/// <summary>
/// 自动计算指定端点的相对位置。
/// </summary>
private void AutoResetRelativePos()
{
if (_autoPositionPoints == AutoPositionPoints.None)
{
return;
}
var from = Source.GetRect();
var to = Sink.GetRect();
if ((_autoPositionPoints & AutoPositionPoints.Source) != 0)
{
var toCenter = to.GetCenterPoint();
if (!from.Contains(toCenter))
{
var point = RectAlgorithm.CalcCrossPoint(from, toCenter);
this._sourceRelativePos = RectAlgorithm.GetRectRelative(from, point);
}
}
if ((_autoPositionPoints & AutoPositionPoints.Sink) != 0)
{
var fromCenter = from.GetCenterPoint();
if (!to.Contains(fromCenter))
{
var point = RectAlgorithm.CalcCrossPoint(to, fromCenter);
this._sinkRelativePos = RectAlgorithm.GetRectRelative(to, point);
}
}
}
void thumbDragThumb_DragDelta(object sender, DragDeltaEventArgs e)
{
Point mouse = Mouse.GetPosition(this);
if (!_changeTarget)
{
//拖拽的量比较大，则进入变更目标模式
if (_designerCanvas.CanChangeConnection && LeftDraggingItem(mouse))
{
_changeTarget = true;
_rawStrokeDashArray = _connection.StrokeDashArray;
this._connection.StrokeDashArray = ChangeTargetLineStrokeDashArray;
}
}
if (!_changeTarget)
{
//小幅度在元素的边上移动
var rect = _draggingItem.GetRect();
var point = RectAlgorithm.NearestPointOnLine(rect, mouse);
var relative = RectAlgorithm.GetRectRelative(rect, point);
if (_connection.Source == _draggingItem)
{
_connection.SourceRelativePos = relative;
}
else
{
_connection.SinkRelativePos = relative;
}
}
else
{
this.HitTesting(mouse);
//变换目标时，需要绘制一根临时的连接连
var start = _connection.Source == _startItem ? _connection.SourceConnectorInfo : _connection.SinkConnectorInfo;
this._pathGeometry = PathHelper.DarwGeometry(start, mouse);
}
this.InvalidateVisual();
}
