public override double get_refractive_index(double wavelen)
{
if (wavelen == _last_wavelen)
{
return(_last_get_refractive_index);
}
double a = _measurement_medium.get_refractive_index(wavelen);
double m = get_measurement_index(wavelen);
// get absolute refractive index
double n = m * a;
// apply temperature coefficients
switch (_temp_model)
{
case thermal_model_e.ThermalSchott:
n = n + get_schott_temp(wavelen, m);
break;
case thermal_model_e.ThermalDnDt: {
double dt = _temperature - _measurement_medium.get_temperature();
n = n + dt * _temp_d0;
break;
}
case thermal_model_e.ThermalNone:
break;
}
_last_wavelen = wavelen;
_last_get_refractive_index = n;
return(n);
}
/** Get transmittance at normal incidence */
public virtual double get_normal_transmittance(Medium from,
double wavelen)
{
// default transmittance at normal incidence, valid for non absorbing material
// McGraw Hill, Handbook of optics, vol1, 1995, 5-8 (23)
double n0 = from.get_refractive_index(wavelen);
double n1 = get_refractive_index(wavelen);
return((4.0 * n0 * n1) / MathUtils.square(n0 + n1));
}
/** Get reflectance at normal incidence */
public virtual double get_normal_reflectance(Medium from,
double wavelen)
{
// default reflectance at normal incidence, valid for metal and dielectric
// material
// McGraw Hill, Handbook of optics, vol1, 1995, 5-10 (47)
double n0 = from.get_refractive_index(wavelen);
double k12 = MathUtils.square(get_extinction_coef(wavelen));
double n1 = get_refractive_index(wavelen);
double res = (MathUtils.square(n0 - n1) + k12) / (MathUtils.square(n0 + n1) + k12);
return(res);
}
private TracedRay trace_ray_simple(OpticalSurface surface, RayTraceResults result, TracedRay incident,
Vector3Pair local, Vector3Pair intersect)
{
bool right_to_left = intersect.normal().z() > 0;
Medium prev_mat = surface.get_material(right_to_left ? 1 : 0);
Medium next_mat = surface.get_material(!right_to_left ? 1 : 0);
// check ray didn't "escaped" from its material
// std::cout << prev_mat->name << " " << next_mat->name <<
// " " << incident.get_material()->name << std::endl;
if (prev_mat != incident.get_material())
{
return(null);
}
double wl = incident.get_wavelen();
double index = prev_mat.get_refractive_index(wl)
/ next_mat.get_refractive_index(wl);
// refracted ray direction
Vector3 direction = refract(surface, local, intersect.normal(), index);
if (direction == null)
{
// total internal reflection
Vector3 o = intersect.origin();
Vector3 dir = reflect(surface, local, intersect.normal());
TracedRay r = result.newRay(o, dir);
r.set_wavelen(wl);
r.set_intensity(incident.get_intensity());
r.set_material(prev_mat);
r.set_creator(surface);
incident.add_generated(r);
return(r);
}
// transmit
if (!next_mat.is_opaque())
{
Vector3 o = intersect.origin();
TracedRay r = result.newRay(o, direction);
r.set_wavelen(wl);
r.set_intensity(incident.get_intensity());
r.set_material(next_mat);
r.set_creator(surface);
incident.add_generated(r);
return(r);
}
// reflect
if (next_mat.is_reflecting())
{
Vector3 o = intersect.origin();
Vector3 dir = reflect(surface, local, intersect.normal());
TracedRay r = result.newRay(o, dir);
r.set_wavelen(wl);
r.set_intensity(incident.get_intensity());
r.set_material(prev_mat);
r.set_creator(surface);
incident.add_generated(r);
return(r);
}
return(null);
}
/** Get material relative refractive index in given medium at specified
* wavelen in @em nm. */
public virtual double get_refractive_index(double wavelen, Medium env)
{
return(get_refractive_index(wavelen) / env.get_refractive_index(wavelen));
}
