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daisukem
04-24-2008, 12:48 AM
Hello! I'm trying to optimize a scene with multiple fluids so each of them I turned its visibility off one frame before its start frame(fluid). So this helped the speed of processing, however all the fluids I had visibility off at start frame(timeline) did not render.. Please look at the image below to better understand hopefully.

- I have cached the fluids.
- they simulate fine.(playblasts are working fine but fluid2 and fluid3 in the below example are not rendered as if their visibility is off whole time.)

I wonder if this is a usual thing??
If my method does not work.. how would you work with a scene that has multiple heavy fluids..?
Do you cache then make them visible when it's needed?

http://img444.imageshack.us/img444/8441/fluidproblem1xo6.jpg

fedayi
04-25-2008, 06:15 AM
When you rendered the fluid1 - was the visiblity off the whole time?
Did you set up renders layers, so layer 1 was fluid 1, layer 2 fluid2 and so one? if yes, check your render layers, there might be an override or its not in the layer.


Can you better explain what you are trying to say, im having some trouble wrapping my brain around it.

Thanks

daisukem
04-25-2008, 07:12 AM
Sorry. I was rendering fluid 1,2,3 in one layer.

Since these fluids are heavy I decided to turn their visibility off when they are not in camera. Fluid 1 had its visibility on at start, and other 2 were off. I keyed the fluids visibility so that the other 2 fluids appear when they are needed.(I have cached the fluids.) For some reason, fluids 2 & 3 were not rendered..

I hope you understand my problem and have a solution. Thank you!

fedayi
04-25-2008, 06:01 PM
Double check your fluid container and the emmiters, you might have accidentaly, keyed the fluid container and the emmiters to off, keyed the fluid container to show visibility, while the emmiters were still keyed off. or vise versa, emitters are keyed on, but container isnt.

I suggest go into your outliner, and check all your containers and there emmiters to see what has been keyed and what hasent. This may take a little longer, but delete all of the keys on all objects (container and fluids) and re-key only the container, by doing it the long way by selecting in the outliner instead of the viewport. sometimes it happens to me when i drag select my container, i also select the emmiter if its in the way.

But what I can say, is that you should hide the containers instead, so when you are working on fluid1, hide the other 2, and work from there. only when your gonna render, then unhide all of the fluids and hit render.

from what i know about rendering, the computer isnt gonna render things that the camera doesnt see. so even if it is visible, if its not in front of the camera, its not gonna process.

hope that helps

daisukem
04-26-2008, 02:24 AM
Hi thanks. A little different question.. Say a fluid's start frame is 100, and you cache the fluids. But you only need to render it from frame120 to frame 150. Are you confident enough to render from 120 to 150 since it's cached? I'm kind of worried that it may misbehave if i ignore the first 20 frames.

fedayi
04-26-2008, 03:49 AM
you can choose how you want to cache your fluids.
you can choose the time slider, or start and end frame numbers that you provide.

if you can cached frame 100 - 150 then go ahead and render frames 120-150, since those frames are in cache it doesnt matter, since it will render out what has been cached.

the cache basically is like baking in animation and such. whatever has been cached on that frame, that is what you will see and render.

but here the deal, once its cached, its cached, if you make a change in the attributes like density and such, it wont show, you have to delete the cache and then re-cache it.

daisukem
04-26-2008, 06:42 AM
you can choose how you want to cache your fluids.
you can choose the time slider, or start and end frame numbers that you provide.

if you can cached frame 100 - 150 then go ahead and render frames 120-150, since those frames are in cache it doesnt matter, since it will render out what has been cached.

the cache basically is like baking in animation and such. whatever has been cached on that frame, that is what you will see and render.

but here the deal, once its cached, its cached, if you make a change in the attributes like density and such, it wont show, you have to delete the cache and then re-cache it.

cool thanks.

(ps)Looking forward to seeing your oil fire in motion! Looking good so far!

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04-26-2008, 06:42 AM
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