Workplane / Face Based Families Offset Parameter

[mastjaso]

Hi I'm working on a script to realign some light fixtures with ceilings. The only problem is that some of my families will move, and some won't.

These are both face based families, however, for some reason only one of them has an "Offset" parameter, and this is the only one that will move up or down out of it's reference plane when I call ElementTransformUtils.MoveElement.

So why does my Type A fixture have an offset parameter, and why is it the only one that will move?

[Mustafa.Salaheldin]

Please clarify more. I can't get your point.

[mastjaso]

Look under their properties, in the "Constraints" parameter group. The Type A fixture has 3 parameters, one of which is "Offset". The Type E fixture only has 2 parameters.

If you call ElementTransformUtils.MoveElement and try and move them 2' vertically up or down, the Type A fixture will move (and it's "Offset" parameter changes), whereas the Type E fixture will not move. So I'm trying to figure out why one only one of these families has an "Offset" parameter?

[Mustafa.Salaheldin]

This is due to the template used to create the family. Some built-in family templates provide the Offset parameter automatically and some of them not.

Please refer to this article for more explanation.

If this reply satisfies your needs please mark it as an answer.

[mastjaso]

Thank you for that explanation, but is there any way to change their properties and convert between the two using the API?

[mastjaso]

Also, is there any way of telling which way the family was built? As far as I can tell regardless of which template was used the BuiltInParameter.INSTANCE_FREE_HOST_OFFSET_PARAM has value, is not user modifiable, and is not read only so I'm not sure how to tell which way the family was built.

[Mustafa.Salaheldin]

As far as I know, the answer is you won't be able to modify or add the properties by API to get the out of the box ones. Please share a sample file with sample family to see if I can help.