Radial Spectral Mandala — hsa_mandala • hyperspectaculR

Renders the scene as concentric annuli, each drawn from a different wavelength: the innermost ring shows the shortest wavelength, the outermost the longest. The result is a single image that sweeps the spectral axis outward from a chosen centre.

Usage

hsa_mandala(
  cube,
  centre = NULL,
  n_rings = 36L,
  palette = "magma",
  stretch = c("percentile", "range", "none"),
  probs = c(0.02, 0.98)
)

Arguments

cube: An hsi_cube (from hyperspectR) or a 3-D array with dimensions (rows, cols, bands).
centre: Numeric length-2 vector c(x, y) in pixels. NULL (default) uses the image centre.
n_rings: Number of annuli. Default 36. More rings sample the spectrum more finely; fewer give bolder banding.
palette: Palette name passed to hsa_palette().
stretch: Contrast stretch: "percentile" (default), "range" or "none".
probs: Percentiles for stretch = "percentile". Default c(0.02, 0.98).

Value

A ggplot2 object.

Details

This exploits the spectral dimension rather than decorating a single band, which is what distinguishes it from an ordinary false-colour rendering. The radius-to-wavelength mapping is linear and reported in the caption, so the figure remains readable as data.

Examples

cube <- hsa_demo_cube()
hsa_mandala(cube, n_rings = 12)