Forest Pack and Xref to library

[GH3184]

Hi. I have a technical performance question about "Xref to library" in the preset window.

"Merge into scene" obviously makes the scene files heavy. Long file saves = Turn off Max' autosave = crash = Homer Simpson. DOH! And trouble with deadlines and lost money = Drink more beer = Alcoholic = Loose job = Woman leaves = House goes = Car goes = Life fucked.

Joke aside, I actually never looked into doing it differently before I accidently saw the "Xref to library" radio button.
The file sizes are bugging me, so "Merge into scene" is obviously not optimal for big vegetation scenes.

I get it that Xref to library doesn't affect the Max file size the same way, but I bet it do affect the use of RAM.
1) Do all the nodes need to load all the Xref'ed files into their RAM, or are they reading in and out along the render, hence slowing the render down?
2) When does it read the source objects in and out from the RAM compared to when using "Merge into scene"?

Bottom line, I'd rather have big file sizes than having the render nodes crash because of overuse of RAM, but I neighter like huge file sizes.
Thanks.

[Michal Karmazín]

Hi,

There isn't any dynamic loading/unloading performed during the rendering (like in case of proxy objects).

1) The geometry is loaded into the memory during whole rendering process. Using XRefs (XRef Objects / XRef Scenes) uses less in the .max scene, but once render starts, all referenced objects are fully loaded in the memory.

2) For render purposes, references are handled in a very similar way as meshes.

Hope that helps.

Best regards,

[GH3184]

Thanks.

So you can confirm that using Xref instead of loading in the scene doesn't make a difference when it comes to the use of RAM?

And basically there are two differences with using xref: 1. You can't change the object directly in the same scene (which you can't when loading presets anyway) and 2. Huge performance increase with the max file, especially regarding to file size and autosave.

Let me know if you know about any obvious downsides of using the Xref load from the preset manager in forest pack.

[Michal Karmazín]

Hi,

You're welcome. Yes, the memory usage during rendering process is the same. Let me add, that XRef Scenes objects within the external file are visible as a reference but cannot be selected, instead in case of XRef Objects depending on the object's XRef settings, you might or might not be able to edit the object’s entities such as its transforms, materials, manipulators, or modifiers.

Specially for complex scenes is generally recommendable to use references. Just take in mind, if you'll modify those referenced files, the scene containing those will be affected too. For this reason, a time ago we've decided to disable XRef for all bundled presets. There is a good reason for that: in this way we can modify these presets on Forest updates (i.e. optimize them, update materials, etc), while keeping the compatibility with existing scenes. If not, a same scene would look differently depending of the Forest version used.

Best regards,

[GH3184]

Thank you for that information! Keep up the good work!