inline Spectrum Le(const Vector &direction) const {
/* Compute sky light radiance for direction */
Vector d = normalize(m_worldToLuminaire(direction));
if (m_clipBelowHorizon) {
/* if sun is below horizon, return black */
if (d.z < 0.0f)
return Spectrum(0.0f);
}
/* make all "zero values" the same */
if (d.z < 0.001f)
d = normalize(Vector(d.x, d.y, 0.001f));
const Point2 dSpherical = toSphericalCoordinates(d);
const Float theta = dSpherical.x;
#ifndef ENFORCE_SINGLE_ZENITH_ANGLE
const Float phi = dSpherical.y;
#else
Float phi;
if (fabs(theta) < 1e-5)
phi = 0.0f;
else
phi = dSpherical.y;
#endif
Spectrum L;
getSkySpectralRadiance(theta, phi, L);
L *= m_skyScale;
return L;
}
void test04_sphere() {
Properties props("sphere");
Float radius = 2.0f;
props.setFloat("radius", radius);
props.setPoint("center", Point(0.0f));
ref<Shape> sphere = static_cast<Shape *>(PluginManager::getInstance()->createObject(props));
sphere->configure();
ref<ShapeKDTree> kdtree = new ShapeKDTree();
kdtree->addShape(sphere);
kdtree->build();
Ray ray(Point(3, 3, 3), normalize(Vector(-1, -1, -1)), 123.0f);
Intersection its;
assertTrue(kdtree->rayIntersect(ray, its));
assertEquals(its.time, 123.0f);
assertEqualsEpsilon(its.p, Point(ray.d*-2.0f), Epsilon);
assertEqualsEpsilon(its.wi, Vector(0, 0, 1), Epsilon);
assertEqualsEpsilon(its.shFrame.n, -ray.d, Epsilon);
assertTrue(its.shFrame == its.geoFrame);
Point2 sc = toSphericalCoordinates(Vector(its.p));
std::swap(sc.x, sc.y);
sc.x *= INV_TWOPI;
sc.y *= INV_PI;
assertEqualsEpsilon(its.uv, sc, Epsilon);
// from mathematica
assertEqualsEpsilon(its.dpdu, Vector(-3.6276f, 3.6276f, 0.0f)*radius, 1e-4f);
assertEqualsEpsilon(its.dpdv, Vector(1.28255f, 1.28255f, -2.5651f)*radius, 1e-4f);
Vector dndu, dndv;
its.shape->getNormalDerivative(its, dndu, dndv, false);
assertEqualsEpsilon(dndu, Vector(-3.6276f, 3.6276f, 0.0f), 1e-4f);
assertEqualsEpsilon(dndv, Vector(1.28255f, 1.28255f, -2.5651f), 1e-4f);
Float H, K;
its.shape->getCurvature(its, H, K);
assertEquals(K, 1.0f / (radius*radius));
assertEquals(H, -1.0f / radius);
}
/**
* Configures the position of the sun by using a vector that points
* to the sun. It is expected, that +x = south, +y = east, +z = up.
*/
void configureSunPosition(const Vector& sunDir) {
Vector wh = normalize(sunDir);
Point2 sunPos = toSphericalCoordinates(wh);
m_thetaS = sunPos.x;
m_phiS = sunPos.y;
}
