Calculates coordinates and colorimetric variables that represent reflectance spectra
in the avian tetrahedral color space.
Usage
tcspace(vismodeldata)
Arguments
vismodeldata
(required) quantum catch color data. Can be either the result
from vismodel or independently calculated data (in the form of a data frame
with four columns, representing the avian cones).
Value
A data frame of class tcs consisting of the following columns:u, s, m, l: the quantum catch data used to
calculate the remaining variables. NOTE: even if visual sistem is of type V-VIS,
the output column will be labeled u.u.r, s.r, m.r, l.r: relative cone stimulation,
for a given hue, as a function of saturation. See Stoddard & Prum (2008) for details.x, y, z: cartesian coordinates for the points in the
tetrahedral color space.h.theta, h.phi: angles theta and phi, in radians, determining
the hue of the color.r.vec: the r vector (saturation, distance from the achromatic center).r.max: the maximum r vector achievable for the color's hue.r.achieved: the relative r distance from the achromatic center, in
relation to the maximum distance achievable (r.vec/r.max).
References
Stoddard, M. C., & Prum, R. O. (2008). Evolution of avian plumage
color in a tetrahedral color space: A phylogenetic analysis of new world buntings.
The American Naturalist, 171(6), 755-776.
Endler, J. A., & Mielke, P. (2005). Comparing entire colour patterns
as birds see them. Biological Journal Of The Linnean Society, 86(4), 405-431.