edgesOf static method

Uint32List edgesOf(List<int> indices)

The unique edges of the triangles in indices, as index pairs.

Implementation

static Uint32List edgesOf(List<int> indices) {
  final seen = <int>{};
  final out = <int>[];
  for (var t = 0; t + 2 < indices.length; t += 3) {
    for (var k = 0; k < 3; k++) {
      final a = indices[t + k], b = indices[t + (k + 1) % 3];
      final lo = a < b ? a : b, hi = a < b ? b : a;
      if (seen.add(lo * 0x100000000 + hi)) {
        out
          ..add(lo)
          ..add(hi);
      }
    }
  }
  return Uint32List.fromList(out);
}