Coron MultiMap in Instance mode - inconsistent behavior when re-rendering

[pokoy]

Cocona MultiMap in instance mode produces different results when re-rendering. I am currently rendering a project via backburner on different machines and each version differs from the previous although the map settings haven't changed. It doesn't seem to happen every time but it happens.

[Ondra]

This is interesting. Could you upload me a (simplfied) version of the scene where it happens?

[pokoy]

This is interesting. Could you upload me a (simplfied) version of the scene where it happens?

I'll try, however this has happened a couple of times only until now so not sure how to reproduce.

Is this something that could be locked/fixed by introducing a seed spinner? If yes, please do so, it would be an excellent addition to the map anyways ;)

[Ondra]

no, if it changes, then it is a bug that has no connection with seed spinner

[PROH]

It does also change object colors in IR (both of them) whenever you select the material in ME (compact) - if the multimap slot is open. It does however render (not IR) with correct colors, even when IR shows different.

Easy to reproduce:
- CScatter a bunch of instances from 2-3 objects with multi map texture and use "Instances" mode in multimap.
- Render to see the colors. Keep a copy as reference.
- Turn on IR, open compact ME and select the multimap material, open the multimap slot (don't change anything), and the object colors changes in IR.
- Select another material and select the multimap material again. Colors changes again in IR.
- When colors have changed in IR, render again. Colors are back to original.

Corona v1.00.02, MaxDesign 2014 with latest SP.

Edit: Made some changes in description to make it more accurate.

[maru]

I confirm all of the above in 1.00.02 and DB.

[pokoy]

Good catch, I couldn't repro this, it was occurring only sometimes (no matter if local or slave, both rendered differently sometimes).

[pokoy]

So I just had it happen again with IR and switching motion blur on and off again, the MultiMap would change in instance mode and look differently in normal rendering mode. The objects using the map are not moving, it's happening as soon as mblur is enabled/disabled.

I am busy as hell and can't take the time to come up with a scene that shows the bug. There have been some repro steps posted above so it should be easier to track that down now. Can we have this fixed. It's really something you can't use in production as long as it's not reliable and produces inconsistent results. (And, please please finally implement that seed spinner...)

[Ludvik Koutny]

Already logged on mantis: https://corona-renderer.com/bugs/view.php?id=1054

Archiving to resolved.