FXWars! Avalanche!: CoryC

#31

Waow, in many ways that’s the best test I’ve seen in this FXBattle, so far.

Comments:

  • In a still picture, you’ve really nailed the look of a real avalanche
  • Playing the movie though, the puffy clouds still look a bit like rising 2D sprites, and not a volumetric cloud
  • There are some issues with bouncing stones inside the cloud (they seem to flicker a little bit)
  • It looks like you applied some kind of physics, so when the avalanche particle drop and land hard, they release bigger puffs? That looks cool.
  • But most of all, this looks more like a snow avalanche than anything else we’ve seen here, because of those tumbling snow elements in the front of the avalanche, they’re awesome! :thumbsup:

Cheers,

  • Jonas
#32

Thanks Jonas,

on the comments:

1 - The still is just a frame of the video
2 - They are volume particles but because it is straight on with no shadows from the avalanche to the ground, it looks 2D yet. There is no easy and reliable way to get just a shadow pass of the particles. I think I have a way of doing it but that would require another pass and some playing around.
4 - The particles are released on the speed of the emitter so when it lands it slows down and more particles are released plus the bounce sends them floating higher for that look.
5 - thanks. I am glad to have have figured out how to do this right. I think the snow debris up front still rolls too far too fast yet but that is just a matter of increasing friction. Now to get those stones to look right and to get good shadowing.

#33

Here is that same test with the shadows added.

http://beta.usavgroup.com/cgtalk/aval/hilltest2.mov (873K)

#34

just wondering how long the render time is for most of the video/

#35

It is built in layers but I would guess overall there is an average of 30 seconds per frame or render time or 3 hours for the previous 2 clips.

#36

Very nice work!!!

But you should put on some turbulence on those hypervoxels. Now when they rising towards the sky they dont move and look unreal.

#37

yes I should. Thanks for reminding me. I noticed that yesterday but after staring at it for so long I forgot.

#38

Here you go Ztreem - http://beta.usavgroup.com/cgtalk/aval/hilltest3.mov (873K)

#39

That’s exactly what I meant when I said they look 2D - you just said it better than I did. :slight_smile:

And it looks MUCH better in the newest render, Cory!

-Jonas

#40

a one man effects team. a very impressive display, very realistic looking ( i think…no snow where i am) should be proud of what you have so far. definantly watching this one.

best of luck, doubt you’ll need it.

#41

that’s looking great. The only problem I have with it is that it doesn’t look like the clouds are settling back down. Right now it kind of looks like foam because the avalanche clouds grow and then stay there.

#42

The snow clouds don’t settle back down for quite a while (depending on the type of snow). One of my resource videos has an avalanche that has a snow cloud running at least 500 yards and the beginning still has snow that is a good 100 feet tall at least. It kind of just billows around like regular clouds in high speed.

Thanks Stallion and Jonas. We get snow here but no avalanches. I’ve shoveled enough of it to know I would rather watch it on the computer though.

#43

Yeah! Now it looks more like snow clouds. Very good work! :bounce: :thumbsup:

#44

Wow really coming along, really like the fracture shot…

#45

I had the same question. If that is indeed the case, shouldn’t there still be movement in the trailing clouds? It seems like it grows to a point and then freezes so, it seems unnatural.

It looks great BTW.

gl

#46

I’m not sure what you mean. The snow clouds are kicked up and then slow down and slowly (probably a couple of minutes at least) fall back to earth. There is always some turbulance but the snow clouds don’t continue to change size very quickly. That is how my last test was. They grow and then slowly shrink with some turbulent movement continuing.

I’d love to work on it more but I have run out of time that I can spend on the challenge so this is as far as I will get.

#47

that’s a shame you can’t finish… but if you do somehow find the time, maybe if you had the clouds thin out as they age it would look a little more realistic… and as they disapate they should grow as well… i haven’t seen you reference image but it just stands to reason that they will grow as they get older not shrink… and they will become more transparent as they grow… my 2 cents anyways.

#48

Here is a good link with a video that might help clear some of the confusion of what a real avalanche like I was working on should look like - http://www.nationalgeographic.com/ngkids/0301/. Remember, those snow clouds are made up of solid snow powder, not water vapor. They grow from the initial blast of wind and energy from hidden snow, ice, and debris then settle down slowly. They wouldn’t continue to expand due to gravity and a loss of the energy that created them. they wouldn’t thin because they are a solid mass slowly falling at a constant state. Physics alone say that it would take almost 4 seconds for the particles to return to earth from 200 feet and that doesn’t factor in the wind resistance that will keep them up a lot longer.

#49

Hey Cory, it’s a shame you won’t be able to finish this but good work on getting as far as you did! Hope you enter again in the next FX Challenge :thumbsup:

#50

check out the video on this sight http://juneaualaska.com/stories/avalanche/ if you think about it, snow is fine particles that are influenced by wind and gravity and such, so there will be drifting and disipation as the avalanche progreses, also, i would imagine that the great amount of friction caused by large amounts of snow moving very quickly would liquify some of the snow causing more of the expansion and disapation that i was talking about. as you will see in that video there are two visable layers in an avalanche there is the thick base full of debris and there is the cloud or “wash” that is carried off the surface and into the air, this cloud acts like any other gas, it drifts and expands and becomes less and less visable as it ages… anyhoo check out the vid, you will see what i mean