Rainbow constructor

Rainbow({
  1. List<String> spectrum = const ['000000', 'ffffff'],
  2. dynamic rangeStart = 0.0,
  3. dynamic rangeEnd = 1.0,
})

Construct a new Rainbow

@param spectrum The list of color stops in the transitioning color range. @param rangeStart The beginning of the numerical domain to map. @param rangeEnd The end of the numerical domain to map.

Implementation

Rainbow(
    {List<String> spectrum = const ['000000', 'ffffff'],
    rangeStart = 0.0,
    rangeEnd = 1.0})
    : _gradients = _spectrumToGradients(spectrum, rangeStart, rangeEnd),
      _rangeStart = rangeStart,
      _rangeEnd = rangeEnd,
      _includeOpacity = _spectrumContainsOpacity(spectrum) {
  assert(spectrum.length >= 2);
  assert(rangeStart != rangeEnd);
  assert(rangeStart != null && rangeEnd != null);
}