Hi there,

Welcome to our humble forum ;)

The ValidateAnchor event won't help you with that. It is raised for each anchor point of a node to let you filter the possible points to which an arrow can connect. From the validated points, the one closest to the arrow end point is used. So at the moment when ValidateAnchor is raised, it is not yet known which point will be used as a destination.

If you don't filter out any anchor points, you can safely assume the arrow would connect to the one closest to its end point. The type of the anchor point, incoming or outgoing, should match the end of the arrow is being moved too. The Node class uses this code to select the anchor point (the rotation stuff is skipped):

[code]
for (int i = 0; i < anchorPattern.Points.Count; i++)
{
  AnchorPoint ap = anchorPattern.Points[i];
  if (incoming && !ap.AllowIncoming) continue;
  if (!incoming && !ap.AllowOutgoing) continue;
  if (!fcParent.validateAnchor(arrow, !incoming, this, i)) continue;

  PointF pos = ap.getPos(nodeRect);
  float dx = pos.X - pt.X;
  float dy = pos.Y - pt.Y;
  float ptDist = (float)Math.Sqrt(dx*dx + dy*dy);
  if (ptDist < nearestDist)
  {
    nearestDist = ptDist;
    nearestPt = pos;
    anchorIdx = i;
  }
}

return nearestPt;
[/code]

The getPos method looks like

internal PointF getPos(RectangleF nodeRect)
{
  return new PointF(
    nodeRect.X + nodeRect.Width * x / 100,
    nodeRect.Y + nodeRect.Height * y / 100);
}

The 'nearestPt' and 'anchorIdx' found above will let you know to which point the arrow would connect. If you have troubles with that code, we can make the Node method that contains it public, so you can use the FC.NET implementation.

I hope that helps,
Stoyan

Hi,

1) if that's some code dependent on the mouse position, you could handle the MouseMove event instead of using a timer.

2) That's a good guess Usually display settings use a 96 pixels per inch resolution, and an inch has 25.4 millimeters, so 1mm would have 96/25.4 pixels. The MS Calculator gives 3.7795275590551181102362204724409 as a result.

Better use the ClientToDoc method to convert pixel coordinates to logical ones. ClientToDoc uses the "Graphics.TransformPoints" method, which uses the DPI value set in the display adapter settings page.

Stoyan