Posts: 19
Registered: ‎06-21-2012
Message 1 of 3 (380 Views)
Accepted Solution

Geometric constraints

380 Views, 2 Replies
11-16-2012 02:38 PM

In a given drawing I want to list pairs of blocks that are constrained to each other by "coincidence constraint" .

For example, I have a simple drawing with a rectangle block and a line block . I applied coincidence constraint to the end of the line and midpoint of one edge of the rectangle block

I get the Assoc2dConstraintGroup  object for the drawing  and I can see the constraints array for this object in the watch window. It has one midpoint constraint , one point coincidence constraint and 5 point curve constraints. I think I need to explore the point coincidence constraint, but I am not sure. How can I extract the information I am looking for? I see variables like connected geometries and connected constraints but I am not able to tie them together to derive what I want.
 also Is there a MSDN/ javadocs style API browser for AutoCAD. net? that would be a HUGE help..


ADN Support Specialist
Posts: 616
Registered: ‎06-02-2009
Message 2 of 3 (297 Views)

Re: Geometric constraints

12-04-2012 01:17 AM in reply to: insiaiftiqhar

Hi There,


You can refer to the following post that illustrates how to iterate through the constraints:




Once you have access to a GeometricalConstraint object, you can use its "ConnectedGeometries" property to deduce on which entity is applied the constraint:


void DumpConstrainedGeometry(
    Transaction Tx, 
    ConstrainedGeometry[] geometries)
    Document doc = Application.DocumentManager.MdiActiveDocument;
    Editor ed = doc.Editor;

    foreach (ConstrainedGeometry goemetry in geometries)
        ed.WriteMessage("\n  - Constrained Geometry: " + 
            goemetry.ToString().Remove(0, 34));

        if(goemetry.GeomDependencyId != ObjectId.Null)
            AssocGeomDependency goemDep = Tx.GetObject(
                    as AssocGeomDependency;

            Entity entity = Tx.GetObject(
                    as Entity;

            ed.WriteMessage(" with Constrained Entity: " + 
                entity.ToString().Remove(0, 34));


        DumpConstrainedGeometry(Tx, goemetry.ConnectedGeometries);


Concerning the doc question, there is a chm help file coming with the ObjectARX SDK that is quite helpful.




Philippe Leefsma
Developer Technical Services
Autodesk Developer Network

Posts: 19
Registered: ‎06-21-2012
Message 3 of 3 (285 Views)

Re: Geometric constraints

12-04-2012 12:35 PM in reply to: philippe.leefsma

Thank you Thank you Thank you!

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