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ganzo
01-09-2011, 06:41 PM
Hi guys,
Working on getting fire on a character. I'm emitting from surface and am also using fields to drag the fluid when the character moves, but I also want the fluid to collide with characters body and not go through it. However when I make that mesh collide with fluid all fluid gets trapped inside since the emission is from surface. I try setting min-max distance, but when I play...it takes forever and have to kill maya. How does one make the fluid collide successfully with the same mesh that is emitting the fluid?

Here is the link:
http://vimeo.com/18583420

Derek Wolfe
01-10-2011, 08:53 PM
In general fluid collisions do not work well with animated meshes.
Perhaps try to oversample the fluid to see if you get better results.

pixelranger
01-10-2011, 09:04 PM
Or add a "chest plate" object just inside the chest surface and wrap deform it to the character. And make the chest plate collide. Also put a low res "face" mesh just inside his face. And maybe a couple other parts that you want to have collide with the flames. And then make those meshes collision objects.

nice flames, btw.

BillyTheKid123
01-10-2011, 10:58 PM
Or u could just duplicate the mesh and have it emit only speed (replace) with an inherit velocity of 1 and 0 normal speed. With 2011 of course

ganzo
01-10-2011, 11:41 PM
Perhaps try to oversample the fluid to see if you get better results.
Actually I'm already oversampling it, but some density still got stuck inside the mesh since it emits from the surface...such surface might be in the middle of a voxel....so half of the fluid does manage to be on the outer part of the mesh and some is inside. So tried max distance...and that somehow kills maya.

Or add a "chest plate" object just inside the chest surface and wrap deform it to the character. And make the chest plate collide.

Yeah I had a feeling I would have to do this...just did not want to approach this method because it is quite tedious since I want collision on every part of his body. I actually followed this approach with the drag fields..basically made a skeleton out of them through the whole body....still missing some parts though. I guess this might be the standard way of doing things if you want to go for accuracy...I'll start right away and make some quick tests...thanks!

Or u could just duplicate the mesh and have it emit only speed (replace) with an inherit velocity of 1 and 0 normal speed. With 2011 of course

I actually recently migrated to 2011 from 2009...did not know about this speed emission. Where exactly is this located? I'm just familiar with typical density, heat, temp emission....never knew about speed. I'll research this and see what this is all about...thanks for the tip.

I'm still missing smoke and embers that I want to add...but aside from that...what else could I improve on what I have posted?

Thanks guys

Aikiman
01-11-2011, 12:37 AM
I like it, maybe you could tweak the shader a little bit add some hot spots here and there and if you have the patience, add a SOuP's uprezFluid node to increase the resolution.

To be honest, do you really need collisions?

Apart from that it looks great.

BillyTheKid123
01-11-2011, 01:04 AM
Speed emission is on the emitter itself at the bottom. It's off by default. Hopefully your container is at the origin. If it isn't, you will have to use auto resize ( to emitter checked on) and have the box start at the origin and snap to the your surface emitter once it runs. ( a 2011 bug)

ganzo
01-11-2011, 07:44 PM
I like it, maybe you could tweak the shader a little bit add some hot spots here and there and if you have the patience, add a SOuP's uprezFluid node to increase the resolution.

To be honest, do you really need collisions?

Well from what I see...most of the body interaction is fine with just drag fields I have added...except for the torso...when the creature takes a step forward you do see that the flames go into his body, that is something I want to prevent. Fast moving objects would put out the flames on the front...or rather...the flames would be pushed to the sides and to the back. That's sort of what I want.

Its a funny thing with fire....if you add too much rez...it actually starts looking worse. The max I have on one axis is 180 I think...after that...the fire gets too much detail that it actually starts looking noisy and grainy....which works great if you are doing smoke, but don't know..on a personal level I don't like going too high on rez for fire projects, haha for smoke I just crank the thing as high as it will go.

About SOuPs nodes...I've seen them but never actually tested any of them. I'll check them out. Thanks a lot!

Speed emission is on the emitter itself at the bottom....
Thanks for the tip...I think I'll have to R&D all of this on the side since I'm still not too familiar with all these settings, just reading your description seems that many changes are needed on my container, maybe it really is not much...but well...I'll have to test all this out to see pros and cons....thank dude.

Aikiman
01-11-2011, 08:00 PM
You are right, too much detail can spoil fire, I guess its sometimes hard to tell exactly what you have from a compressed/degraded video on youTube. If you dont need the detail then forget it.

Speed emission is really easy to setup its just a matter of turning it on! and will give you some nice motion effects inside the container, it may even fix your problem and it will definately be quicker to sim than using collisions.

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