Const
Derives the map colours from an image — a photo, a logo, a poster — by extracting its dominant colours and assigning them roles with deriveMapColors.
Optional
RangeError when the image has no opaque pixels, or an error when it cannot be read (not CORS-readable, no DOM to decode it).
RangeError
Derives the map colours from an image — a photo, a logo, a poster — by extracting its dominant colours and assigning them roles with deriveMapColors.