Photon::Photon(const Point &p, const Normal &normal,
const Vector &dir, const Spectrum &P,
uint16_t _depth) {
if (!P.isValid())
SLog(EWarn, "Creating an invalid photon with power: %s", P.toString().c_str());
/* Possibly convert to single precision floating point
(if Mitsuba is configured to use double precision) */
position = p;
data.depth = _depth;
flags = 0;
/* Convert the direction into an approximate spherical
coordinate format to reduce storage requirements */
data.theta = (uint8_t) std::min(255,
(int) (math::safe_acos(dir.z) * (256.0 / M_PI)));
int tmp = std::min(255,
(int) (std::atan2(dir.y, dir.x) * (256.0 / (2.0 * M_PI))));
if (tmp < 0)
data.phi = (uint8_t) (tmp + 256);
else
data.phi = (uint8_t) tmp;
if (normal.isZero()) {
data.thetaN = data.phiN = 0;
} else {
data.thetaN = (uint8_t) std::min(255,
(int) (math::safe_acos(normal.z) * (256.0 / M_PI)));
tmp = std::min(255,
(int) (std::atan2(normal.y, normal.x) * (256.0 / (2.0 * M_PI))));
if (tmp < 0)
data.phiN = (uint8_t) (tmp + 256);
else
data.phiN = (uint8_t) tmp;
}
#if defined(SINGLE_PRECISION) && SPECTRUM_SAMPLES == 3
/* Pack the photon power into Greg Ward's RGBE format */
P.toRGBE(data.power);
#else
data.power = P;
#endif
}
