STEP Export/Import Quality - Circular Test

Am I being unreasonable, or is the expectation that the OCCT STEP export tool (no XDE or OCAF) should create a file which, if imported back into OCCT thru that same STEP import engine, should reproduce the original design file faithfully?

If I am not being unreasonable in my expectations, where could I locate the OCCT models and STEP output/input files that were used for the circular quality testing which demonstrated the successful replication of the full range of features/attributes in original input (no disctinction)?

Thank you.

Kirill Gavrilov's picture

STEP export is an export operation, not just a persistence for OCCT shape definition. Due to inconsistencies between STEP and OCCT B-Rep definitions, not every valid OCCT shape could be replicated as is in STEP - export tool has to adopt model to some exchange rules and import tool performs various adaptations and shape healing steps as well.

Of course, STEP export/import in OCCT tries it best to solve inconsistencies in the way to be able to re-import the same model without loosing critical information / corrupting geometry.

There are some automated tests that tries to perform re-import / re-export loop, but I don't know exactly which ones do that, probably they are in "tests/de" group.

(no XDE or OCAF)

....

successful replication of the full range of features/attributes in original input

STEP file format features are mapped to XCAF document structure. Without document, you may talk only about replicating geometry, not "full range of features/attributes".