PDA

View Full Version : snow falling - i need help please!!



cbreton49
09-08-2008, 03:20 PM
I am trying to fall snow using emitters/hypervoxels with sprites. I can see them in vipor and in layout but when i render they are not there. Also, I can get them to fall for 20 frames but how do I keep them continuously for 7205 frames.
If anyone can help that would be great....

http://www.orloffconsulting.com/ftp_transfers/snowproblem.jpg

carol

cagey5
09-08-2008, 03:24 PM
Are they still missing if you render frame 5?

cbreton49
09-08-2008, 03:32 PM
I do have them rendering now, so my big problem is that once they fall from frame 1-20 there is no more snow. How do i keep them falling?
;o)

cbreton49
09-08-2008, 03:35 PM
forgot the picture:

http://www.orloffconsulting.com/ftp_transfers/snow.jpg

cagey5
09-08-2008, 03:36 PM
Well I don't have a great deal of experience with huge numbers of particles so I don't know what the practical limits are. The reason they are stopping is because you have a limit of 5000 being produced. You are also producing 1000 per frame, which is huge. After 5 frames you will only be seeing the residue of dying particles.

But as I say I don't know the practical limits for upping the particle limit

GregMalick
09-08-2008, 03:38 PM
Sounds like you've run out of particles.
Increase your particle limit.

Just looked at your pic.

You are generating 1,000 particles per frame and your particle limit is set to 5,000
therefore after 5 frames you have no more particles left to generate.

Those generated just settle due to gravity.

Ouch - cagey beat me to the answer.

cbreton49
09-08-2008, 03:38 PM
ok, so if i down the 1000 to 500 then up the 5000 to way more, it should do it longer? then I could move it per rendering each section.

JBT27
09-08-2008, 03:45 PM
ok, so if i down the 1000 to 500 then up the 5000 to way more, it should do it longer? then I could move it per rendering each section.

Yes.

Just do the simple math (which I guess you are figuring now) - how long your shot is, how many particles look good per second/frame, then multiply that by your shot length (frames or seconds) to get your minimum particle limit figure. Also make sure your particles live longer than they take to fall.

I don't know how many particles you need to look good for your snow, but if you have access to comp software, consider rendering several varied versions of your snow falling, with varying amounts of particles, then adjust the look in comp, which is always the way to go for full control.

In one-take, your particle limit looks like it needs to be in the millions. I've never gone that high, but suspect it will bog down way before hitting what you need, so look at other options, such as the comp route, if you can.

Julian.

cbreton49
09-08-2008, 03:53 PM
thanks so much, you've all been very helpful, it was just pointing it out to me and the brain finally registered how i had done it in the past...
thanks again