,rMin,rMax) ((x-rMin)/(rMax-rMin))

#define		GW_ABS(a)       ((a) > 0 ? (a) : -(a))			//!<	Returns the absolute value a
#define		GW_SIGN(a)       ((a) > 0 ? 1 : -1)				//!<	Returns the sign of a
#define		SQR(x)			((x)*(x))						//!<	Returns x square
#define		CUBE(x)			((x)*(x)*(x))					//!<	Returns x cube
#define		GW_SQR(x)		SQR(x)							//!<	Returns x square
#define		GW_CUBE(x)		CUBE(x)							//!<	Returns x cube

#define GW_CLAMP_01(x)	if( (x)<0 ) x=0; if( (x)>1 ) x=1
#define GW_CLAMP(x, a,b)	if( (x)<a ) x=a; if( (x)>b ) x=b

#define GW_SWAP(x,y) x^=y; y^=x; x^=y
#define GW_ORDER(x,y) if(x>y){ GW_SWAP(x,y); }
//@}

//-------------------------------------------------------------------------
/** \name generic macros */
//-------------------------------------------------------------------------
//@{
/** a random number in [0-1] */
#define GW_RAND ((double) (rand()%10000))/10000
/** a random number in [a,b] */
#define GW_RAND_RANGE(a,b) (a)+((b)-(a))*((GW_Float) (rand()%10000))/10000
/** delete a single pointer */
#define GW_DELETE(p) {if (p!=NULL) delete p; p=NULL;}
/** delete an array pointer */
#define GW_DELETEARRAY(p) {if (p!=NULL) delete [] p; p=NULL;}
//@}

//-------------------------------------------------------------------------
/** \name some constants */
//-------------------------------------------------------------------------
//@{
#define GW_True  true
#define GW_False false
/** to make aproximate computations (derivation, GW_Float comparaisons ...) */
#define GW_EPSILON 1e-9
/** very big number */
#define GW_INFINITE 1e9
//@}

//-------------------------------------------------------------------------
/** \name numerical  constants */
//-------------------------------------------------------------------------
//@{
/** pi */
#define GW_PI		3.1415926535897932384626433832795028841971693993751f
/** pi/2 */
#define GW_HALFPI	1.57079632679489661923f
/** 2*pi */
#define GW_TWOPI	6.28318530717958647692f
/** 1/pi */
#define GW_INVPI	0.31830988618379067154f
/** 180/pi */
#define GW_RADTODEG(x)	(x)*57.2957795130823208768f
/** pi/180 */
#define GW_DEGTORAD(x)	(x)*0.01745329251994329577f
/** e */
#define GW_EXP		2.71828182845904523536f
/** 1/log10(2) */
#define GW_ILOG2	3.32192809488736234787f
/** 1/3 */
#define GW_INV3		0.33333333333333333333f
/** 1/6 */
#define GW_INV6		0.16666666666666666666f
/** 1/9 */
#define GW_INV7		0.14285714285714285714f
/** 1/9 */
#define GW_INV9		0.11111111111111111111f
/** 1/255 */
#define GW_INV255	0.00392156862745098039f
/** sqrt(2) */
#define GW_SQRT2    1.41421356237f
//@}

//-------------------------------------------------------------------------
/** \name assertion macros */
//-------------------------------------------------------------------------
//@{
#ifdef GW_DEBUG
	#define GW_ASSERT(expr) _ASSERT(expr)
	#define GW_DEBUG_ONLY(expr) expr
#else
	#define GW_ASSERT(expr)	// if(!(expr)) cerr << "Error in file " << __FILE__ << " line " << __LINE__ << "." << endl 
	#define GW_DEBUG_ONLY(expr)
#endif // GW_DEBUG
//@}

INLINE
int log2(int n)
{
	int x = 0;
	while (n > 1) 
	{
		x++;
		n /= 2;
	}
	return x;
}

INLINE
int cmp(double a, double b)
{	
	if (a < b)
		return -1;
	if (a == b)
		return 0;
	return 1;
}

#endif // _GW_CONFIG_H_