public Vector3D untransform(Vector3D a, Vector3D dest)
{
dest.X = a.dot(u);
dest.Y = a.dot(v);
dest.Z = a.dot(w);
return(dest);
}
// Lambertian! Replace with general BSDF.
public virtual void radianceEstimate(RGBColor rad, Vector3D position, Vector3D normal, float maxDist, int noPhotons)
{
//float ALPHA = 0.918f;
float MBETA = -1.953f;
float DENOMFACTOR = 1.0f / (1.0f - (float)System.Math.Exp(MBETA));
NearestPhotons np = new NearestPhotons(noPhotons, maxDist, position);
rad.set(0.0f);
// locate the nearest photons
locatePhotons(np, 1);
// if less than MINPHOTONS return
if (np.found < photontracer.SceneConstants.MIN_PHOTONS)
{
return;
}
Vector3D direction = new Vector3D();
//float mittrs = MBETA / (2.0f * (float) np.dist2[0]);
float kdenom = (float)(1.0 / (1.1 * Math.Sqrt(np.dist2[0])));
// sum irrandiance from all photons
for (int i = 1; i <= np.found; i++)
{
float cosNL;
Photon p = getPhoton(np.indices[i]);
// the toCartesian call and following if can be omitted (for speed)
// if the scene does not have any thin surfaces
p.toCartesian(direction);
cosNL = (float)direction.dot(normal);
//cosNL = -1.0f;
if (cosNL < 0.0)
{
//float gaussWeight = 1.0f - (1.0f - (float) System.Math.Exp((float) p.position.distanceSqr(position) * mittrs)) * DENOMFACTOR;
float coneWeight = 1.0f - (float)(p.position.distance(position) * kdenom);
//rad.add(p.power.scaleNew((- cosNL) * gaussWeight));
//rad.add(p.power.scaleNew((- cosNL)));
rad.add(p.power.scaleNew(coneWeight));
}
}
// estimate of density
//rad.scale(ALPHA / (float) (System.Math.PI * np.dist2[0]));
//rad.scale(1.0f / (float) (System.Math.PI * np.dist2[0]));
rad.scale(1.0f / (float)((1.0f - 2.0f / (3.0f * 1.1f)) * System.Math.PI * np.dist2[0]));
}
public override bool intersect(Ray ray, Intersection intersection)
{
double vd;
double vx;
double vy;
Vector3D orig = ray.Location.subNew(position());;
Vector3D dir = ray.direction();
/* Check if the ray lies parallel to the plane */
vd = ng.dot(dir);
if ((vd > -photontracer.SceneConstants.EPSILON) && (vd < photontracer.SceneConstants.EPSILON))
{
return(false);
}
/* Check if ray intersects plane */
double t = -((ng.x() * orig.x()) + (ng.y() * orig.y()) + (ng.z() * orig.z()) + d) / vd;
if (t < photontracer.SceneConstants.EPSILON)
{
return(false);
}
/* Check if intersection is inside the triangle */
switch (dropAxis)
{
case 0:
vx = (orig.y() + (dir.y() * t)) - v0.p.y();
vy = (orig.z() + (dir.z() * t)) - v0.p.z();
break;
case 1:
vx = (orig.x() + (dir.x() * t)) - v0.p.x();
vy = (orig.z() + (dir.z() * t)) - v0.p.z();
break;
default:
vx = (orig.x() + (dir.x() * t)) - v0.p.x();
vy = (orig.y() + (dir.y() * t)) - v0.p.y();
break;
}
double u = (edge2x * vy) - (edge2y * vx);
if ((u < 0.0) || (u > 1.0))
{
return(false);
}
double v = (edge1y * vx) - (edge1x * vy);
if ((v < 0.0) || ((u + v) > 1.0))
{
return(false);
}
Vector3D intersectionPoint;
intersectionPoint = ray.direction().scaleNew(t);
intersectionPoint.add(ray.Location);
intersection.IntersectionPoint = intersectionPoint;
intersection.IntersectedObject = this;
intersection.Lambda = t;
return(true);
}
public virtual void locatePhotonsPrecomputed(Vector3D normal, NearestPhotons np, int index)
{
double dist1, dist2;
Photon p = getPhoton(index);
if (index < halfStoredPhotons)
{
dist1 = np.position.get(p.plane) - p.position.get(p.plane);
if (dist1 > 0.0)
{
// if dist1 is positive search right plane
locatePhotonsPrecomputed(normal, np, (2 * index) + 1);
if (dist1 * dist1 < np.dist2[0])
{
locatePhotonsPrecomputed(normal, np, (2 * index));
}
}
else
{
// dist1 is negative search left first
locatePhotonsPrecomputed(normal, np, (2 * index));
if (dist1 * dist1 < np.dist2[0])
{
locatePhotonsPrecomputed(normal, np, (2 * index) + 1);
}
}
}
// compute squared distance between current photon and np.position
dist2 = p.position.distanceSqr(np.position);
//assert(p.precomputedIrradiance);
//assert(np.max == 1);
Vector3D surfaceDirection = new Vector3D();
p.surfaceToCartesian(surfaceDirection);
//System.out.println(normal.dot(surfaceDirection));
if (dist2 < np.dist2[0] && normal.dot(surfaceDirection) > 0.0)
{
// we found a photon :) Insert it in the candidate list
if (np.found < 1)
{
// heap is not full; use array
np.found++;
np.dist2[np.found] = dist2;
np.indices[np.found] = index;
}
else
{
// exchange element if necessary
if (np.dist2[0] > dist2)
{
np.dist2[1] = dist2;
np.indices[1] = index;
np.dist2[0] = dist2;
}
}
}
}
