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vonpietro
04-22-2015, 05:01 PM
Hiya,

I'm in need of a decent fluttering flag that looks like this.
https://www.youtube.com/watch?v=4ufBoDdR6pM

I'm not sure how to keep that upper part connected to the pole stiff.

I'd like to make a fairly nice sim of it.
=)

found
xswamy did this one using bullet.
https://www.youtube.com/watch?v=a5UzeBQdE6E

is there any out there that has really high realism? I didnt see any on youtube.

finally
would sysflex be a better answer? albiet it a $200 answer.

tommyc
04-22-2015, 05:14 PM
Try this https://www.lightwave3d.com/learn/article/dynamics-creating-a-flag-blowing-in-the-wind/

djwaterman
04-22-2015, 05:35 PM
Honestly, check YouTube for a few Blender tutorials, follow them step by step and export the result as MDD to Lightwave. Quickest, realistic and you'll hardly play with the settings. Type in "Making a flag in Blender''.

vonpietro
04-22-2015, 05:40 PM
found this one
https://www.youtube.com/watch?v=GTPDbHXP9BU

pretty nifty - blender - i wasn't even thinking of using it. thanks

does exporting mdd mean simply saving it as fbx? or is it a different step?

mdd is on displacement tab?

jwiede
04-22-2015, 06:02 PM
would sysflex be a better answer? albiet it a $200 answer.

Yep, and highly recommend it for such needs. In fact, there's an example on the Syflex site of a sheet on clothesline drying in wind that shows how realistic Syflex can be (among other things) for such scenarios.

Neither Bullet nor ClothFx provide even near the quality of sim Syflex can provide for cloth-type scenarios, IMO. There's a compelling reason Syflex basically "owned" production cloth sims for ages.

MonroePoteet
04-22-2015, 10:44 PM
For a flying flag, ClothFX worked OK for me. Here's a sample scene. The flag is subpatched, and has two weight maps: Fixed (used in the ClothFX Fixed field), and TensionWeight used in the Weight field of the ClothFX. The Fixed weight map keeps it attached to the pole, and the diminishing weight along the X axis lets it flap more toward the end. Self-collision is enabled, and the flag pole is a Collision object.

You'll need to press the "Calculate" button in the FX tab of the flag object to see the effect.

The TensionWeight was created by creating a Z-axis UV map using Map=>New UV Map, flipping the U axis using Flip UVs, and then UV to Weight to create the weight map.

mTp

lightscape
04-22-2015, 11:01 PM
For a simple flag like this save the 200 bucks and use clothfx. Its more than capable.

vonpietro
04-22-2015, 11:17 PM
MonroePoteet

thank you very much, that saves me a bunch of time. Its a good stepping stone to get a subtle breeze version that i'm going for
=)
How would you say halve the speed?


I recall once calculated you can freeze, and then put it back on the object and then overcrank it to play back faster.
do you know how to do that?
i can't quite recall the steps, but i know you can do it.

MonroePoteet
04-22-2015, 11:28 PM
I'd recommend playing with the parameters of the Cloth, Wind and Grafity FX on the Flag object. For example, increasing the ClothFX Resistance to 100 and decreasing the Wind Power to 20% may give you the effect you want. Or more Viscosity on the Cloth and more Gravity. I don't know. You'll need to experiment to see what you want to get from it, and I can't answer that. Once you've got the parameters correct, you can bake the motion in the File => Save Motion so you get fast playback.

One thing I've learned about LW parameters in these cases: over-exaggeration is almost always good. Try radical changes in the parameters (e.g. Resistance from 5 to 100, Wind power from 200% to 20%) during experimentation to see large changes in the effect, and then fine-tune it to your requirements.

I don't know about slowing down or speeding up a baked motion file. I'd expect it's possible, but I don't know.

mTp

vonpietro
04-23-2015, 12:08 AM
ok

it's md reader, just load the saved motion and it allows you to set the speed of playback.
very useful feature. Saved me a bunch of times.

prometheus
04-23-2015, 02:58 AM
since there are no real obstacle interation in the flag, just go with clothfx ..should be quite realistic and easy doing, probably even bullet softbody.

