deltaEOK function

double deltaEOK(
  1. Lab x,
  2. Lab y
)

Euclidean distance in OKLab (ΔEOK; 0.02 ≈ one JND).

Implementation

double deltaEOK(Lab x, Lab y) {
  final dl = x.$1 - y.$1;
  final da = x.$2 - y.$2;
  final db = x.$3 - y.$3;
  return detSqrt(dl * dl + da * da + db * db);
}