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Limitations
Intersections may yield several geometries. LOP chooses geometry that leaves the body locally valid and with the same edge convexity as the original body if possible. The body is only checked to be locally valid. If non-neighboring faces interpenetrate they are not detected, and a self-intersecting invalid body will result unless lop_repair_self_int is on, in which case these bodies will be healed.
If any intersection yields no geometry, local operations fails unless a suitable topology change to the model is supported. Topology changes are not permitted except for those described below.
Model surfaces and curves are extended by all local operations except tweak if they can provide good estimates for the required extension. All local operations are tolerant modeling friendly. This means that local operations behave sensibly when tolerant geometry is encountered. When lop_repair_self_int is on, LOP can make tolerant edges as necessary to successfully complete the operation.
LOP has the following limitations:
- The original and final body must be manifold and solid.
- No other topology changes than those documented are permitted.
- Tweak faces does not extend the geometry of the tool surfaces or their neighbors, unlike the other local operations, which do. (However, api_tweak_extend_faces can be used to extend surfaces and curves before a tweak operation.)
- Some options may be mutually exclusive. Be sure to check the reference documentation.
Geometry Changes
- pipe_spl_sur spline surfaces are converted to rb_blend_spl_sur spline surfaces in the supplied faces and their neighbors if the option lop_convert_pipe is set on, which is the default setting.
Topology Changes
- Mergeable edges and vertices on the supplied faces are merged out.
- Edges and vertices between faces that are tweaked to the same geometry are merged out.
- Two edge vertices on the supplied faces between edges on the same geometrical nonanalytic intersection curve are merged out by lop:tweak-faces if the option lop_merge_vertex is set on and if not presently merged elsewhere. This is the default setting.
- Vertices with more than three edges may split into two or more vertices during a local operation. Single inverted faces are created if needed to fill any gap in the body. If two or more inverted faces are needed, the operation fails.
- Self intersecting bodies that result from LOP can be healed by turning the option lop_repair_self_int on.
- Edges in multi-edge loops may degenerate exactly to a point and are removed.
- Isolated single edge loops may degenerate exactly to a point or be removed altogether. Their faces are deleted when appropriate.
- If an edge exactly degenerates to a point in a multi-edge loop, the edges on either side are detected and become fully or partially coincident. The loop is repaired by splitting it into valid, degenerate loops. Degenerate loops and their faces are deleted, when appropriate.
- When faces have been deleted, their shells and lumps are repartitioned and split if necessary.
Related topics:
Types of Local Operations
Topology
Adaptive Offset
Body Repair
Blended Faces
Remove Faces
Defeaturing[Top]
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