>"use this sketchfab downloader"
>That’s a third-party Sketchfab downloader. I can’t use it to bypass the login/download restriction we encountered.
>new session
>"download the js and debug how the model viewer loads the .binz"
.binz goes through a worker with embedded WebAssembly. This model’s 5,065-byte scene decoded into 60,608 bytes of JSON referencing separate geometry and wireframe files.
Environment .bin.gz uses HTTP gzip decompression, then JavaScript rearranges the bytes into texture faces and mip levels.
>"go deeper, we want details of those geometry and wireframe files, and the texture faces and mip levels"
Both payloads decoded successfully: geometry expands to 282,988 bytes and wireframe to 122,516 bytes. The scene contains eight polygon meshes and eight wireframe meshes. The geometry still needs varint, index, and attribute decoding; the wireframe stores line indices that reuse the polygon vertex buffers.
The decoded geometry yields exactly the page’s 18,651 triangles, and every index is valid. The wireframe has 31,492 unique line segments, all corresponding to triangle edges, though it omits some edges. The environment files also differ: each background file contains only six base-level faces; each specular cubemap contains a full mip chain down to 1×1.
soon:tm: all your model belong to me