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Description

Currently, plate extraction features only work for planar surfaces. When trying to restrict a given non-planar surface (TopoDS_Shell) with a given contour (TopoDS_Wire), the surface extraction fails due to improper imprinting of the given contour.

Problem Statement/Justification

Surface extraction should be supported for all shape types, not just for planar surfaces.

Proposed Solution or API

Quaoar stated:

1. Prepare the input contour to make it composed of splines instead of polylines. We had polylines mainly because it was defined like that in the target system (ship hull modeling system, where plates were captured for subsequent unfolding). With split-by-continuity you can turn it into a wire with C1 edges.
2. Imprint the prepared contour onto the shell. Here we implemented this Contour Capture algorithm mentioned in the link above. You can try using "General Fuse" operator of OpenCascade like here: https://gitlab.com/ssv/AnalysisSitus/-/blob/master/src/asiAlgo/auxiliary/asiAlgo_Utils.cpp#L3486. Use 0.1 as a fuzzy tolerance for Booleans
3. Once the contour is imprinted, it's necessary to filter out all faces lying outside the contour. This can be done by properly iterating the imprinted edges:
   1. Find the center point of the contour and the face closest to this center point. This would be your starting face.
   2. Iterate over the neighbor faces until you reach the imprinted contour bounds (Boolean operation would return you the images of those edges, so you can check if your next face contains these edges or not to decide whether to stop propagation).

Alternatives

No response

Additional Information

Continue here: Analysis Situs Forum

Description

Currently, after creating a Geom_BSplineCurve and returning it as TopoDS_Wire to save into OCAF document, a false representation of the given curve is exported to STEP:

Note: No issues seem to occur when exporting the curve directly after it was created.

Steps to reproduce

1. Run the STEP Export with the following test data: Aveva-OHCM-MidShip_V285.3docx
2. Open the created .stp file and view Panel (ID51)

OCXReader Version

0.1.0

Operating System

• macOS
• Windows
• Linux

Additional Information

Continue here: Analysis Situs Forum