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 Copyright (c) 2009, Charles McGarvey
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#ifndef _MATH_HH_
#define _MATH_HH_

/**
 * @file math.hh
 * General math-related types and functions.
 */

#include <cmath>
#include <cml/cml.h>


namespace dc {


typedef double				scalar;				///< Scalar variable.

typedef cml::vector2d		vector2;
typedef cml::vector3d		vector3;
typedef cml::vector4d		vector4;

typedef cml::matrix33d_c	matrix3;
typedef cml::matrix44d_c	matrix4;

typedef cml::quaterniond_p	quaternion;

typedef cml::vector4f		color;


// Here's a simple way to check the equality of floating-point variables more
// reliably using approximation.

const scalar default_epsilon = 0.00001;		///< @see equals()


/**
 * Check the equality of scalars with a certain degree of error allowed.
 */

inline bool equals(scalar a, scalar b, scalar epsilon = default_epsilon)
{
	return std::abs(a - b) < epsilon;
}


} // namespace dc

#endif // _MATH_HH_