opacity method

ColorFilterGenerator opacity(double value)

Create new filter from this filter with given opacity

Implementation

ColorFilterGenerator opacity(double value) {
  return ColorFilterGenerator(name: name, filters: [
    ...filters,
    [
      value,
      0,
      0,
      0,
      0,
      0,
      value,
      0,
      0,
      0,
      0,
      0,
      value,
      0,
      0,
      0,
      0,
      0,
      1,
      0,
    ],
  ]);
}