| Cause Category | Specific Trigger | |----------------|------------------| | | A specific solid, region, or surface in the drawing contains non-manifold edges, zero-thickness faces, or internal topological errors. | | Conflicting Object Enablers | Third-party enablers (Civil 3D, Mechanical, Inventor Link) overwrite or conflict with the native acismobj20.dbx . | | Graphics Driver / Hardware Acceleration | Faulty OpenGL/DirectX calls during 3D orbit, shading, or regeneration. | | File Corruption | The .dwg file itself has a damaged ACIS stream in its database. | | Custom LISP/VBA/ARX | A routine forces an illegal ACIS operation (e.g., subtract with invalid intersection). |
| Cause Category | Specific Trigger | |----------------|------------------| | | A specific solid, region, or surface in the drawing contains non-manifold edges, zero-thickness faces, or internal topological errors. | | Conflicting Object Enablers | Third-party enablers (Civil 3D, Mechanical, Inventor Link) overwrite or conflict with the native acismobj20.dbx . | | Graphics Driver / Hardware Acceleration | Faulty OpenGL/DirectX calls during 3D orbit, shading, or regeneration. | | File Corruption | The .dwg file itself has a damaged ACIS stream in its database. | | Custom LISP/VBA/ARX | A routine forces an illegal ACIS operation (e.g., subtract with invalid intersection). |