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objuan
06-28-2018, 11:36 PM
I have some rough ideas how to go about this, but thought I'd post and see who has better ideas or tutorials on how to animate a tire deflating...

It has to be pretty detailed. Fully modeled treads on the tire, rotating as it goes down the road, nail goes in, and it continues to rotate as the bottom distorts and gets flatter.

Probably have to do a cross section version too, showing the various layers inside the tire.

Tips and thought appreciated as always.

jeric_synergy
06-29-2018, 01:40 AM
I think that's been covered here: try Searching on "tire bulge" or "tire flatten".

erikals
06-29-2018, 04:51 AM
maybe ?     >


https://www.youtube.com/watch?v=vxhIJ9ZQV8M

RPSchmidt
06-29-2018, 06:52 AM
I would do it as a morph animation, myself, but just because it would provide greater control. I could also create a puncture and tread loss with the morph if I wanted to, things that SoftFX wouldn't handle.

The SoftFX method is good, but then you have to worry about colliders and whatnot; it just seems like it would be easier to create a few morph states and use slider animations to get the effect.

That's just me, though.

mummyman
06-29-2018, 07:26 AM
Maybe bullet? There are some envelopes in bullet to change the pressure of the object. Would take some messing around... But ya.. morphs would have a lot more control

jeric_synergy
06-29-2018, 10:14 AM
I would do it as a morph animation, myself, but just because it would provide greater control. I could also create a puncture and tread loss with the morph if I wanted to, things that SoftFX wouldn't handle.
How would that work with the rotation??

I mean: are you "modeling in" the flat bit? How would that part not rotate w/the rest of the tyre?

raymondtrace
06-29-2018, 12:45 PM
One more option...

https://web.archive.org/web/20091216020851/http://www.3dtrainingonline.com:80/rigs.htm

jeric_synergy
06-29-2018, 01:43 PM
One more option...
https://web.archive.org/web/20091216020851/http://www.3dtrainingonline.com:80/rigs.htm
Yeahhhhhh, that doesn't work here. :( (2018: incompatible LWS maybe? It loads, but it don't 'work'.)
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How is that even supposed to work anyhow? (Gahd I loathe "CSI-ing" LW scenes: it's LOTS easier in c4d.)

gerry_g
06-29-2018, 02:45 PM
William Vaughan did a tutorial in LW8 where he used Soft Fx to flatten the base of a tire dynamically in layout, I can't find a streamable version on line but what it entailed was selecting your tire and applying the SoftFx plugin (which IS in LW2018) and setting up properties to deform it by using your ground plane or road to be the collision object and then calculating the results, is that any help

gerry_g
06-29-2018, 02:47 PM
yup jus saw the vid I was going to point too and just read the gotcha, so nothing to say

shrox
06-29-2018, 03:24 PM
Use a morph and rotate the textures, maybe attach them all to a reference object.

Greenlaw
06-29-2018, 03:29 PM
Years ago, I would do that by morphing through a gradient. If the gradient is based on height, you can set a range at the bottom part of the gradient and have the morph expand the tire through it. At the time, I was using a certain native plugin. I'll check what that was, but there are probably better ways to do this nowadays.

Greenlaw
06-29-2018, 03:34 PM
Found it. It's called Normal Displacement. Set the option to use Morph Map, and the Texture to Gradient. Then use the gradient as a mask for the morph. I'd whip up a quick example but a bit busy this afternoon.

BTW, you can create really a freaky body undulation fx with this tool too. Years ago, I used it that way in a Need For Speed commercial. The commercial was directed by John Landis so I boarded a sequence inspired by American Werewolf in London.

He asked me on set, "So, Dennis, what's the car doing here."

"Uh, the car is moving around like it's in pain."

"Dennis...cars don't feel pain."

"Um...it's moving like the werewolf in your movie?"

"Oh, okay. So you mean jerky and poppy. Got it."

He was great to work with. Funny but no nonsense when it came to work. Like, ok, let's get this done and move on. I liked that.

BTW, I haven't tried the tool in LW 2018 but what it's doing is pretty simple so I think it should still work.

raymondtrace
06-29-2018, 03:41 PM
Yeahhhhhh, that doesn't work here. :( (2018: incompatible LWS maybe? It loads, but it don't 'work'.)
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How is that even supposed to work anyhow? (Gahd I loathe "CSI-ing" LW scenes: it's LOTS easier in c4d.)

That's pretty.

This topic sort of aligns with the recent ink on paper discussion. Splinegod's scene uses a null with 3 displacement maps. One map to flatten the tire on the ground plane (positive texture value), one to bulge the tire on one side (positive texture value), and another to bulge on the the other side (negative texture value).

The scene loads nicely in LW7 with the null, but the null does not officially appear in 2015/2018. The 2018 screen shot has the tire moved up the Y axis but I can't figure out where the phantom null is that is deforming it.

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jeric_synergy
06-29-2018, 04:05 PM
The scene loads nicely in LW7 with the null, but the null does not officially appear in 2015/2018. The 2018 screen shot has the tire moved up the Y axis but I can't figure out where the phantom null is that is deforming it.

Raymond, i think the "phantom null" (good one! :thumbsup: ) is implicit in the LOCATION of the displacement map layers: there's 3 layers, and they're all just VALUES, with a non 0/0/0 location plus falloff. WORLD COORDINATES is on.

