motion blur frost mesh help?

[super gnu]

Im using frost to mesh some fluid type particle sprays. 

this allows me to render on vray gpu, which is nice and fast. 


however when i enable mortion blur, and hit render on a given frame (even with flow cached to ram via playback)  my entire tyflow recalculates, *several times*, from frame zero before rendering..  this takes 3-4x longer than the render itself. 

then, as if that wasnt annoying enough, the frost mesh doesnt appear to actually have any blur on it. 

is there a way to cache the tyflow which will work immediately with moblur without recalculating? 

anyone advise how to get moblur on the frost mesh? it has a few diff moblur settings.

[Ruffstuff]

I noticed my flow evaluating several times also, but it was't only when rendering. (I cant help with the motion blur problem)

[tyFlow]

If you're noticing problems like this, please send the file to support@tyflow.com. There could be a variety of things causing the recalculations. One thing you can do on your side is enable "print sim reset info" in the debugging panel of your tyFlow. Then watch the maxscript listener to see if/when it prints out which reference node is causing it to reset and recalc.

Also if you don't have caching enabled, rendering with moblur will cause a reset because max will query past frames for the moblur interval. So for example, if you render frame 100, the renderer may ask for frame 99.5 and 100.5 to calc the motion blur interval....but since tyFlow is history dependent, if you have caching disabled it will have to recompute the entire sim to query the previous frame.

[super gnu]

thanks for the replies.. ill save out a file to send later.. Tyson, do you have Frost? im not sure if its a tyflow or frost or vray next gpu issue that is causing my complete lack of motion blur.,

strangely, despite doing all that recalculating on render (it is already cached)

if i turn on that camera multipass motion blur on the max camera, and hit preview, the viewport happily does 12 subframe samples of the frost mesh, without any recalculating.

i also tried exporting the frost mesh as an animated vray proxy, and that too, rendered without moblur.

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this is what i get in the listener when i hit render on frame 2 of my sim:


tyFlow002: [CACHE]: [frame: 2.00] [particleCount: 88839] Time: [buildMesh: 0.00297]
tyFlow002: [frames: 0-1 (8 steps)] [particles: (live: 88839 | pool: 11161 | allocated: 100000)] Time: [startSim: 0.506s] [stepSim: 6.293s] [physics: 0s] [buildMesh: 0.00314s]
tyFlow002: [frames: 2-2 (1 steps)] [particles: (live: 88839 | pool: 11161 | allocated: 100000)] Time: [startSim: 0s] [stepSim: 0.634s] [physics: 0s] [buildMesh: 0.00319s]
tyFlow002: [CACHE]: [frame: 1.75] [particleCount: 88839] Time: [buildMesh: 0.00272]
tyFlow002: [frames: 2-2 (1 steps)] [particles: (live: 88839 | pool: 11161 | allocated: 100000)] Time: [startSim: 0s] [stepSim: 0.739s] [physics: 0s] [buildMesh: 0.00399s]
tyFlow002: [frames: 0-2 (9 steps)] [particles: (live: 88839 | pool: 11161 | allocated: 100000)] Time: [startSim: 0.425s] [stepSim: 6.951s] [physics: 0s] [buildMesh: 0.00336s]
tyFlow002: [CACHE]: [frame: 1.00] [particleCount: 88839] Time: [buildMesh: 0.00273]
tyFlow002: [frames: 0-1 (5 steps)] [particles: (live: 88839 | pool: 11161 | allocated: 100000)] Time: [startSim: 0.516s] [stepSim: 4.395s] [physics: 0s] [buildMesh: 0.0032s]
tyFlow002: [frames: 1-1 (1 steps)] [particles: (live: 88839 | pool: 11161 | allocated: 100000)] Time: [startSim: 0s] [stepSim: 0.652s] [physics: 0s] [buildMesh: 0.00353s]
tyFlow002: [frames: 1-1 (2 steps)] [particles: (live: 88839 | pool: 11161 | allocated: 100000)] Time: [startSim: 0s] [stepSim: 1.336s] [physics: 0s] [buildMesh: 0.01165s]
tyFlow002: [CACHE]: [frame: 1.00] [particleCount: 88839] Time: [buildMesh: 0.00269]
tyFlow002: [frames: 0-1 (5 steps)] [particles: (live: 88839 | pool: 11161 | allocated: 100000)] Time: [startSim: 0.521s] [stepSim: 4.338s] [physics: 0s] [buildMesh: 0.0042s]
tyFlow002: [frames: 0-1 (5 steps)] [particles: (live: 88839 | pool: 11161 | allocated: 100000)] Time: [startSim: 0.526s] [stepSim: 4.377s] [physics: 0s] [buildMesh: 0.00345s]
tyFlow002: [frames: 1-2 (4 steps)] [particles: (live: 88839 | pool: 11161 | allocated: 100000)] Time: [startSim: 0s] [stepSim: 2.647s] [physics: 0s] [buildMesh: 0.00857s]
tyFlow002: [CACHE]: [frame: 1.84] [particleCount: 88839] Time: [buildMesh: 0.00276]
tyFlow002: [CACHE]: [frame: 1.00] [particleCount: 88839] Time: [buildMesh: 0.00269]

[super gnu]

I have sent a max file.. hopefully this is an easy fix.. both the resimulating, and the moblur of the mesh.

[super gnu]

quick update here, having spoken to the guys at cxhaos group, they suggested part of the "no motion blur" problem could be that tyflow is not passing on velocity information to the frost mesh.

[tyFlow]

Hey sorry, haven't been able to dig into this problem yet. Thanks for contacting CG in the meantime...I'll see if Frost ever queries me for the vectors (although my particle interface does return them by default). Hopefully we can get to the bottom of this soon.

[super gnu]

Hey sorry, haven't been able to dig into this problem yet. Thanks for contacting CG in the meantime...I'll see if Frost ever queries me for the vectors (although my particle interface does return them by default). Hopefully we can get to the bottom of this soon.

no worries Tyson.   as you say, hopefully it can be resolved, ive got everything working like a charm for my first actual live job using tyflow.. (go figure, i got asked to do my first animation requiring both cloth and particles in 20 years of 3d work, 1 day after tyflow came out... ive got 1.5 weeks till i have to render it. )

im on a steep learning curve having only dabbled with pflow in the past, but so far im extremely impressed.    

 just need some way to render a meshed particle system in NEXT gpu with motion blur, and ill be one happy camper.

[super gnu]

ok so some (small) progress.

exporting to prt then loading the file sequence into frost to mesh works, a bit.

now the velocity based motion blur works fine in next CPU, but next GPU renders a complete mess. it takes minutes and minutes building the moblur raycaster, then renders a complete blurred mess (also where particles are static) very very slowly.

so im guessing im looking at multiple issues.

tyflow -frost isnt bringing across the velocity info from tyflow

tyflow -prt-frost brings across the info, but frost doesnt like Next GPU.

im now trying to export frost mesh as an animated vrayproxy. last hope.!

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further update: so tyflow-prt-frost-vrayproxy finally gets me some vector motion blur in next GPU.

i need to render out a test tonight, but it seems some of the pieces are blurred in the wrong direction..

[tyFlow]

It's worth noting that VRay NEXT GPU has limited support for some features. The moblur artifacts you're experiencing could purely be a result of that. If VRay CPU renders the frost with moblur fine, then the actual problem may be in VRay GPU, not frost or tyFlow.