How to retrieve a Dimension's (segment) geometry ?

[maisoui]

Hello,

I'd like to retrieve the geometry of a Dimension : for each Dimension's segment, I'd like to have start, end points and text position and direction. I'm able to obtain the text position and the text string by looping on segments array :

foreach(DimensionSegment segment in dimension.Segments)
{
   //segment.TextPosition
   //segment.ValueString
}

But, I don't understand how to obtain the segment's points and direction. I tried get_geometry and looping on references array, but no success.

foreach(Reference reference in dimension.References)
{
    reference.GlobalPoint; // ---> always null
}

I don't find any samples.

Any suggestion is welcomed.

Best regards,

[jeremytammik]

Not quite... with the current code, plus an additional method DrawMarker to add model lines marking the 'start point and the three 'further points', I currently get the following result:

[FAIR59]

as you can see, is the first Mark positioned on the MidPoint of the first segment.
We still have to adjust the GetDimensionStartPoint() method: 


XYZ p = null;
double length=0;
XYZ direction =(dim.Curve as Line).Direction.Normalize();
      try
      {
        p = dim.Origin;
        length = dim.Value;
      }
      catch( Autodesk.Revit.Exceptions.ApplicationException ex )
      {
        Debug.Assert( ex.Message.Equals( "Cannot access this method if this dimension has more than one segment." ) );

        foreach( DimensionSegment seg in dim.Segments )
        {
          p = seg.Origin;
          length = seg.Value;
          break;
        }
      }
      return p.Subtract(direction.Multiply(length/2));

[jeremytammik]

Yes indeed. It works now:

[jeremytammik]

I summarised the results on The Building Coder for future reference:

http://thebuildingcoder.typepad.com/blog/2017/06/determining-dimension-segment-endoints.html

Thank you very much, Fair59, for all your advice and support!

Cheers,

Jeremy

[maisoui]

Sorry for the delay. Here's my final code:

private List<DimensionInfo> dumpDimension(Dimension dimension)
{
	Curve curve = dimension.Curve;
	Line line = curve as Line;
	XYZ point1 = null;
	XYZ point2 = null;
	XYZ direction = null;

	IntersectionResult projection = null;
	XYZ ortho = null;

	BcGeCurve geCurve = null;
	if(line != null)
	{
		if(line.IsBound)
		{
			point1 = line.GetEndPoint(0);
			direction = line.Direction;
			geCurve = createLine(point1, direction, false, Transform.Identity);
		}
		else
		{
			point1 = line.Origin;
			direction = line.Direction;
			geCurve = createLine(point1, direction, true, Transform.Identity);
		}
	}
	else
	{
		geCurve = createCurve(curve.Tessellate(), Transform.Identity);
	}

	//dump dimension (segments) info
	List<DimensionInfo> dimensionInfos = new List<DimensionInfo>();
	if(dimension.Segments.Size == 0)
	{
		projection = line.Project(dimension.LeaderEndPosition);
		ortho = dimension.LeaderEndPosition.Subtract(projection.XYZPoint);
		//TODO: find the correct leader point

		point1 = dimension.Origin.Subtract(direction.Multiply((double)dimension.Value / 2.0));
		point2 = point1.Add(direction.Multiply((double)dimension.Value));
		DimensionInfo dimensionInfo = new DimensionInfo(point1.Add(ortho), point2.Add(ortho), point1, dimension.TextPosition, dimension.ValueString)
		dimensionInfos.Add(dimensionInfo);
	}
	else
	{
		foreach(DimensionSegment segment in dimension.Segments)
		{
			projection = line.Project(segment.LeaderEndPosition);
			ortho = segment.LeaderEndPosition.Subtract(projection.XYZPoint);
			//TODO: find the correct leader point

			point1 = segment.Origin.Subtract(direction.Multiply((double)segment.Value / 2.0));
			point2 = point1.Add(direction.Multiply((double)segment.Value));
			DimensionInfo dimensionInfo = new DimensionInfo(point1.Add(ortho), point2.Add(ortho), point1, segment.TextPosition, segment.ValueString)
		dimensionInfos.Add(dimensionInfo);
		}
	}

	return dimensionInfos;
}

The "xlinePoint1" and "xlinePoint2" is not correct yet.

I'm looking forward for a solution.

[Anonymous]

Hi @jeremytammik ,

I'm facing the same issue as this thread's title. I'm getting an unbound line from my dimension and can't get the curve from it, do you know if the engineering team has already got a solution for this?

I tried the solution mentioned in this topic, but it is not completely clear to me as there are some variable definitions that are not given in the context.

Any tip of advice will be very well received.

Regards!

[mehdi.blanchard]

The Origin being the middle of the dimension I had to actually substract half the length to get the correct first point Pt1:

pt1 = pt1.Add(-direction.Multiply((double)dim.Value/2));

[mehdi.blanchard]

The Origin being the middle of the dimension, I had to substract half the length to get the correct start point Pt1:

pt1 = pt1.Add(-direction.Multiply((double)dim.Value/2));

[Simon.Pusateri]

Cheers from 5 years later! dim.curve still gives an unbound curve, but this thread has been a bit of a lifesaver!

[jeremy_tammik]

Glad to hear you found it useful. 🙂