R/Wulffnet.R

In GrimR: Calculate Optical Parameters from Spindle Stage Measurements

#' Function Wulffnet
Wulffnet <-
function (add = FALSE, col = gray(0.7), border = "black", lwd = 1) 
{
    if (missing(add)) {
        add = FALSE
    }
    if (missing(col)) {
        col = gray(0.7)
    }
    if (missing(lwd)) {
        lwd = 1
    }
    if (missing(border)) {
        border = "black"
    }
    if (add == FALSE) {
        plot(c(-1, 1), c(-1, 1), type = "n", ylab = "", xlab = "", 
            asp = 1, axes = FALSE, ann = FALSE)
    }

    pcirc(gcol = col, border = border, ndiv = 72)
    lam = pi * seq(from = 0, to = 180, by = 5)/180
    lam0 = pi/2
    for (j in seq(from = -80, to = 80, by = 10)) {
        phi = j * pi/180
        R = 1/2
        k = 2/(1 + cos(phi) * cos(lam - lam0))
        y = R * k * cos(phi) * sin(lam - lam0)
        x = R * k * sin(phi)
        lines(x, y, col = col, lwd = lwd)
    }
    phi = seq(from = -90, to = 90, by = 5) * pi/180
    for (j in seq(from = 10, to = 170, by = 10)) {
        lam = j * pi/180
        R = 1/2
        k = 2/(1 + cos(phi) * cos(lam - lam0))
        y = R * k * cos(phi) * sin(lam - lam0)
        x = R * k * sin(phi)
        lines(x, y, col = col, lwd = lwd)
    }
    segments(c(-0.02, 0), c(0, -0.02), c(0.02, 0), c(0, 0.02), 
        col = "black")
}