double ParzDens_1::density ( double x )
{
int i ;
double sum, diff ;
if (spline != NULL)
return spline->evaluate ( x ) ;
sum = 0.0 ;
for (i=0 ; i<nd ; i++) {
diff = x - d[i];
sum += exp ( -0.5 * diff * diff / var ) ;
}
return sum * factor ;
}
bool CubicSpline::intersects(const CubicSpline &rt, VectorF ignoreAxis) const
{
#if 1
vector<VectorF> path1 = getSplinePoints(*this);
vector<VectorF> path2 = getSplinePoints(rt);
for(size_t i = 1; i < path1.size(); i++)
{
for(size_t j = 1; j < path2.size(); j++)
{
if(linesIntersect(path1[i - 1], path1[i], path2[j - 1], path2[j], 0))
return true;
}
}
return false;
#else
const int splitCount = 50; // number of line segments to split spline into
ignoreAxis = normalize(ignoreAxis);
for(int segmentNumber = 0; segmentNumber < splitCount; segmentNumber++)
{
float startT = (float)(segmentNumber) / splitCount;
float endT = (float)(segmentNumber + 1) / splitCount;
VectorF startP = rt.evaluate(startT);
startP -= ignoreAxis * dot(ignoreAxis, startP); // move to plane normal to ignoreAxis
VectorF endP = rt.evaluate(endT);
endP -= ignoreAxis * dot(ignoreAxis, endP); // move to plane normal to ignoreAxis
VectorF delta = endP - startP;
if(absSquared(delta) < eps * eps) // if delta is too small
{
continue;
}
// solve dot(evaluate(t), cross(ignoreAxis, delta)) == 0 and it intersects if dot(evaluate(t) - startP, delta) / dot(delta, delta) is in [0, 1] and t is in [0, 1]
VectorF normal = cross(ignoreAxis, delta);
float cubic = dot(getCubic(), normal);
float quadratic = dot(getQuadratic(), normal);
float linear = dot(getLinear(), normal);
float constant = dot(getConstant(), normal);
float intersections[3];
int intersectionCount = solveCubic(constant, linear, quadratic, cubic, intersections);
for(int i = 0; i < intersectionCount; i++)
{
float t = intersections[i];
if(t < 0 || t > 1)
{
continue;
}
float v = dot(evaluate(t) - startP, delta) / dot(delta, delta);
if(v < 0 || v > 1)
{
continue;
}
return true;
}
}
return false;
#endif
}
