Pyroclastic smoke column

Started by Hannes, October 26, 2018, 05:32:18 am

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Matt

This is looking really awesome. Is the foreground rain and mist going the right direction, considering the rotation of the tornado?
Just because milk is white doesn't mean that clouds are made of milk.

Hannes

November 13, 2018, 05:01:13 am #61 Last Edit: November 13, 2018, 05:33:25 am by Hannes
Thanks!!!
Quote from: Matt on November 12, 2018, 06:37:12 pm
Is the foreground rain and mist going the right direction, considering the rotation of the tornado?


This is a good question. The answer is: I have no idea. Does the wind's direction have an influence on the direction of the twister's rotation?
Well, if only you'd asked me this question earlier, Matt! I just took a look at some tornado movies (which I did before), and now realised that all the tornadoes I've seen here are rotating counterclockwise.

Mine doesn't.

It's rotating clockwise.

That's typical: two possibilities, and I choose the wrong one. The notion of touching the twister's setup scares me. But (taking a deep breath) it's probably only setting (or removing) a "-" here and there.

...going to cry a little ...

Hannes

Thank god I found a website that saved my day!!!!

Quote:
"The direction in which a tornado twists depends a lot upon which hemisphere you're in. In general, most tornadoes in the northern hemisphere rotate cyclonically, or counter-clockwise. Only around five percent of tornadoes in the northern hemisphere rotate clockwise, or anti-cyclonically. In the southern hemisphere, however, most tornadoes rotate clockwise."

So, mine is either one of those rare ones that rotate clockwise, or it's placed in the southern hemisphere. It doesn't look like somewhere in the southern hemisphere, so I decided it's a rare one!!!

So far so good. But what about the direction of the wind? I guess, if most tornadoes in the northern hemisphere rotate counterclockwise doesn't mean, that the wind is always blowing in the same direction. So I'll defiantly leave the tornado and the wind as it is, since changing the wind's direction would look weird compared to the movement of the clouds, especially the distant ones, and I'll desperately take care of the animation of the closer bushes now, which is a tough one, since bending of objects in a population is another problem. I rotated the trees slightly on the X-axis to fake some swaying, but for small bushes this might look strange.

Dune


Hannes


Matt

I didn't mind the direction of the tornado itself (because it could be either hemisphere) - just the self consistency.

It's up to you ;D But here's my thinking. The tornado is the centre of a huge rotation of air. What would cause the strong winds in the foreground if they are not rotating with that vortex? If the foreground winds are moving contrary to the vortex, at what point between the camera and the tornado does the direction flip to be consistent with the tornado? There would have to be another powerful vortex at the midway point (not impossible, just very unlikely IMO).

Good idea to consider whether it would look strange against the movement of the clouds. But I think that is what tornados do - the front moves in the opposite direction to the back.
Just because milk is white doesn't mean that clouds are made of milk.

Jo Kariboo

Congratulations Hannes,your results are very impressive !!!

Hannes

Of course the wind in the foreground looks contrary to the rotation, but behind it it's moving wth it, so I'm not sure, what would be the right direction. It's tricky.

WAS

Would you be able to warp the rain/wind by a vortex following the path?

KlausK

HOW the hell do you do this!
It`s really amazing what can you do with TG.
Another thing is your (to me) quite short iteration cycles.
You sure know how to optimize the scenes.

Curious what`s next...

Cheers, Klaus

ps: if you ever want help rendering something - I`d be happy to assist.
/ ASUS WS Mainboard / Dual XEON E5-2640v3 / 64GB RAM / NVIDIA GeForce GTX 1070 TI / Win7 Ultimate

Oshyan

Some people seem to really just have this incredible ability to create and then iterate/improve quickly, especially (I think) with animation. DocCharley shows this as does Hannes. And it blows me away too, even knowing what I know of Terragen, and having seen 1000s of people using it over the years. These people are special if you ask me. :D

- Oshyan

Hannes

Wow, thank you all for your kind words!!!!!!!
I was offline for a few days (visiting relatives) and now found your nice comments.
I'm not sure about those (short??) iteration cycles. To me it feels like ages.... ;)

However I'm still working on it, and I'll show you the results as soon as possible.

Hannes

I have to say THANKS!!!!!!!!! to you, Matt, to point out, that the rotation direction looks weird somehow. I was so afraid of touching the setup, that I was hesitating to change anything.
But finally I did. It wasn't difficult at all. I only had to insert some "-"s and uncheck "reverse direction" in the vortex shaders. It was so easy, and in my latest tests I found that it looks so much more plausible. Initially I thought, that it may look weird if the rain was blowing from left to right and the clouds in the background move vice versa. But it's really working!!
In the meantime I animated the bushes, added an animated character and replaced the car by another one. I'll post it asap. You'll have to wait until my "short iteration cycle" is finished  ;). Gonna take a few days...

WAS

Quote from: Hannes on November 18, 2018, 06:14:20 am
I have to say THANKS!!!!!!!!! to you, Matt, to point out, that the rotation direction looks weird somehow. I was so afraid of touching the setup, that I was hesitating to change anything.
But finally I did. It wasn't difficult at all. I only had to insert some "-"s and uncheck "reverse direction" in the vortex shaders. It was so easy, and in my latest tests I found that it looks so much more plausible. Initially I thought, that it may look weird if the rain was blowing from left to right and the clouds in the background move vice versa. But it's really working!!
In the meantime I animated the bushes, added an animated character and replaced the car by another one. I'll post it asap. You'll have to wait until my "short iteration cycle" is finished  ;). Gonna take a few days...


Oh nice, I can't wait to see this. Glad you got it working, and wasn't a hassle.

Ariel DK

I almost missed this topic. outstanding work Hannes!
Hmmm, what version of Terragen does God use?