Stellarium 0.11.2
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Public Member Functions
Extinction Class Reference

This class performs extinction computations, following literature from atmospheric optics and astronomy. More...

#include <RefractionExtinction.hpp>

List of all members.

Public Member Functions

void forward (const Vec3d *altAzPos, float *mag, const int num=1) const
void forward (const Vec3f *altAzPos, float *mag, const int num=1) const
void forward (const double *sinAlt, float *mag, const int num) const
void forward (const float *sinAlt, float *mag, const int num) const
void forward (const double *sinAlt, float *mag) const
void forward (const float *sinAlt, float *mag) const
void backward (const Vec3d *altAzPos, float *mag, const int num=1) const
void backward (const Vec3f *altAzPos, float *mag, const int num=1) const
void backward (const double *sinAlt, float *mag, const int num=1) const
void backward (const float *sinAlt, float *mag, const int num=1) const
void setExtinctionCoefficient (float k)
float getExtinctionCoefficient () const

Detailed Description

This class performs extinction computations, following literature from atmospheric optics and astronomy.

Airmass computations are limited to meaningful altitudes. The solution provided here will [hopefully!] result in a visible "zone of avoidance" near the horizon down to altitude -2, and may show stars in their full brightness below -2 degrees. Typical horizons do not go down below -1, so all natural sites should be covered. Note that forward/backward are no absolute reverse operations! All the computations should be in effect (1) only if atmosphere effects are true (2) only for terrestrial locations, not on Moon/Mars/Saturn etc config.ini:astro/flag_extinction_below_horizon=true|false controls if extinction kills objects below -2 degrees altitude by setting airmass to 42.


Member Function Documentation

void Extinction::backward ( const Vec3d altAzPos,
float *  mag,
const int  num = 1 
) const

Compute inverse extinction effect for arrays of size.

Parameters:
numposition vectors and magnitudes.
altAzPosare the NORMALIZED (!!) (apparent) star position vectors, and their z components sin(apparent_altitude). Note that forward/backward are no absolute reverse operations!
void Extinction::forward ( const Vec3d altAzPos,
float *  mag,
const int  num = 1 
) const

Compute extinction effect for arrays of size.

Parameters:
numposition vectors and magnitudes.
altAzPosare the NORMALIZED (!!) (apparent) star position vectors, and their z components sin(apparent_altitude). This call must therefore be done after application of Refraction, and only if atmospheric effects are on. Note that forward/backward are no absolute reverse operations!
void Extinction::setExtinctionCoefficient ( float  k) [inline]

Set visual extinction coefficient (mag/airmass), influences extinction computation.

Parameters:
k=0.1 for highest mountains, 0.2 for very good lowland locations, 0.35 for typical lowland, 0.5 in humid climates.