March (mini) Update 2 Climax WIP

Hi, mini update.

Going to start rendering tomorrow.

Why has it taken so long? I had a hard to track down error that took days to fix (see below), then I needed to use a few more days to tweak the fluid/fur sim to get it looking good.

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Reading the following back I sound angry and worked up, because, well, I am a bit. Going to post it anyway, a bit less filtered than I am normally, don't worry I'm doing ok.
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I don't normally go in depth with my technical descriptions because because well, it likely sounds like gibberish. But this time I'm making an exception. I lost five fucking days to a incredibly hard to track down error. I kept going back and forth on making a post saying I just can't have the fluid and fur interact. I stuck it out as I'd already spent so much time on it.

This was the absolute worst error state to diagnose, things working just enough to make you think it's a settings issue. Everything still worked but it kept failing in weird ways. The fur ending up too floppy when it should have been getting stiffer, the fluid sticking too well. Days of slogging through adjusting settings, starting a sim, waiting, repeat.

After multiple days, by pure chance, stepping through the sim with the viewport rotated and zoomed just right to see it, the fur slightly straitened out. The first 3 frames show the fur getting slightly straighter. This meant an external force was acting on the fur when there should not have been one.

The code node responsible for the flick animation. (it adds velocity and lowers the friction in certain spots at just the right time.) was causing the problem, even though it didn't touch the fur! After stripping the code right back, I was left with the single line that caused the issue:

'int target = @target_prim;'

Read the current value of 'target_prim' into a variable called 'target'.  That's it, that's all it should do!

This line changed all instances of 'target_prim' on everything in the sim that was '-1' to '0' It. Adding a second line setting that attr back to '-1' on the hair fixed it. (for the tech inclined unsigned ints don't exist in this software package so not that.)

Finally. After days of trying different settings everything started behaving normally, and I could start the process of fine tuning.
So yeah that's how I spent 5 days of my time recently, if I had not noticed that slight wrong movement I'd have still been trying settings combinations and yelling at my PC.

Doing sim is so frustrating. It takes ages to see any changes you make if the part you need to review is tens of frames into the sim. Full sims can take 3 hours to cook (that's for the fluid and fur pullout shot), some of the caches with post processing can take over an hour to write out. Then if something needs to be adjusted with the animation EVERYTHING need to be re-run from scratch and on top of all that I'm having to track down hard to notice bugs rather than just art direct. I'm going to do several more animations before doing anything with fluid again, It just takes too much time. I understand those who left because I've been spending so much time on this. I'd prefer to spend my time animating.

But anyway, it's going to be rendering soon, I've got a load of moving parts in this, multiple sims softbody, fluid and fur and I did say it'd take a while. I'll be back later on in the month when it's all done.