public override double intersection(Ray r)
{
float t = float.MaxValue;//(r.Direction.X * r.Direction.X + r.Direction.Y * r.Direction.Y + r.Direction.Z * r.Direction.Z);
List<poly> polynomMap = new List<poly>();
float rSquare, rInvSquare;
rSquare = size * size;
rInvSquare = invSizeSquare;
float maxEstimatedPotential = 0.0f;
float A = 0.0f;
float B = 0.0f;
float C = 0.0f;
for (int i= 0; i< centerList.Count; i++)
{
Vector3 currentPoint = centerList[i];
Vector3 vDist = currentPoint - r.Start;
float aa = 1.0f;
float bb = - 2.0f * (r.Direction.X*vDist.X + r.Direction.Y*vDist.Y + r.Direction.Z*vDist.Z);
float cc = (vDist.X*vDist.X + vDist.Y*vDist.Y + vDist.Z*vDist.Z);
float BSquareOverFourMinusC = 0.25f * bb * bb - cc;
float MinusBOverTwo = -0.5f * bb;
float ATimeInvSquare = aa * rInvSquare;
float BTimeInvSquare = bb * rInvSquare;
float CTimeInvSquare = cc * rInvSquare;
for (int j=0; j < zoneNumber - 1; j++)
{
float fDelta = BSquareOverFourMinusC + zoneTab[j].fCoef * rSquare;
if (fDelta < 0.0f)
{
break;
}
float sqrtDelta = (float)Math.Sqrt(fDelta);
float t0 = MinusBOverTwo - sqrtDelta;
float t1 = MinusBOverTwo + sqrtDelta;
poly poly0 = new poly(zoneTab[j].fGamma * ATimeInvSquare ,
zoneTab[j].fGamma * BTimeInvSquare ,
zoneTab[j].fGamma * CTimeInvSquare + zoneTab[j].fBeta,
t0,
zoneTab[j].fDeltaFInvSquare);
poly poly1 = new poly(- poly0.a, - poly0.b, - poly0.c,
t1,
-poly0.fDeltaFInvSquare);
maxEstimatedPotential += zoneTab[j].fDeltaFInvSquare;
polynomMap.Add(poly0);
polynomMap.Add(poly1);
};
}
if (polynomMap.Count < 2 || maxEstimatedPotential < 1.0f)
{
return 0;
}
polynomMap.Sort((x, y) => x.isLess(y));
maxEstimatedPotential = 0.0f;
bool bResult = false;
int it, itNext;
for(it = 0, itNext = it+1; itNext < polynomMap.Count; it = itNext, itNext++)
{
A += polynomMap[it].a;
B += polynomMap[it].b;
C += polynomMap[it].c;
maxEstimatedPotential += polynomMap[it].fDeltaFInvSquare;
if (maxEstimatedPotential < 1.0f)
{
continue;
}
float fZoneStart = polynomMap[it].fDistance;
float fZoneEnd = polynomMap[itNext].fDistance;
if (t > fZoneStart && 0.01f < fZoneEnd )
{
float fDelta = B * B - 4.0f * A * (C - 1.0f) ;
if (fDelta < 0.0f)
{
continue;
}
if(A == 0) A = float.MinValue;
float fInvA = (0.5f / A);
float fSqrtDelta = (float)Math.Sqrt(fDelta);
float t0 = fInvA * (- B - fSqrtDelta);
float t1 = fInvA * (- B + fSqrtDelta);
if ((t0 > 0.01f ) && (t0 >= fZoneStart ) && (t0 < fZoneEnd) && (t0 <= t ))
{
t = t0;
bResult = true;
}
if ((t1 > 0.01f ) && (t1 >= fZoneStart ) && (t1 < fZoneEnd) && (t1 <= t ))
{
t = t1;
bResult = true;
}
if (bResult)
{
return t;
}
}
}
return 0;
}
public int isLess(poly p)
{
if (fDistance < p.fDistance)
return -1;
else if (fDistance == p.fDistance)
return 0;
else
return 1;
}
