Endless Save - Dforce problems with saving a scene

brownedave2

I've been doing a few Dforce simulations recently.  Basic stuff, some hair or cloth settling over 100 frames or so.  The simulation goes fine.

 

A problem comes when I go to save the scene after doing a simulation.  It just hangs.  See the attached image.  I can cancel the save, which will crash the software.  Or just wait endlessly for nothing to happen.  If I crash the software and do the simulation again, I will find myself at the same place, unable to save the scene.  What is causing this?

 

 

brownedave2

Further details.

I tried doing a test simulation in the same scene using only the first ten frames.  I was able to save that, the save took about 5 minutes, but it did work.

I have done the full simulation again and am trying to save it.  The simulation itself took about 1 hour for some d-force hair, and a basic shirt element.  The simulation worked out well and plays back nicely.  I am trying to save this now with the thinking that it may simply take a really really long time to save for whatever reason.  Currently, I am at the 30 minute mark (saving file... writing assets...).  If it does work, it is looking like saving the scene will take longer than doing the simulation itself.  That doesn't seem right. I'll update this in an hour or so.  

edit: 40 minutes in and I opened the windows task manager to check system usage.  Curiously, this action closed the save progress window in Daz and unfroze the software.  I then closed Daz down, reopened it and tried opening the file.  It seems not to have saved properly.  So i'm now re-simulating, and trying this again.

brownedave2

Did a shorter simulation of 60 frames rather than the full length.  Same problem, save process hangs.  Log file is of no use as it doesn't record anything at the time of the save.

Repeated simulation without hair, using only the shirt.  It saved with no problems this time, good, maybe.  Going to try with only the hair next.

Simulating with just the hair.  Simulation is fine, but when I go to save it hangs.  Great, found the problem.  But, why is this happening?  The product is this one here:

dForce Windflower for Genesis 3 and Genesis 8 Females | 3D Models and 3D Software by Daz 3D

Which, is great looking work by the way.  Looks really nice when simulated... i'd like to be able to save the file though.  Could anyone out there who also has this product try this out?  Do a simulation with this hair and try saving your scene?  I don't know how else to trouble shoot this problem beyond this point.

edit: I deleted the hair from the scene, and reloaded it onto the character before doing another simulation, in case I set some odd setting somewhere.  Same problem.  Unable to save scene simulations that include this product.

brownedave2

Further details.

I tried simulating a different hair product, this resulted in the same problem.  I will try a third to confirm this.

So, it looks like the problem is that when I do a simulation on some hair, it can't be saved without the program hanging.

brownedave2

Stranger and stranger.  Glad I did a third test to confirm.

I was able to save without issue when I simulated the Longdrape hair product, I will try a fourth.  Maybe it is the product(s) that are causing the problem afterall.  So, what is going on with the two that cause it to freeze?

brownedave2

Ok, here's what i've got.

Ezra Hair - savable

Longdrape Hair - savable

Soft Curls Hair - unsavable

Windflower Hair - unsavable

What property shared by these two products is causing this?

brownedave2

Holy crap, it saved this time.  Simulation took 40 minutes.  Then when I saved it, the scene took 40 minutes to save.  Yet, a different set of hair takes 2 second to save after doing a simulation.  What the hell is going on here?

edit: I may have spoke too soon.  The save prompt sure went away on its own.  Trying to load that save file now, it is taking a long time.  I don't think it saved properly, or at all.

 

Note to self - in the future, don't buy Dforce hair.  It doesn't work half the time.  Not worth the time wasted troubleshooting it only to find no answers.

Richard Haseltine

The simulation has to save the final position, and for an animated simulation all of the intermediate positions too, of each vertex. That is potentially a lot of data. Compare the sizes of the slow and fast save scenes - I think you will find that the slow one is much larger than the fast one.

brownedave2

Richard Haseltine said:

The simulation has to save the final position, and for an animated simulation all of the intermediate positions too, of each vertex. That is potentially a lot of data. Compare the sizes of the slow and fast save scenes - I think you will find that the slow one is much larger than the fast one.

It makes no sense to me that the simulation would take 40 minutes, and then saving the scene containing that simulation takes a further 40 minutes.  That does not follow.  

You're correct that the sizes are different.  The simulation in question is a whopping 10 gig file for only 270 frames, where the other one is only 21 megabytes.  I guess this speaks to very different construction techniques on part of the creator of hte products.  The first one was created in such as a way as to be essentially unusable, whereas the second was created properly.  I'll avoid buying any of these in the future, I don't ahve time to do this kind of testing myself to see if they have been made in a way that is usable or not.

arstropica

This post saved me a ton of time and experimentation. 

I was experiencing the same issue with MRL dForce Mid Length Hair for Genesis 8 Female. I can save the scene if there is no hair simulation, but with the simulation, it takes forever.  I will try to submit a bug report for the product.

cajhin

Well, more detail is always nice but expensive. Goes for dForce hair, subDiv level and skin maps. High detail makes sense for closeups, but will murder you in a street scene with 10 characters.

I've played with MRL dForce Long Hair in a timeline, *that* was a beast to save and load. Insane filesizes with only 30 frames. I still like that hair, for its high resolution and fine strands, but I will never again use it on a timeline.

PhilW's Longdrape Hair is much, much lighter - but then, the MRL hair can look better if you use it wisely. In a single frame scene, I don't care much if the file is 2MB or 50MB.

Upshot, expensive dForce hair isn't bad, it's just the wrong tool for a 270 frame scene.

arstropica

Yeah, it's a fantastic looking hair ... if you can get a second mortgage for the disk space!  

null_kinoko_5f2999d2d9

I can save without freezing if I set the simlation range to 10 frames each.

If I set the range to 15 frames, it freezes on my PC environment.