paintOrbFrame function

void paintOrbFrame(Canvas canvas, OrbFrame frame, { required Color ink, required Color? background, required Offset offset, required Paint dotPaint, required Paint linePaint, })

Draws frame onto canvas: stroked lines first, then dots far → near.

Each dot is painted in ink, leaned toward its own tint when it has one, then faded by its ink and alpha channels — toward transparent, or toward background when that is given. offset shifts the whole frame; the two paints are reused across calls so nothing is allocated per dot.

Implementation

void paintOrbFrame(
  Canvas canvas,
  OrbFrame frame, {
  required Color ink,
  required Color? background,
  required Offset offset,
  required Paint dotPaint,
  required Paint linePaint,
}) {
  final dx = offset.dx;
  final dy = offset.dy;
  final order = frame.order;
  final data = frame.data;
  const stride = OrbFrame.stride;

  final lines = frame.lines;
  for (var i = 0; i < frame.lineCount; i++) {
    final b = i * OrbFrame.lineStride;
    linePaint
      ..color = _inkFor(ink, background, lines[b + 4], lines[b + 5])
      ..strokeWidth = lines[b + 6];
    canvas.drawLine(
      Offset(lines[b] + dx, lines[b + 1] + dy),
      Offset(lines[b + 2] + dx, lines[b + 3] + dy),
      linePaint,
    );
  }

  for (var k = 0; k < order.length; k++) {
    final base = order[k] * stride;
    final radius = data[base + 3];
    if (radius <= 0.01) {
      continue;
    }
    final tint = data[base + 9];
    final dotInk = tint <= 0
        ? ink
        : Color.lerp(
                ink,
                Color.from(
                  alpha: ink.a,
                  red: data[base + 6],
                  green: data[base + 7],
                  blue: data[base + 8],
                ),
                tint.clamp(0.0, 1.0),
              ) ??
              ink;
    dotPaint.color = _inkFor(
      dotInk,
      background,
      data[base + 4],
      data[base + 5],
    );
    canvas.drawCircle(
      Offset(data[base] + dx, data[base + 1] + dy),
      radius,
      dotPaint,
    );
  }
}