Partition

For a detailed description of the Partition operation please refer to this document. It provides a general review of the Partition and Boolean operations algorithms, describes the usage methodology and highlights major limitations of these operations.

Perhaps you also ask yourself : What's the difference between partition, compounds and fuse operation?

To produce a Partition in the Main Menu select Operations -> Partition

This operation builds a compound by partitioning a set of input objects by a set of tool objects.

The Result of the operation is a GEOM_Object.

Arguments: Name + 2 lists of shapes (the shapes from the first list will be intersected with the shapes from the second list) + Resulting Type of shape.

As far as the partition of two objects can produce any type of geometrical objects, Resulting type box allows choosing the preferable result, i.e. a solid, a shell, a list of faces, etc.

The Resulting type has to be equal or lower than the type of the Objects. In other words, if the Objects don't contain any shape of this type, Partition fails.

Keep shapes of lower type checkbox manages standalone shapes of type other than the Limit. If it is checked, lower dimension objects will be preserved, else they will be lost.

For example, you partition a box (Solid) and a face (Face) without any tool (the box is split in two parts by the shape). If you choose the Resulting Type "Solid", you will obtain a compound of two solids, but if you also check Keep shapes of lower type checkbox, you will obtain a compound of two solids and one face (there will be a hole in the resulting face, where the original face intersects with the box, see the corresponding picture below).

No sub-shapes intersection (Compounds only) check box affects only input shapes of the Compound type.

• If this option is switched off (default behavior) each input compound will be automatically exploded into sub-shapes and the partition between these shapes will be also computed.
• If this option is switched on, the partition between sub-shapes will not be performed. In this case the Partition algorithm will work faster, but the result might differ from the default behavior.

Detect Self-intersections check box is used to check self-intersection of arguments. It is enabled only if No sub-shapes intersection (Compounds only) is checked.

• If this option is switched off (by default), the partition algorithm is performed without self-intersection checks.
• If this option is switched on, each input shape is checked for self-intersection. If self-intersection is detected, the operation is aborted.

Note

This algorithm does not find all types of self-intersections. It is tuned to detect vertex/vertex, vertex/edge, edge/edge, vertex/face and edge/face interferences. Face/face interference detection is switched off as it is a time-consuming operation that gives an impact on performance. To find all self-intersections please use Detect Self-intersection tool.

• Activate Advanced options if required.

Note

Partition is a complex operation, so its result of it depends on the quality of the initial shapes. Sometimes, if partition fails, such healing operations as Shape Processing and Limit Tolerance can help to attune source shapes to obtain correct result of the Partition. See also TUI example of shape healing.

TUI Command (with sub-shapes intersection):

geompy.MakePartition(ListOfShapes, ListOfTools, ListOfKeepInside, ListOfRemoveInside, Limit, RemoveWebs, ListOfMaterials, KeepNonlimitShapes)

TUI Command (without sub-shapes intersection):

geompy.MakePartitionNonSelfIntersectedShape(ListOfShapes, ListOfTools, ListOfKeepInside, ListOfRemoveInside, Limit, RemoveWebs, ListOfMaterials, KeepNonlimitShapes, checkSelfInte)

Here,

• ListOfShapes is a list of shapes to be intersected
• ListOfTools is a list of shapes to intersect the shapes from ListOfShapes
• Limit is a Type of resulting shapes
• KeepNonlimitShapes is a flag that allows to preserve standalone shapes of low dimension (than Limit) in the result.
• checkSelfInte is a flag that indicates if the arguments should be checked for self-intersection prior to the operation.
• Other parameters are obsolete and kept only for compatibility with previous versions of SALOME.

Examples:

Input data: box intersected by plane

Result: box partitioned by plane

Result: partitioned box and plane (both as Objects); resulting type is Solid; option 'Keep shapes of lower type' is on

Our TUI Scripts provide you with useful examples of Basic Operations.