From #67: the three sample_AC1032.dwg ACIS records agree on the first two of the seven bits between the R2013+ marker and the RFC-4122 v4 revision GUID (1, 0) and diverge after; B,BB,BB,BB and 3B,BB,BB both fit. Separately, whether the inline SAB envelope's absence (data record moved to AcDb:AcDsPrototype_1b per section 24.2.2.3) keys on the flag or is unconditional R2013+ is untestable on this corpus — every ACIS record here sets the flag. A flag-clear or non-R2018 3DSOLID decides both; the decoder fails the boundary check rather than guessing. Also: pre-R2010 ACIS records stay Unhandled because checked_inline's boundary only exists for R2010+ — wiring the R2004 obj_size_bits boundary covers them once a corpus file exists.
From #67: the three sample_AC1032.dwg ACIS records agree on the first two of the seven bits between the R2013+ marker and the RFC-4122 v4 revision GUID (1, 0) and diverge after; B,BB,BB,BB and 3B,BB,BB both fit. Separately, whether the inline SAB envelope's absence (data record moved to AcDb:AcDsPrototype_1b per section 24.2.2.3) keys on the flag or is unconditional R2013+ is untestable on this corpus — every ACIS record here sets the flag. A flag-clear or non-R2018 3DSOLID decides both; the decoder fails the boundary check rather than guessing. Also: pre-R2010 ACIS records stay Unhandled because checked_inline's boundary only exists for R2010+ — wiring the R2004 obj_size_bits boundary covers them once a corpus file exists.