In which cases Bentley Map Topology works?

Question

Hi. I have a file that includes a big amount of Buildings geometry. Some of the buildings are "closed shapes" and possible to see an area of it. But a big amount is not- even Autocad shows that it is a closed polyline. Tried to use 0. Place a fence 1. Bentley Map/Topology/ Create Centroid 2. Bentley Map/Topology/Create Shapes 
 Does not work in some case with my file. Works with other files. Could you check and tell what is wrong? Buildings_for_forum.dgn

Sebastien Lefrancois · Answer

Hi, Topology tools are used to cleanup and create valid topology from line elements. Once it is validated, we will be able to create area from boundaries (line elements). So, when you are using create shapes tool on shape elements, it won&rsquo;t give any results since shape elements are already existing. It should result to a "Found no boundaries". 
 In your file, if I drop shape to line, place a fence around lines and centroids (only one centroid by expected shapes), the Creates Shapes tool work properly to me. 
 I also see you work on 3D model. In case where you have elements on different Z values, you will need to enable Consider Z option in the Preferences > Topology dialog. 
 I hope that helps. Sebastien Lefrancois 
 See help section: Topology Operations

Sebastien Lefrancois · Answer

I do not see the problem in the attached DGN. It recognize the 5 closed elements as shape. Before dropping, you can use Validate Topology tool to target non-closed building. You can also use other topology cleanup tools to found gap and dangles. Once topology is validated, you can use topology creation tools as create centroids and shapes. See online help for details on each tool; to see which one could be useful to you. If you prefer drop all to validate all drawing, you can drop a huge number of elements by selection or by using a fence. Then, pass topology cleanup tool first, and once validated, create topology shapes. Be sure the copy original files before processing. I hope my explanations are clear enough. I hope that helps. Sebastien