bool NaiadFoamParticle::IntersectP(const Ray &rayInc) const {
Matrix4x4 w2o_m;
w2o_m.m[0][3] = -pos.x;
w2o_m.m[1][3] = -pos.y;
w2o_m.m[2][3] = -pos.z;
Transform w2o = Transform(w2o_m);
float phi;
Point phit;
// Transform _Ray_ to object space
Ray ray;
w2o(rayInc, &ray);
// Compute quadratic sphere coefficients
float A = ray.d.x*ray.d.x + ray.d.y*ray.d.y + ray.d.z*ray.d.z;
float B = 2 * (ray.d.x*ray.o.x + ray.d.y*ray.o.y + ray.d.z*ray.o.z);
float C = ray.o.x*ray.o.x + ray.o.y*ray.o.y +
ray.o.z*ray.o.z - r*r;
// Solve quadratic equation for _t_ values
float t0, t1;
if (!Quadratic(A, B, C, &t0, &t1))
return false;
// Compute intersection distance along ray
if (t0 > ray.maxt || t1 < ray.mint)
return false;
float thit = t0;
if (t0 < ray.mint) {
thit = t1;
if (thit > ray.maxt) return false;
}
return true;
}
bool Sphere::intersect(const Ray& ray, RaySurfIntersection& res)const{
res.shp = NULL;
//Transform ray to object space
const Ray rOb = w2o(ray);
const Vector o = Vector(rOb.getOrigin().x, rOb.getOrigin().y, rOb.getOrigin().z);
const Vector d = rOb.getDir();
const float A = d.dot(d);
const float B = 2.0f * (d.dot(o));
const float C = o.dot(o) - (r * r);
struct MathUtils::QuadraticEqnRes<float> slv =
MathUtils::solveQuadratic<float>(A, B, C);
float tHitFinal = 0.0f; //After the below code this will eventually be set to
//the first hit point in front of the camera
if(slv.solCount == 0){
return false;
}else if(slv.solCount == 1){
tHitFinal = slv.sol1;
if(tHitFinal < 0.0f){
//No solutions in front of camera
return false;
}
}else{ //2 solutions
//Find smallest t value that is > 0.0f
if(slv.sol1 < 0.0f && slv.sol2 < 0.0f){
//No solutions in front of camera
return false;
}else{
//At least one hit in front of camera
slv.sol1 = slv.sol1 < 0.0f ? Constants::MAX_FLOAT_VAL : slv.sol1;
slv.sol2 = slv.sol2 < 0.0f ? Constants::MAX_FLOAT_VAL : slv.sol2;
tHitFinal = std::min<float>(slv.sol1, slv.sol2);
}
}
//Make sure hit is in front of camera
Assert(tHitFinal >= 0.0f);
res.tHit = tHitFinal;
res.locWS = ray(res.tHit);
Vector normalVecAtHit = res.locWS - o2w(Point(0.0f,0.0f,0.0f));
res.n = normalVecAtHit.getNormalized();
res.shp = this;
return true;
}
bool NaiadFoamParticle::Intersect(const Ray &rayInc, float *tHit, float *rayEpsilon,
DifferentialGeometry *dg) const {
/*const float X0 = ray.o.x;
const float Y0 = ray.o.y;
const float Z0 = ray.o.z;
const float Xd = ray.d.x;
const float Yd = ray.d.y;
const float Zd = ray.d.z;
const float Xc = pos.x;
const float Yc = pos.y;
const float Zc = pos.z;
const float B = 2.0f * (Xd * (X0 - Xc) + Yd * (Y0 - Yc) + Zd * (Z0 - Zc));
const float C = (X0-Xc)*(X0-Xc) + (Y0-Yc)*(Y0-Yc) + (Z0-Zc)*(Z0-Zc) - r*r;
const float discriminant = B*B - 4*C;
if (discriminant < 0.0f)
return false;
const float t0 = (- B - sqrt(discriminant)) / 2.0f;
const float t1 = (- B + sqrt(discriminant)) / 2.0f;
if (t0 < 0 || t0 != t0) {
return true;
}*/
Matrix4x4 w2o_m;
w2o_m.m[0][3] = -pos.x;
w2o_m.m[1][3] = -pos.y;
w2o_m.m[2][3] = -pos.z;
Transform w2o = Transform(w2o_m);
const float thetaMin = -M_PI;
const float thetaMax = 0;
const float phiMax = 2.f*M_PI;
float phi;
Point phit;
// Transform _Ray_ to object space
Ray ray;
w2o(rayInc, &ray);
// Compute quadratic sphere coefficients
float A = ray.d.x*ray.d.x + ray.d.y*ray.d.y + ray.d.z*ray.d.z;
