FileOut POP Bug + Question

[watershed]

Windows 11 // TD 2025.31760 // RTX 4090

Bug (I think) - When selecting output in the SPZ option, the POP does not allow a user to use attributes to assign fields (e.g. they are all greyed out)

Question - When I read in a splat file (.ply) and then use FileOut POP to output the same, unmodified file just wiring it into a FileOutPOP and assigning the attributes appropriately, the size of the popout.ply is ~5x the input (241mb vs 90mb). Hoping someone can shed some light on what is going on under the hood to cause this.

[huck]

Hello,

This is a bit poorly documented which I will update in our wiki but for the SPZ file it looks for a predefined set of Point Attributes, P, Color, Rot(float4), Scale(float3), and Sh(float3[15]). Sh can have different array entries (0, 3, 8, 15) depending on the spherical harmonic degree. These are the same attributes filled when opening an SPZ file in Touch.

The issue with the PLY file does sound like a bug if you can provide us with the PLY file that I can use to reproduce I will take a look.

Thanks,

Huck

[watershed]

Thanks Huck! So I just need to pre-create those attrs before the file out pop for spz.

For the PLY issue - here is the file to show my file out pop setup

Here is a link to the input PLY: Dropbox

It is ~91mb, the popOut.ply is 237mb on my machine

popFileOut.2.toe (2.8 MB)

[huck]

Yep, all those attributes are necessary except Sh. Thanks I’ll take a look at the PLY issue!

[watershed]

confirmed SPZ save works when the attrs are pre-created. Couple questions:

1. The hardcoded attr names in the SPZ FileOut are different from the auto-populated attrs on the FileIn when loading an SPZ file - seems they should be consistent? Specifically the sh attrs are renamed acc to splat naming conventions, f_rest etc (see below)

2. Some deleted attrs are still populating (e.g. InitScale) i am deleting with an AttributePOP before the FileOut, but still seeing. Not breaking anything, but strange (the file out POP was recreated after the attr pop was added so it was not a caching issue)

   popFileOut.3.toe (2.8 MB)

   

[huck]

For the file size different it seems to be due to the fact that input file is saves as a binary PLY file while File Out POP saves it in an ASCII format. I can look to expose this as a parameter, doing it manually saves it out to a file size of ~86mb
Dropbox to binary popout.0.ply

1. It seems Rot should be changed to Rotate as that is what it gets imported as when dragging and dropping SPZ files. As for the naming conventions they were chosen to take advantage of POP attributes such as array attributes for Sh.
2. I’m not quite sure what you mean by deleted attributes are still populating, is this related to the screenshot you attached below? Could you outline steps to reproduce. The POP cooks when recording so if any changes are done earlier it would only be updated after writing a frame / recording.

[watershed]

1/ Agree with you re: Rotate. Regarding the sh array, i meant that sh gets saved to f_rest but then on drag/drop of spz file the point file in that is created is looking for sh

FileOut:

FileIn:

2/

I’m not quite sure what you mean by deleted attributes are still populating, is this related to the screenshot you attached below? Could you outline steps to reproduce. The POP cooks when recording so if any changes are done earlier it would only be updated after writing a frame / recording.

In the file attached

popFileOut.4.toe (2.8 MB)

. PointFileIn2 creates InitScale, attribute1 renames then deletes it, yet FileOut still displays it as the attr name (in spite of rename)