Split Objects

In construction, everything happens in a location. Estimating costs, production planning and scheduling, procurement, and, for example, onsite management all benefit from adding location information to building elements. Location information is usually not in the model you get from the designers. Nor should it be. You can use the Split Objects tool to add location information to your models in an open, centralized and automated way.

Locations are defined with so-called location prisms. These solid 3D objects define the volume that the location occupies. The prisms can be in the original model, you can create them inside Simplebim, or you can create them in some model author tool and merge them into your model.

The location is for a building element is based on the location prism it's inside. The building elements can be split at the borders of the location prisms.

In addition Split Objects tool can be used, for example, isolating parts of big models into submodels, splitting the pour areas, and so on...

Settings

Objects

To use the Split Objects tool, you need to have a group that contains the objects that you want to split, or for which you want to resolve locations. You can use implicit groups like 'All', you might already have a group in your model, you can create the group manually, or you can create the group within the dataflow automatically.

Location Prisms

Location Prisms defines the group of objects that contains the location prisms used in splitting or resolving the locations. The prisms must have volumetric and solid geometry. You should not use an overlapping prism. Note that you can run the tool multiple times on the same model.

The prisms can be either created inside Simplebim, be the original objects of the imported model, or be merged from another IFC model.

Type

Type defines whether the tool splits objects or not, and how the split is done.

Basic

Basic mode splits objects and resolves locations for the Objects. Note that only splits, that result to objects that have larger dimension than the Minimum Distance are done. The distance is calculated perpendicular to the surface of the location prism, that splits the object.

Locations Only

Locations Only mode does not split the objects. It only resolves the locations based on the given location prisms. One object can have only one location for each run of the tool. The Objects are assigned to the location, which contains the most of their the volume.

Many times, you don't want to split the objects, but you want to assign a location for them. For example, splitting a window doesn't usually make any sense. That would not reflect the reality. You don't assemble windows in two or more parts.

Smart Horizontal

Smart Horizontal mode splits objects and resolves locations for the Objects with some additional smartness compared to Basic mode. 

Many times it doesn't make sense to split objects horizontally, for example, slabs. Smart Horizontal mode tries to avoid horizontal splits, addition to taking into the account the basic minimum distance.

You might want to use this, because the models and prisms are not perfect. They are made by humans. But you might also want to use this, so that you can keep your prism simpler.

Smart Longitudinal

Smart Longitudinal mode splits objects and resolves locations for the Objects with some additional smartness compared to Basic mode. 

Many times it doesn't make sense to split objects longitudinally, for example, walls. Smart Longitudinal mode tries to avoid longitudinal splits, addition to taking into the account the basic minimum distance.

You might want to use this, because the models and prisms are not perfect. They are made by humans. But you might also want to use this, so that you can keep your prism simpler.

Connection Name

The result of the Split Objects tool is connections between the Objects and Locations Prisms. Connection Name defines the name of the property, where the connection is assigned to. 

Make sure you use unique names, if you want to run the tool multiple times on the same model (and don’t want to update or override the existing connections). The Connection Property can be used for example in the Calculate Properties for Connected Objects tool.

Override Connections

Use this option to choose whether you want to override (checked) or update (unchecked) the Connection Property, if it already exists in the model. There are use cases for both. Maybe you want to run the tool multiple times for the same building elements. Then you want to update/add to the Connection Property. On the other hand, if you make a mistake, you can override the Connection Property with a rerun.

Minimum Distance

Usually you want to avoid splitting building elements into very small pieces. Minimum Distance allows you to control how small pieces are left behind.

Remove Original Quantities

Removes all the original quantity properties from the split object.

When a building element is split, a new building element object is created and all the properties from the original object is copied to the new one. Model author tools many times include also quantity properties to the building elements. However, after splitting the original quantities naturally now longer are correct. Usually you want to remove these quantity properties from the split object so that there is possibility to use the wrong quantities when using the data of the split objects. The new quantities can be calculated using Simplebim's Calculate Quantities tool.

Add Properties

Add Properties adds Parent Guid and the Result Type of the splitting to the processed objects. This is a legacy functionality, which is not usually needed. Use this only if you needed the parent guid and result types.

Propertyset Name

The property set name where the Parent Guid and Result Type are assigned to.

Parent Guid Property

The name of the Parent Guid Property. The value will be the guid (global unique identifier) of the original object. Use this is you want to track in your downstream application, which original object was used for creating the split object.

Result Type Property

The name of the Result Type property. The value can be either SOURCE, RESULT OR ERROR. Source means, that the object was not split. Result means that the object was split. Error means that the splitting failed somehow. 

How does it work?

Splitting

Splitting happens at the borders of the location prisms. Let's say you have a wall that is located inside two different prisms. The result of splitting is two separate wall objects. Both of them have all the original properties, they are placed in the same to the model tree, and are assigned to the same groups as the original wall. In addition to this, the walls have a connection to the location prism after the splitting. This connection can be used for setting the actual location property for the walls, or for creating a group for each location prism. The group can contain all the building elements within the given location prism.

Resolving Locations

Location of a building element is defined by the location prism, which contains most of the building element's geometry. The Split Objects tool creates a connection between the location prism and the building elements contained by the location. This connection can the be used in your dataflow to copy location identifiers from the prisms to the building elements, or for example, to create groups based on the connections.

Copying the Location Identifiers Using the Connections

Split Object tool connects the builiding elements to the location prism objects. This connection can then be used for enriching the building elements further.

The basic enrichment you can do is to copy the location identifier from the location prism to the building elements. However you can copy any information you need. To copy the information via the connection, use either Copy Properties or Calculate or Aggregate Properties for Connected Objects tools.

Creating Groups Based on the Connections

The connection can also be used for creating group of objects based on the connections. For example you could automatically create a group for building elements within each location. Use the Create Groups for Connected Objects to do that.

You can add these tools as part of the same dataflow used for splitting the objects, or create a separate dataflow to process the data further.

Handling of Assemblies

IFC models have a hierarchical model tree. The tree includes so-called spatial objects like sites, buildings, building storeys, and spaces. In addition, the building elements can also be hierarchical. The Split Object tool can split the leaf objects of the hierarchy, which usually contain the geometry. 

However, it can also split the parent objects from any level of the hierarchy. What gets split depends on the objects you include in your target group. If you give only the leaf nodes, then only they get split. Suppose your Objects includes objects from the higher level of the hierarchy, for example, an element assembly or even a building. In that case, addition to the Objects, everything below that object in the model tree will get split.

Mapping Guids

Splitting creates new objects to the model. The tool will generate new Guids for these objects. What if you get an update of the split model, and you want the updated split model have the same Guids as the previously split model? You can use Map Guids tool for doing this. See more about the mapping guids from here.

You can add Map Guids tools as part of the same dataflow used for splitting the objects, or create a separate dataflow to process the data further.

Calculating Quantities

When an object is split, then it doesn't any more have the same quantities as the original objects. You can automatically remove the original quantity properties from the objects. Or you can keep them as a reference, if needed.

To calculate the new quantities for the split objects, you need to use the Calculate Quantities tools. You add them to your dataflow after the splitting, or calculate quantities separately. The split objects are always included in the target group you gave to the Split Object tools, so you can use that as a target for your quantity calculations.