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ppk
11-19-2015, 12:53 PM
Evening All

I was so impressed with the spinning cubes at around 10 secs here:

https://www.youtube.com/watch?v=zPmH2iwHNS0

that I wanted to recreate the effect myself. I failed.

I created a cube, then used the array tool on them so they are all in one layer. In Layout I've set them to be a parts body resting on a base which is a static body. I then added a null and made it a vortex force. The vortex is affecting the cubes, but only the ones most distant, whereas the vortex (I'm guessing it's a vortex) in the video shuffles only 1the closest cubes around. Is there some way to reduce the field of influence of the vortex so it only affects the closest cubes?

I've attached the object and scene I'm using, if that's any help. I'm using Lightwave 2015.3.

Thanks for any help on this.

Paul131101131102

DrStrik9
11-19-2015, 01:24 PM
In the Item Properties for the vortex null, add a gradient ("T" button), using Input Parameter > Object Distance, and choose "vortex" for the object. This isn't perfect, and would require some tweaking, but it does go in the right direction.

I'll continue to play with it, to see what happens, because I'm working on similar stuff.

DrStrik9
11-19-2015, 01:40 PM
Another idea is to forget the gradient (or use it later to make strength adjustments along the vortex board) and just make the vortex null LARGER, like 10x as big ...

Nah, that doesn't really work. I'm making "some" progress, but it seems vortex, even with a gradient, is much stronger in the middle of its range than at either end.

--

I don't know if this is what you were going for, but I tweaked for awhile ...

First I moved the vortex null slightly outside the blocks on the X.

I ended up making a simple gradient with distance to the xortex-null, with an 11m range, then after calculating, placed the frame number at a relatively low point (like 16-17 out of 120), and very subtly added and moved gradient points, until I got the transition between the vortex-null end to the far end as smooth as possible, in an attempt to defeat vortex's super-strength in the middle of the gradient.

I'm attaching the altered scene: 131104

Oh yeah, with an optional turbulence. :+)

prometheus
11-19-2015, 02:37 PM
yeah a gradient..
but..analyze the vortex force...it is similar to that of a hurricane, meaning there is sort of the eye of the storm calm, thus there are more twist force at the rim of the vortex I think, so you got to set it to object distance..reference the null and have the white level at the start of the gradient, a value of 1 is a bit low, raise it to 2-5 perhaps.

spherical
11-19-2015, 03:21 PM
Actually, in a vortex the rotation is greatest at the center along the axis and decreases inversely to distance from it. A hurricane is a different mechanism.

DrStrik9
11-19-2015, 03:51 PM
Actually, in a vortex the rotation is greatest at the center along the axis and decreases inversely to distance from it. A hurricane is a different mechanism.

Well, not with LW Bullet vortex, in what I'm seeing (2015.3). And where do you find "hurricane" item type?

prometheus
11-19-2015, 04:42 PM
Actually, in a vortex the rotation is greatest at the center along the axis and decreases inversely to distance from it. A hurricane is a different mechanism.

Yes..you are correct, but you have to consider the vortex radius, if you have boxes by themself being 10 meter, and the vortex "greatest rotation" radius is smaller than that in the center..it wonīt affect much of the pieces in the center., thus I donīt think it effects the pieces very much, not to move them in any significant rotation around itīs original center anyway, itīs possible it may effect the center pieces own axis rotation..but not more than that.
But I think you are right..and I may have described it wrong, this description above is more what should be said, and this may explain why the center pieces are seemingly not affected that much as th outer pieces that is affected by a larger vector radius, the strenght doesnīt matter if the vector is to small, the amount of vortex angle donīt seem to matter either becuase of that.


Well, not with LW Bullet vortex, in what I'm seeing (2015.3). And where do you find "hurricane" item type?

There is none, donīt confuse my likeness to a hurricane to that of what is available as bullet forces.

Tips...you could try a forcefield too, and using the vectors..turn down the initial x,y,z values, use "T" textures..then you could actually try out fractals like coriolis, cyclone or whatever fractal type you want...it may take experimenting to get to understand the amount of force needed and scaling etc.
you can also mix those fractal noises with the initial state values of x,y,x ..if you set the blending mode to additive, as with this image..otherwise the pieces would just fly upwards without undulation/turbulence force.

There may be downsides to using fractals like ..it may be slower to compute, it may be the same as using fractals on old wind forces...extremly slow.

http://forums.newtek.com/attachment.php?attachmentid=131107&d=1447976574





131107

DrStrik9
11-19-2015, 10:34 PM
Yeah, I suspect Lino, or whoever did that little demo video, used multiple effects, including vortex. I like the Y vortex thing too! :+) And the texture really adds a nice touch.

ppk
11-20-2015, 03:06 AM
Another idea is to forget the gradient (or use it later to make strength adjustments along the vortex board) and just make the vortex null LARGER, like 10x as big ...

