Lens API

Forward raytrace.

• double Lens::psiXvalue( double x, double y ) const

• double Lens::psiYvalue( double x, double y ) const

Inverse raytrace

• cv::Point2d Lens::getXi( cv::Point2d chieta ) returns the apparent position $\xi$ corresponding to actual position $\chi\eta$ (chieta). This is primarily used to find the reference point for the roulette formalism.

  • Co-ordinates are in the lens plane to be totally independent of the source.

  • See calculation

Lens potential

• double Lens::psiValue( double x, double y ) const is used primarily for sampling to create SampledLens models from PsiFunctionLens models.

Roulette formalism

• void Lens::calculateAlphaBeta( cv::Point2d xi, int m ) calculates the roulette amplitudes in the given point xi up the given order m

• double Lens::getAlphaXi( int m, int s )

• double Lens::getBetaXi( int m, int s )

• double Lens::getAlpha( cv::Point2d xi, int m, int s )

• double Lens::getBeta( cv::Point2d xi, int m, int s )

Debugging and diagnostics

• std::string Lens::idString() returns a string to identify the lens model. This is intended for use in debugging output

Caustics and Critical Curves (under construction)

• double Lens::criticalXi( double phi ) const

• cv::Point2d Lens::caustic( double phi ) const