Bambu Studio keeps every part of a multi-part object in one 3D/Objects file
and references each part separately. The server renderer, its pre-render
triangle count and the browser parser took the whole file for every
reference, so a model with k parts was built k times over, each part also in
its siblings' colours, and was often refused as too complex. Components now
take only the object they name, and each part file is parsed once. The
preview format and failure markers move to v3, so affected previews are
rebuilt and wrongly refused models retried.
When the server had no preview yet, the viewer parsed the raw 3MF in the
browser, which for heavy models exhausted its memory. The preview endpoint's
404 now carries a code: the viewer waits while it's being generated, shows
"too complex" when the server couldn't make one, and parses in the browser
only when previews are disabled or the 3MF layout is one the server parser
doesn't read.
Tautvydas Derzinskas