qwt3d_helper.h

#ifndef __HELPER_H__
#define __HELPER_H__
 
#include <math.h>
#include <float.h>
#include <vector>
#include <algorithm>
 
namespace {
// Returns the minimum of two double values
inline double Min_(double a, double b)
{
    return (a < b) ? a : b;
}
}
 
namespace Qwt3D {
 
// Checks if a value is practically zero (within floating-point epsilon)
inline bool isPracticallyZero(double a, double b = 0)
{
    if (!b)
        return (fabs(a) <= DBL_MIN);
 
    return (fabs(a - b) <= Min_(fabs(a), fabs(b)) * DBL_EPSILON);
}
 
// Rounds a double value to the nearest integer
inline int round(double d)
{
    return (d > 0) ? int(d + 0.5) : int(d - 0.5);
}
 
} // ns
 
#endif