Nah, that doesn't really work. I'm making "some" progress, but it seems vortex, even with a gradient, is much stronger in the middle of its range than at either end.

--

I don't know if this is what you were going for, but I tweaked for awhile ...

First I moved the vortex null slightly outside the blocks on the X.

I ended up making a simple gradient with distance to the xortex-null, with an 11m range, then after calculating, placed the frame number at a relatively low point (like 16-17 out of 120), and very subtly added and moved gradient points, until I got the transition between the vortex-null end to the far end as smooth as possible, in an attempt to defeat vortex's super-strength in the middle of the gradient.

I'm attaching the altered scene: 131104

Oh yeah, with an optional turbulence. :+)

Hi DrStrik9

Thanks for taking the time to look at this. I think you might be on to something with the gradient > distance to object, but I haven't got anything like the demo yet! I'll keep tweaking.

Just going to the dentist but I'll keep trying later.

Ta!

lino.grandi
11-20-2015, 03:40 AM
Yeah, I suspect Lino, or whoever did that little demo video, used multiple effects, including vortex. I like the Y vortex thing too! :+) And the texture really adds a nice touch.

Yes, I've used more than one force at once in that scene. A Vortex and a Force Field pushing the bodies along the positive Y. The Force Field is parented to the Vortex. Both forces have a Gradient applied to the Strength, based on the distance from the Null/Force. When Distance = 0 the forces are expressing their maximum. When distance 2 meters, the applied force will be 0. The gradient of course make this act as a falloff.

Something to keep in mind when creating a new force, is that its Effect Type is set to Acceleration by default. If you want to get the same effect you see in my demo scene, be sure to set Effect Type to Force.

ppk
11-20-2015, 07:38 AM
Yes..you are correct, but you have to consider the vortex radius, if you have boxes by themself being 10 meter, and the vortex "greatest rotation" radius is smaller than that in the center..it wonīt affect much of the pieces in the center.

Yes, this is what I'm struggling with. The cubes further away from the vortex centre seem to be affected the most. Weird! And that's with a gradient that decreases the vortex's strength the further away from the vortex you get.

ppk
11-20-2015, 07:41 AM
Yes, I've used more than one force at once in that scene.

Sneaky! Great, thanks for the insight Lino. I'll try adding a Force Field as you describe and see what happens.

ppk
11-20-2015, 08:58 AM
Woo hoo! I've got the bare bones down now. I'll need to refine it a bit, but I think I'm headed in the right direction. I've attached what I've got so far.

Thanks for everyone's help (and your secrets Lino!).

131123

prometheus
11-20-2015, 01:46 PM
Yes, this is what I'm struggling with. The cubes further away from the vortex centre seem to be affected the most. Weird! And that's with a gradient that decreases the vortex's strength the further away from the vortex you get.

Not really that weird, if you stir cream in coffe with just by rotating the center axis and no big radius movent..you want see much happening, doesnt matter much how much strength or spin you do it with, you need the radius area of vector movement to be larger than the area it is suppose to affect I would say, maybe we could call it "event horizon"

ppk
11-21-2015, 04:13 AM
Here's the finished article. I'm really pleased with it.


https://www.youtube.com/watch?v=MKRhyFp7vCQ

ppk
11-21-2015, 04:15 AM
Not really that weird, if you stir cream in coffe with just by rotating the center axis and no big radius movent..you want see much happening, doesnt matter much how much strength or spin you do it with, you need the radius area of vector movement to be larger than the area it is suppose to affect I would say, maybe we could call it "event horizon"

When I added the Forcefield, it seemed to help the Vortex do what I wanted it to do.

prometheus
11-22-2015, 07:36 PM
When I added the Forcefield, it seemed to help the Vortex do what I wanted it to do.

we must define why, I would guess by adding forcefield, you actually push the pieces in some vector (unknown) and consequently it doesnīt stay in the center where the vortex radius isnīt large enough..by pushing it out from center with a forcefield, the vortex force radius will be more noticable.

ppk
11-23-2015, 08:25 AM
we must define why, I would guess by adding forcefield, you actually push the pieces in some vector (unknown) and consequently it doesnīt stay in the center where the vortex radius isnīt large enough..by pushing it out from center with a forcefield, the vortex force radius will be more noticable.

I initially thought that the Forcefield pushed the cubes off the ground, thereby reducing friction between them and the floor, and this made some difference... but I think your explanation probably holds more water.

Either way, this Bullet thing is fab. :)