Michael

zardoz
04-23-2015, 04:40 AM
can't you do this just with noise? I done a few flags for some ads and I used only two different noises (with different scales) combined and it worked fine

lino.grandi
04-23-2015, 04:47 AM
Had a try using Bullet in 2015.2.

The simulation is extremely fast, especially with self collision set to off.

prometheus
04-23-2015, 06:00 AM
can't you do this just with noise? I done a few flags for some ads and I used only two different noises (with different scales) combined and it worked fine


you could providing the flag is under constant (simulated) wind force..when a wind briefly stops for seconds..the flag will fall and interact with itself, in such cases a fractal noise displacement wouldnīt look realistic, otherwise it most certainly can, I think william vaughan has a tutorial on it..and quite easy to do if you find the right noise settings.

otherwise as Lino Grandi also mentioned, bullet should work too, a matter of finding some right tweaks in there too in weight and some other settings to avoid the rubber look that often is occouring with bulled softbody.

Michael

prometheus
04-23-2015, 06:03 AM
Had a try using Bullet in 2015.2.

The simulation is extremely fast, especially with self collision set to off.


Does that scene work with lw 11.6.3 ? I could try the 2015.01 discovery edition otherwise of course just to test it out.

tommyc
04-23-2015, 08:45 AM
It worked for me in 11.6.3.

vonpietro
04-23-2015, 08:56 AM
WI zardof OZ
you could do a displacement with any procedural or image map dragged through space. However, sim gives you the rippling effect that procedurally translating would never do right.
In essence you get a certain look, and while it may work for game graphics, it's not very realistic.

But it could be good for low wind situations in which you just need a flutter.

prometheus
04-23-2015, 03:46 PM
WI zardof OZ
you could do a displacement with any procedural or image map dragged through space. However, sim gives you the rippling effect that procedurally translating would never do right.
In essence you get a certain look, and while it may work for game graphics, it's not very realistic.




not sure...depends on wich procedural you use and how you animate it and also mix with other procedurals.

zardoz
04-23-2015, 03:54 PM
well it all depends on what you really need. of course a simulation is always better but I feel that I have more control with some noise displacing the flag

in these 2 examples I was asked to give the flag a bit of an 'epic' look so I thought that with noise it would be easier to control.
and I didn't need to have the flag dropping as if the wind was weaker so for these specific examples this worked fine.

https://vimeo.com/106183706
https://vimeo.com/118692094

vonpietro
04-23-2015, 04:02 PM
very nice work using procedurals.

looks like you used two scales - one for the overall s curve and one for the micro displacements in the s curve

which procedurals did you use?

zardoz
04-23-2015, 04:06 PM
well I don't have that here now, but I am pretty sure it was turbulence only for both...
and a gradient weight map in the flag to control where you want the displacement to happen

prometheus
04-24-2015, 07:40 AM
well it all depends on what you really need. of course a simulation is always better but I feel that I have more control with some noise displacing the flag

in these 2 examples I was asked to give the flag a bit of an 'epic' look so I thought that with noise it would be easier to control.
and I didn't need to have the flag dropping as if the wind was weaker so for these specific examples this worked fine.

https://vimeo.com/106183706

https://vimeo.com/118692094


Looks good and perfectly accepted, and that is what I ment that procedural noise can be sufficient if it is supposed to look like a flag under constant wind force, fitīs nicely on longer banners too, a flag that is under very varied wind force and wind stopping and then picking up again, usually it folds over itself a little and in such case..try dynamics.

zardoz
04-24-2015, 07:53 AM
yeah I agree with you. If I needed to have the flag dropping because of lack of wind or some other random stuff it would be complicated to do

Surrealist.
04-25-2015, 01:52 PM
My contribution. Another scene to study. :)

vonpietro
04-27-2015, 04:34 PM
I Just wanted to say thanks for all the helpful files.