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#pragma once

//==============================================================================
//	Namespace
//==============================================================================
namespace Q3DStudio {

//==============================================================================
/**
 *	Wrapper class to functions that solve cubic equations.
 *
 *	The function suite is taken from Graphics Gems:
 *  Roots3And4.c
 *
 *  Utility functions to find cubic and quartic roots,
 *  coefficients are passed like this:
 *
 *      c[0] + c[1]*x + c[2]*x^2 + c[3]*x^3 + c[4]*x^4 = 0
 *
 *  The functions return the number of non-complex roots and
 *  put the values into the s array.
 *
 *  Author:         Jochen Schwarze (schwarze@isa.de)
 *
 *  Jan 26, 1990    Version for Graphics Gems
 *  Oct 11, 1990    Fixed sign problem for negative q's in SolveQuartic
 *  	    	    (reported by Mark Podlipec),
 *  	    	    Old-style function definitions,
 *  	    	    IsZero() as a macro
 *  Nov 23, 1990    Some systems do not declare acos() and cbrt() in
 *                  <math.h>, though the functions exist in the library.
 *                  If large coefficients are used, EQN_EPS should be
 *                  reduced considerably (e.g. to 1E-30), results will be
 *                  correct but multiple roots might be reported more
 *                  than once.
 */
class CCubicRoots
{
    //==============================================================================
    //	Methods
    //==============================================================================
public:
    static INT32 SolveQuadric(FLOAT inConstants[3], FLOAT outSolutions[2]);
    static INT32 SolveCubic(FLOAT inConstants[4], FLOAT outSolutions[3]);
    //		static int SolveQuartic( FLOAT c[5], FLOAT s[4] );
};

} // namespace Q3DStudio