The 11-stop palettes the app must draw with

The legend, the popup swatch and the choropleth bins have to equal what R drew and what titiler rendered, so the ramps are shipped rather than re-derived by a JavaScript colour library interpolating in a different space.

Usage

app_palettes(names = c("spectral_r", "viridis", "cividis", "magma"))

Arguments

names

colormap names to build (default: the four the contract lists)

Value

a named list of 11 upper-case #RRGGBB strings each

Details

spectral_r is ColorBrewer Spectral reversed, interpolated in Lab (colorRampPalette(space = "Lab")), which is what msens::viz uses. The perceptual ramps come from viridisLite, whose values are matplotlib's own — the same table titiler renders from. grDevices::hcl.colors() is deliberately not used: it re-derives them in HCL and, on some builds, errors outright on Cividis.

Unknown names are an error, never a silent substitution: a layer rendered in the wrong ramp is a legend that lies.