File size of f3d exports with suppressed features

[edgemarston]

I noticed some odd behavior of f3d archives. I exported a project into a 35.1 MB f3d file. Then I exported the same project after making no changes other than suppressing a number of features in the timeline. The new f3d file was 19.4 MB.

I don't get how this is possible. If an f3d file is capturing all the relevant data for the project to be imported and re-created, then the file sizes should be very close to identical, right? The data about which features are suppressed must only be a few kilobytes. This isn't like STLs where the size of the file would go down if you suppress a bunch of features that create complex new bodies. In this case the exact same data comprising the feature timeline are still there. Suppressing should make no difference.

What am I missing?

[HughesTooling · Accepted solution]

The f3d does contain a smb file(similar to SAT), it is not regenerated from scratch when you import. Hard to know how much info's in the file without seeing it, can you share any pictures, with and without the suppressed features.

Mark

[edgemarston]

Hi @HughesTooling, thanks for the quick reply. I don't have that project handy right now, but given what you said about how the f3d file does contain actual 3D geometry, I think that explains it. I was just very surprised because I assumed the f3d was more like a parametric instruction set for re-creating the project step by step (as that would seem to be the most space-efficient way to encode the data). I didn't realize the actual solid bodies were contained in there too.

The reason I started worrying is that I was concerned that suppressed features weren't being exported along with the rest of the project, which would be a big problem for backup purposes. But it looks like everything is okay (minus perhaps some unnecessarily-large files).

[piperVVYZ3]

I just came here curious why my .F3D file for one particular project was even larger than the .gcode file produced from it.  Made no sense to me at all.  But this would explain it.

The model includes a significant block of embossed text. That's probably what's taking up so much space in the .f3d.