I still don't quite grok what it's doing, but that's OK, since it's not working anyway.

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Ugh!!! OKAY, this was OK back in the Amiga days, but nowadays this layout is B#LLSH#T:

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And "no, I don't WANT to use a null!!!".

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WORLD COORDS is on, I can't figure out why the disp seems to move w/the tyre.

BTW, is there an easy way to determine in LAYOUT what w.maps an Object has???

+++

FWIW, there IS a w.map associated w/this object: basically, the SIDES of the tyre are at 100%, and the center of the tread at 0%. BUT, I don't see it being used anywhere.
(Again, if this is working in LW7, obviously 2018 is missing some connection.)

RPSchmidt
07-02-2018, 06:58 AM
How would that work with the rotation??

I mean: are you "modeling in" the flat bit? How would that part not rotate w/the rest of the tyre?

I was thinking along the lines of creating your morphs and control their area of effect area using weight maps or gradients.

Another consideration could be using the SockMonkey approach, like in the documentation https://docs.lightwave3d.com/display/LW2018/Add+Object+Modifier

jeric_synergy
07-02-2018, 09:29 AM
I was thinking along the lines of creating your morphs and control their area of effect area using weight maps or gradients.

Just spit ballin' here: still not seeing how that would work, since w.maps are locked to specific vertices. Which brings up an interesting idea: "PROJECTING weight maps"? Am I missing an obvious, existing, way to do that? I think I may be. Any value that can be projected AND {picked up/read} nodally by the Displacement Editor, and used to modulate the Displacement? Interesting? Dumb? I'm not sure....

One idea that keeps coming up for me is the use of , ummm, "USE BONES FROM"? That feature that allows you to use another object's bones. For instance, in a non-steering tyre (ie the rear ones), a bone from the car body, set to STRETCH, could be placed in the appropriate place in the tyre. Since it's not the usual implicit child of the mesh, it would not rotate with the tyre. A combination of w.maps and range limits should restrict it to where it needs to affect.


Another consideration could be using the SockMonkey approach, like in the documentation https://docs.lightwave3d.com/display/LW2018/Add+Object+Modifier

I'll check that out.

(LATER): Wow, I thought SockMonkey was dropped years ago. Why don't people talk about it much? --It seems like it might accomplish much of what USE BONES FROM might do.

Let us all know. Esp. if you learn interesting stuff about SockMonkey.

RPSchmidt
07-02-2018, 09:59 AM
Just spit ballin' here: still not seeing how that would work, since w.maps are locked to specific vertices. Which brings up an interesting idea: "PROJECTING weight maps"? Am I missing an obvious, existing, way to do that? I think I may be. Any value that can be projected AND {picked up/read} nodally by the Displacement Editor, and used to modulate the Displacement? Interesting? Dumb? I'm not sure....

One idea that keeps coming up for me is the use of , ummm, "USE BONES FROM"? That feature that allows you to use another object's bones. For instance, in a non-steering tyre (ie the rear ones), a bone from the car body, set to STRETCH, could be placed in the appropriate place in the tyre. Since it's not the usual implicit child of the mesh, it would not rotate with the tyre. A combination of w.maps and range limits should restrict it to where it needs to affect.



I'll check that out.

I was thinking along the lines of controlling the location of the weight map using a null and the weight map value controls the amount of a given morph within the weight area.

So effectively, the tire has a weight map; the value is controlled by the null, perhaps distance to the tire, so that in that area of the tire closest to the null, the weight is 100 and tapers off; and the weight value controls the amount of morph in that area. The taper would be natural as the weight map value tapered off.

I'm spitballing too... haven't had the opportunity to test it at all, but it seems like it would be feasible. At a minimum, I thought that perhaps it could get ideas flowing for a solution.

jeric_synergy
07-02-2018, 10:06 AM
I think you've added an unnessesary step: just triggering the morph by proximity to the null should be enough, no? Of course, distance is radial....

RPSchmidt
07-02-2018, 10:51 AM
I think you've added an unnessesary step: just triggering the morph by proximity to the null should be enough, no? Of course, distance is radial....

True, just triggering the morph could be enough, but I was thinking of the blend between the separate "flattening" morphs and the morph effect in the area of the actual deflation.

So, for all of the tire, I have one morph active but in the area against the ground, I have another morph controlled by the weight map, with a more gradual blend into the first morph, if that makes sense.

That way, you could have several active morphs to get a more realistic result, and the portion controlled by the weight map would blend a little better with the other morphs.

On the distance, it would be distance on a single axis. Perhaps on the Y axis. Then you could place the null in the center of the tire, and make the tire its parent. The tire would control its rotation and position, but you could control the null on Y axis, moving it up or down for more or less flattening.

objuan
07-02-2018, 10:57 AM
Thanks for all the thoughts guys! If the client gives the go ahead, I'll dive in...

jeric_synergy
07-02-2018, 01:07 PM
On the distance, it would be distance on a single axis. Perhaps on the Y axis. Then you could place the null in the center of the tire, and make the tire its parent. The tire would control its rotation and position, but you could control the null on Y axis, moving it up or down for more or less flattening.
Possibly someone already caught this, but: if the null is the child of the tyre, {any/many} translation{s} away from the tyre's local origin will cause it to oscillate as the tyre rotates.

Rather than making it a child, you could constrain the null's position using, well, Constraints in the Motion Panel. It would match the tyre's Position, without inheriting its Rotation.