XParticle motion blur/ increasing render times Tweet

[London_Graeme]

Ok, I know this has been mentioned in the past, but this makes no sense.

I'm doing some particle work with XParticles, when I submit to render each successive frame time increases. I understand Octane IDs every particle, dead or alive, but this isn't down to increased particle numbers in the scene.

If I render frames 1 to 10, frame one might take a minute, but by the time it gets to frame 10 it's gone up to 3 minutes.

If I then stop the render and now set it to start at frame 10 - 20, then frame 10 which previously took 3 minutes, now takes one minute to render, and the render times with again start to creep up every frame. So about every 15 frames I stop the render, and begin it again from the last frame rendered.

[aoktar]

1-Version?
2-What happens if you use cached particles?
3-Don't use "Auto Detect" in RenderSettings/GeometryEngine, use "All movable".

If you still cannot solve that pls send me your scene to investigate!

[London_Graeme]

Hi Aoktar

I'm using C4D R18 and Octane V4 and the latest build of XP.

Everything is cached, am using "all moveable" . I did find another post about this and the explanation seemed to be that Octane kept all particle data in memory for the purpose of motion blur. So it kept going up. But if you stop rendering and submit from the last frame, the render time for that frame is about a third of the time it previously was.

The frustration for me is that the frame times go up and up, but if I stop the render after 15 frames or so, the render time for the frame/s goes back down, and creeps up as the render going on. So I'm rendering in 15 frame batches to render faster....

So basically if a frame is the tenth frame rendered, it takes substantially longer than if it were the first frame rendered.

[London_Graeme]

here's a screen shot ( hopefully ! )

You can see I stopped at frame 153 which took 1:36 s , I stopped the render and re-started and lo it now takes that frame 19 s !

[aoktar]

how do you use particles? render instances or direct access to emitter with object tag? How much is your emission rate/or particle counts?

[RyanSilva]

Please help!

I've seen this issue come up a few times in the C4d forum, but no solutions.

R20, V4.1-R2, Xparticles 4
Nvidia Quadro p5000 x 2 (16gb VRAM)
Windows 10 - Thread-ripper

Im having the exact same issue with motion blur and consistently increasing render times. Once you restart, it starts with a smaller render times but keeps increasing as before.

Xparticles water and foam simulation

188 frames (cached)
4 million particles

1 fluid Mesh - Octane object tag set to vertex speed, with vertex speeds created by xparticles mesher.
3 million(max) Foam Particles generated from Octane tag. Used sphere with 12 seg and added it to the geometry window.

Time Sampling = 1 frame
Geometry Control = All Objects Movable

With motion blur - Frame #87 15min
Without motion blur - Frame #87 20sec.

Am I running out of VRAM maybe? Or is it just all the foam particles and Octane's requirement of ID caching dead particles?

Thanks

[samprice]

Still having this issue in Octane 2020.1.3 - R20 and latest XP

Pretty much makes Octane unusable for a lot of x-particles work.

Have run in to this a number of times now. Looking like I will have to rebuild the scene in another render engine as there appears to be no solve? ;(

[aoktar]

Still having this issue in Octane 2020.1.3 - R20 and latest XP

Pretty much makes Octane unusable for a lot of x-particles work.

Have run in to this a number of times now. Looking like I will have to rebuild the scene in another render engine as there appears to be no solve? ;(

What's your issue? xpEmitter and motion blur or something else?
Please, make your reports more clear!

[samprice]

The increasing render times with each frame when using a cached xpEmitter and motion blur enabled.

Searching through more posts it sounds like this is a known issue.

Not entirely sure how I'm going to address this issue for my current project but may have to rebuild the scene using another engine.

Only other thing I can think of is to set a render queue with multiple files with a frame range of 10 frames each. Otherwise it starts to go from 1 min to over 10 minutes a frame after about 50 frames.

[aoktar]

The increasing render times with each frame when using a cached xpEmitter and motion blur enabled.

Searching through more posts it sounds like this is a known issue.

Not entirely sure how I'm going to address this issue for my current project but may have to rebuild the scene using another engine.

Only other thing I can think of is to set a render queue with multiple files with a frame range of 10 frames each. Otherwise it starts to go from 1 min to over 10 minutes a frame after about 50 frames.

Latest versions are refactored to work much better with xpEmitter and mblur. That's strange still having problems on you. Send me your scene so I can debug it