pavo (version 2.9.0)

hexagon: Colour hexagon

Description

Calculates coordinates and colourimetric variables that represent reflectance spectra in the hymenopteran colour hexagon.

Usage

hexagon(vismodeldata)

Value

A data frame of class colspace consisting of the following columns:

• s, m, l: the quantum catch data used to calculate the remaining variables

• x, y: cartesian coordinates in the colour hexagon.

• h.theta: hue angle theta (in degrees), with 0-degrees at the 1200 angle, increasing clockwise.

• r.vec: the r vector (saturation, distance from the center).

• sec.fine: fine 'hue sector', wherein the full hexagon is composed of 36 10-degree sectors, with 0-degrees at the 1200 angle.

• sec.coarse: coarse 'hue sector', wherein the full hexagon is composed of five sectors: blue, bluegreen, green, uvgreen, uv, and uvblue.

Arguments

vismodeldata

(required) quantum catch colour data. Can be either the result from vismodel() or independently calculated data (in the form of a data frame with three columns named 's', 'm', 'l', representing a trichromatic viewer).

Author

Thomas White

References

Chittka L. (1992). The colour hexagon: a chromaticity diagram based on photoreceptor excitations as a generalized representation of colour opponency. Journal of Comparative Physiology A, 170(5), 533-543.

Chittka L, Shmida A, Troje N, Menzel R. (1994). Ultraviolet as a component of flower reflections, and the colour perception of Hymenoptera. Vision research, 34(11), 1489-1508.

Examples

data(flowers)
vis.flowers <- vismodel(flowers,
  visual = "apis", qcatch = "Ei", relative = FALSE,
  vonkries = TRUE, achromatic = "l", bkg = "green"
)
flowers.hex <- colspace(vis.flowers, space = "hexagon")