CTTKhexagon             Chittka (1992) colour hexagon
CTTKhexagon3D           Chittka (1992) colour space for tetrachromatic
                        animals.
CTTKmodel               Chittka (1992) colour vision models
D65                     CIE Standard Illuminant D65 in quantum flux
                        (umol/m2/s)
EMmodel                 Endler and Mielke (2005) colour vision model
EMtetrahedron           Endler and Mielke (2005) tetrahedron colour
                        space
EMtriangle              Endler and Mielke (2005) triangle colour space
Q                       Total photon capture
Qr                      Photoreceptor relative quantum catch
RNLmodel                Receptor Noise Limited Models (Vorobyev &
                        Osorio 1998)
RNLthres                Colour thresholds based on the Receptor Noise
                        Limited Model (Vorobyev & Osorio 1998).
Rb                      Brazilian savannah background reflectance
                        spectrum.
bee                     Honeybee photoreceptors
colour_space            N-dimensional colour spaces
colourvision-package    Colour Vision Models
energytoflux            Irradiance from energy to quantum units.
logistic                Logistic curve
noise_e                 Receptor noise
photor                  Photoreceptor sensitivity spectra.
plot.colourvision       Plot colour vision models into chromaticity
                        diagrams
plot3d.colourvision     Plot colour vision models into 3D chromaticity
                        diagrams.
spec.denoise            Smooth function for reflectance spectra.
