how to get the center of GeometryInstance

[KM_Yotsuha]

I am going to place  pipe Accessories  on locations where there is a cadblock, in order to get the placepoint of familyInstance,I need to get the center of a geometryInstance。

for example,how to computer the center of blue lines in the picture below?

[jeremy_tammik]

Two easy points to start from are the family instance location point and the center of the family instance element's bounding box:

• https://www.revitapidocs.com/2022/847ff799-9b1b-0982-f55a-7273c55b196d.htm
• https://www.revitapidocs.com/2022/def2f9f2-b23a-bcea-43a3-e6de41b014c8.htm

There are other options available that are more complicated, so I would suggest trying the easiest approaches first.

[KM_Yotsuha]

sorry for my poor English. I don't want to computer the center of a existing family instance, what I want is where to put the newly created familyInstance.

for example,I want to place a pipe accesory according to the cad below.

how  can I get the location parameter? the location point is the centre of a geometryInstance

[Omar_Amen]

Hi @KM_Yotsuha,
if you want to get to correct location to place your instances, then you need to relate with the CAD drawing itself,
let me  assume the best case scenario then  your CAD drawing is clean and:
-the pipe accessories are created as CAD blocks
-the pipe accessories are placed on the same layer (i.e. this layer contain only those pipe accessories)
then you can develop an add-in to get the center point of each CAD block on a layer of name "layer_name_example" that located in the CAD drawing that linked in that Revit document.

*hint: I don't know if you can retrieve the locations data using only the Revit API so I think you will need to use the AutoCad API to relate with the Cad drawing 

[KM_Yotsuha]

thank you~~ I can use cadblock's location property,but some block's center is not equal to location point.

how can I computer the center point of blocks like the one below?