float B = 2 * (ray.d.x*ray.o.x + ray.d.y*ray.o.y + ray.d.z*ray.o.z);
float C = ray.o.x*ray.o.x + ray.o.y*ray.o.y +
ray.o.z*ray.o.z - r*r;
// Solve quadratic equation for _t_ values
float t0, t1;
if (!Quadratic(A, B, C, &t0, &t1))
return false;
// Compute intersection distance along ray
if (t0 > ray.maxt || t1 < ray.mint)
return false;
float thit = t0;
if (t0 < ray.mint) {
thit = t1;
if (thit > ray.maxt) return false;
}
// Compute sphere hit position and $\phi$
phit = ray(thit);
rayInc.hitFoam = true;
PerspectiveCamera * cam = PerspectiveCamera::cur_cam;
Transform c2w;
cam->CameraToWorld.Interpolate(0.f, &c2w);
Transform w2c = Inverse(c2w);
Transform c2s = cam->CameraToScreen;
Transform s2r = cam->ScreenToRaster;
Point cPos = w2c(phit);
Point rPos = s2r(c2s(cPos));
int x = (int)(rPos.x + 0.5);
int y = (int)(rPos.y + 0.5);
int w = cam->film->xResolution;
int h = cam->film->yResolution;
if (x > 0 && y > 0 && x < w && y < h) {
rayInc.hitFoam = true;
/*printf("%i %i %i %i\n", x, y, w ,h);
std::cout << parent << std::endl;
std::cout << parent->parent << std::endl;
std::cout << parent->parent->foamPlane[0] << std::endl;
std::cout << parent->parent->foamPlane.size() << std::endl;
std::cout << x + y*w << std::endl;*/
//std::cout << NaiadFoam::cur->FoamPlane().size() << std::endl;
rayInc.alphaFoam = NaiadFoam::cur->FoamPlane()[x + y*w];
}
/*if (phit.x == 0.f && phit.y == 0.f) phit.x = 1e-5f * r;
phi = atan2f(phit.y, phit.x);
if (phi < 0.) phi += 2.f*M_PI;
// Find parametric representation of sphere hit
float u = phi / phiMax;
float theta = acosf(Clamp(phit.z / r, -1.f, 1.f));
float v = (theta - thetaMin) / (thetaMax - thetaMin);
// Compute sphere $\dpdu$ and $\dpdv$
float zradius = sqrtf(phit.x*phit.x + phit.y*phit.y);
float invzradius = 1.f / zradius;
float cosphi = phit.x * invzradius;
float sinphi = phit.y * invzradius;
Vector dpdu(-phiMax * phit.y, phiMax * phit.x, 0);
Vector dpdv = (thetaMax-thetaMin) *
Vector(phit.z * cosphi, phit.z * sinphi,
-r * sinf(theta));
// Compute sphere $\dndu$ and $\dndv$
Vector d2Pduu = -phiMax * phiMax * Vector(phit.x, phit.y, 0);
Vector d2Pduv = (thetaMax - thetaMin) * phit.z * phiMax *
Vector(-sinphi, cosphi, 0.);
Vector d2Pdvv = -(thetaMax - thetaMin) * (thetaMax - thetaMin) *
Vector(phit.x, phit.y, phit.z);
// Compute coefficients for fundamental forms
float E = Dot(dpdu, dpdu);
float F = Dot(dpdu, dpdv);
float G = Dot(dpdv, dpdv);
Vector N = Normalize(Cross(dpdu, dpdv));
float e = Dot(N, d2Pduu);
float f = Dot(N, d2Pduv);
float g = Dot(N, d2Pdvv);
// Compute $\dndu$ and $\dndv$ from fundamental form coefficients
float invEGF2 = 1.f / (E*G - F*F);
Normal dndu = Normal((f*F - e*G) * invEGF2 * dpdu +
(e*F - f*E) * invEGF2 * dpdv);
Normal dndv = Normal((g*F - f*G) * invEGF2 * dpdu +
(f*F - g*E) * invEGF2 * dpdv);
//std::cout << "Got here?" << std::endl;
Matrix4x4 o2w_m;
o2w_m.m[0][3] = pos.x;
o2w_m.m[1][3] = pos.y;
o2w_m.m[2][3] = pos.z;
Transform o2w = Transform(o2w_m);
// Initialize _DifferentialGeometry_ from parametric information
*dg = DifferentialGeometry(o2w(phit), o2w(dpdu), o2w(dpdv),
o2w(dndu), o2w(dndv), u, v, parent);
dg->mult = 1.f;*/
// Update _tHit_ for quadric intersection
//*tHit = thit;
// Compute _rayEpsilon_ for quadric intersection
//*rayEpsilon = 5e-4f * *tHit;
return true;
}
