Modifying Local Origin

This example provides information on modifying the local coordinate position and orientation of a Part.

Before Local Origin Change

After Local Origin Change

Solution

1. Save the current GlobalMatrix of the Part.

   // Save the current global transformation matrix of the part 
   Matrix4 oldGlobalMatrix = part.Transform.GlobalMatrix;
   

2. Get the reference Transform of the part's parent, if it exists. This step ensures that transformations are relative to the parent coordinate system.

   // Get the parent's global transformation, if it exists  
   Transform refTrf = (part.Parent as IHasTransform)?.Transform;
   

3. Create a new identity matrix and apply the position and orientation arguments to it using Translation and EulerZYX. Then, update the part's global transformation matrix.

   // Create and set the new transformation matrix for the part
   Matrix4 mat = Matrix4.Identity;
   mat.Translation = position;
   mat.EulerZYX = orientation;
   part.Transform.GlobalMatrix = (refTrf == null) ? mat : (refTrf.GlobalMatrix * mat);
   

4. Calculate the transformation difference by comparing the new global matrix to the old one.

   // Calculate the transformation difference  
   Matrix4 newGlobalMatrix = part.Transform.GlobalMatrix;
   newGlobalMatrix.InvertRigid();
   Matrix4 diffTrans = newGlobalMatrix * oldGlobalMatrix;
   

5. Move all bodies back to their original positions using the transformation difference. If the part has geometry, apply the transformation to each body. Otherwise, apply it to the entire mesh.

   // Move all the bodies back to the original position
   if (part.HasGeometry)
   {
       foreach (Body bd in part.Bodies)
       {
           bd.Transform.Matrix = diffTrans * bd.Transform.Matrix;
       }
   }
   else
   {
       part.Mesh.Transform(diffTrans);
       part.Mesh.Rebuild();
   }
   

Example

This function returns typesafe collection of all the Part objects in station.

private static List<Part> GetStationParts()
{
    var parts = new List<Part>();
    foreach (var component in Station.ActiveStation.GraphicComponents)
    {
        if (component is Part part)
        {
            parts.Add(part);
        }
    }
    return parts;
}

This is an example of how the local origin can be modified.

private static void ApplyLocalChange(Part part, Vector3 position, Vector3 orientation)
{
    Project.UndoContext.BeginUndoStep();
    try
    {
        if (part != null)
        {
            // Save the current global transformation matrix of the part 
            Matrix4 oldGlobalMatrix = part.Transform.GlobalMatrix;

            // Get the parent's global transformation, if it exists  
            Transform refTrf = (part.Parent as IHasTransform)?.Transform;

            // Create and set the new transformation matrix for the part
            Matrix4 mat = Matrix4.Identity;
            mat.Translation = position;
            mat.EulerZYX = orientation;
            part.Transform.GlobalMatrix = (refTrf == null) ? mat : (refTrf.GlobalMatrix * mat);

            // Calculate the transformation difference  
            Matrix4 newGlobalMatrix = part.Transform.GlobalMatrix;
            newGlobalMatrix.InvertRigid();
            Matrix4 diffTrans = newGlobalMatrix * oldGlobalMatrix;

            // Move all the bodies back to the original position
            if (part.HasGeometry)
            {
                foreach (Body bd in part.Bodies)
                {
                    bd.Transform.Matrix = diffTrans * bd.Transform.Matrix;
                }
            }
            else
            {
                part.Mesh.Transform(diffTrans);
                part.Mesh.Rebuild();
            }
        }
    }
    catch
    {
        Project.UndoContext.CancelUndoStep(CancelUndoStepType.Rollback);
        throw;
    }
    finally
    {
        Project.UndoContext.EndUndoStep();
    }
}

This is an example of how ApplyLocalChange can be used:

// Get all CAD parts from station
List<Part> partList = GetStationParts();

// Set new position
Vector3 position = new Vector3(2.0, 2.0, 2.0);

// Set new orientation
Vector3 orientation = new Vector3(Globals.DegToRad(90), Globals.DegToRad(30), Globals.DegToRad(30));

// Adjust local origin
foreach (Part part in partList)
{
    ApplyLocalChange(part, position, orientation);
}

Required Namespaces

ABB.Robotics.RobotStudio

ABB.Robotics.RobotStudio.Stations

ABB.Robotics.Math

See Also

• Modify Position