Why does Vray load in bitmaps of (some) objects hidden in the scene?

[Vizioen]

I was testing some things just now and I opened one of my templates. This is a template with a few objects, forest pack and railclones and 50 some materials in slate editor. I enabled memory tracking in the render settings to see what is being used.

So I isolated a forest pack object of some grasses and drew a plane with no material and distributed the forest, the rest of the objects I hid. So in theory, when rendering I should only have the textures of the grasses loaded no other textures.

But to my surprise, I saw a lot of other textures, concrete, wood, license plates, solar panels, roofing, carpet textures, etc

To be sure I selected the hidden objects put them on a new layer and hid the layer. But results were always the same. 30 some textures that aren't used in any way. But not all of the textures that are used on objects in the scene either.

So why does V-Ray load in these textures? It seems quite random.

[Joelaff]

Was this with VrayBitmap nodes? Or Max Bitmap nodes? The Max nodes load regardless, ifrc.

[will_will]

I guess that not only for rendering , some effects like dislpacement or scattering still require the textures .

[Vizioen]

Yeah but the textures being loaded have nothing to do with any effects, displacement or scattering and they aren't linked in anyway to what is being rendered. It's was just 3 grass plants being scattered on a material-less plane.

I just made a new test in this template, this time I'm literally only rendering a dome light in a camera. So no geometry and apart from the EXR map for the lighting, nothing should be loaded, but all the same textures as last time are loaded. Mind you this is 3.5GB of unused textures.

Things I've tried to have them removed:
- Reset render settings
- Put everything on a hidden layer and set the layer to not render.
- Reset both material editors so they didn't contain any maps or materials.

Anyone from Chaos that can shed a light on this? I just want to understand why these maps are loaded when nothing is apparently using them.

[^Lele^]

It'd be best if you sent us the scene for investigation.
I'm not able to repro the behaviour (max 2023) you describe: for hidden (and ofc unrelated to the rest of the scene) objects V-Ray skips the shader (and stuff like the displacement modifier) entirely.

[Vizioen]

It'd be best if you sent us the scene for investigation.
I'm not able to repro the behaviour (max 2023) you describe: for hidden (and ofc unrelated to the rest of the scene) objects V-Ray skips the shader (and stuff like the displacement modifier) entirely.

I'll upload the full scene, as I don't know what will cause this, so best not to strip too much. Can I send it to you?

[^Lele^]

Sure, poke me via email with a link, i'll take a look immediately.

[Vizioen]

So for those with the same question in the future. All was good actually, it's just the cache from opening a Max scene:

Copy paste from my conversation with Lele:

"Oh, those aren't "loaded", they are "cached" from the Max scene opening.
Tick on "clear cache on render end" in the tiled texture rollout, and they won't show up in the mem tracker if the nodes aren't visible at rendertime (i.e. they get unloaded. and reloaded if needed when max gets the control back.)."

Thanks again Lele!