Construction Point and Selection of circular face of extruded body

[julia.bergVCCN8]

Hi everyone, I am getting a little desperate. 

I have a script, which creates an extruded body based on a circular sketch on a selected plane. That works so far. After that, I want to make a construction point in the center at the top face of my extrusion and select this face for later, in order to align it to another circular face.

My problem is, that I always get the following error when trying to construct the point:

...line 110, in createdockingObject

center_point = constructionPoints.add(pointInput)

File "C:\Users/julia/AppData/Local/Autodesk/webdeploy/production/19107935ce2ad08720646cb4a31efe37d8a5f41b/Api/Python/packages\adsk\fusion.py", line 13404, in add

return _fusion.ConstructionPoints_add(self, input)

RuntimeError: 2 : InternalValidationError : data_->execute(&obj, apiName) && obj

It works, when I use the sketch circle. And I tried it with the circular face, using the startFace Property of the extrusion, the circular edge. It doesn't work...

Then I also try to use the  ui.activeSelections.add command to select the circular face or the edge to use it. In this case, I get the following error:

...line 118, in createdockingObject
ui.activeSelections.add(circularFace)
File "C:\Users/julia/AppData/Local/Autodesk/webdeploy/production/19107935ce2ad08720646cb4a31efe37d8a5f41b/Api/Python/packages\adsk\core.py", line 14956, in add
return _core.Selections_add(self, entity)
RuntimeError: 3 : invalid argument entity

Here is the main code part. I also upload the whole script.

def createNewComponent():
    # Get the active design.
    product = app.activeProduct
    design = adsk.fusion.Design.cast(product)
    rootComp = design.rootComponent
    allOccs = rootComp.occurrences
    newOcc = allOccs.addNewComponent(adsk.core.Matrix3D.create())
    return newOcc.component

def createdockingObject(entities_plane, entities_point):
    product = app.activeProduct
    design = adsk.fusion.Design.cast(product)
    if not design:
        ui.messageBox('It is not supported in current workspace, please change to MODEL workspace and try again.')
        return
    currentDesignType = design.designType

    global newComp
    newComp = createNewComponent()
    if newComp is None:
        ui.messageBox('New component failed to create', 'New Component Failed')
        return

    newComp.name = 'basePlate'

    #get selected plane
    plane = entities_plane[0].name
    plane = entities_plane[0]

    # add sketch
    sketches = newComp.sketches
    sketch = sketches.add(plane)
    sketch.name = 'basePlateSketch'

    #get selected point
    point = entities_point[0]
    point_align = point.geometry
    #ui.messageBox('Punkt ausgewählt')

    # add circle as sketch curves
    circles = sketch.sketchCurves.sketchCircles
    #circle1 = circles.addByCenterRadius(adsk.core.Point3D.create(point_align.x, -point_align.z, point_align.y), 0.8)
    circle1 = circles.addByCenterRadius(adsk.core.Point3D.create(0, 0, 0), 0.8)

    # Get the profile defined by the circle.
    prof = sketch.profiles.item(0)

    # Define that the extent is a distance extent of 2.5 mm.
    distance = adsk.core.ValueInput.createByReal(0.25)

    # Create the extrusion.
    extrudes = newComp.features.extrudeFeatures
    ext = extrudes.addSimple(prof, distance, adsk.fusion.FeatureOperations.NewComponentFeatureOperation)
    body = ext.bodies.item(0)

    #get circular face or edge for selection and set constructionPoint by center
    edges = body.edges.count
    circularEdge = body.edges.item(0)
    #par = ext.parentComponent
    startFacesObj = ext.startFaces
    startFaceCenter = startFacesObj.item(0).centroid
    ext.name = 'basePlateBody'
    #ui.messageBox('bodies Base Plate' + str(ext.bodies.count))
    
    # get circluar face
    circularFace = None
    for face in body.faces:
           geom = face.geometry
           face1 = face
           if geom.surfaceType == adsk.core.SurfaceTypes.CylinderSurfaceType:
                circularFace = face
                #ui.messageBox('Circular Face')
                break
    

    
    #foundFaces = newComp.findBRepUsingPoint(point, adsk.fusion.BRepEntityTypes.BRepFaceEntityType)
    

    constructionPoints = newComp.constructionPoints

    #creating construction point in the center of the circular face
    pointInput = constructionPoints.createInput()
    #it works with the sketch circle
    #pointInput.setByCenter(circle1)

    #it does not work with the circular face or the edge??
    #pointInput.setByCenter(circularFace)
    #pointInput.setByCenter(circularEdge)
    #pointInput.setByPoint(startFaceCenter)
    #center_point = constructionPoints.add(pointInput)

    #trying to select the face or circular edge: doesn't work
    
    ui.activeSelections.clear()

    # tried different things:
    #ui.activeSelections.add(circularEdge)
    #ui.activeSelections.add(body)
    #ui.activeSelections.add(center_point)
    ui.activeSelections.add(circularFace)

    alignCommand = ui.commandDefinitions.itemById('FusionMoveCommand')
    alignCommand.execute()

 I hope, anyone can help me. Thank you in advance.

[kandennti]

Hi @julia.bergVCCN8 .

When dealing with Occurrence, you need to learn the linked Proxies.

https://help.autodesk.com/view/fusion360/ENU/?guid=GUID-88A4DB43-CFDD-4CFF-B124-7EE67915A07A 

Although not in the desired form, a center point can be created by modifying it in this way.

・・・
    #creating construction point in the center of the circular face
    pointInput = constructionPoints.createInput()
    proxy_circularEdge: adsk.fusion.BRepEdge = circularEdge.createForAssemblyContext(
        newComp.occurrences[0]
    )
    pointInput.setByCenter(proxy_circularEdge)
    center_point = constructionPoints.add(pointInput)
・・・

However, the subsequent processing is not in the desired state, and other problems are likely to arise.