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evolross
07-12-2007, 09:01 AM
I have a fairly simple four-wheeled vehicle object that I want to travel along rolling terrain that has enough polygons in it for it to be smooth. As I animate and key the X and Z axes on the vehicle it traverses the terrain, however it penetrates through the ground as the elevation goes up and down. Is there a way to not have to key the vehicle in the Y axis and make it rest on the terrain on it's wheels?

As this point, the tires do not need to move independently based on rocky terrain because the terrain is smooth and the camera is far away enough that it isn't an issue.

I tried using dynamics by setting the ground object as an FX Collision Object and the vehicle as a HardFX Object and using "Stick" and this works until my X and Z keys turn the vehicle in a new direction. Once a collision has happened, the vehicle stays on it's path as defined by its momentum and doesn't turn.

I basically want to only key X and Z and just watch the vehicle pivot and travel along the Y axis appropriately according to the rolls in the terrain.

SplineGod
07-12-2007, 09:34 AM
try the sticky plugin.

evolross
07-12-2007, 11:24 AM
try the sticky plugin.

That worked, but now I'm trying to get it's pitch rotation to rotate with the terrain. Right now it's static. My pivot point, which is what sticky uses, is on the back set of tires.

So the front set of tires is still either penetrating the terrain (when going uphill) or hovering above the terrain (when going downhill). Can this be automated too?

SplineGod
07-13-2007, 09:27 AM
You also might want to try this plugin:
http://www.andynicholas.com/thezone/index.php?area=getfile&app=LW&file=1

evolross
07-16-2007, 02:10 PM
The Vertigo plugin looks really nice. It's annoying that it's this hard to natively animate a vehicle and it's tires appropriately in Lightwave.

I tried using Sticky, and it works, but not the way I need it to. I tried applying Sticky to each one of the four tires, and that works, but then you can't parent the tires underneath the chassis, Sticky freaks out and does strange things. Anything that has Sticky applied to it, doesn't seem to like being being a child to anything.

And it doesn't seem to do any good if a Sticky'd Null is the parent of the tires. The Null obeys the Sticky rules, and even with Align to Path Heading and Align To Path Pitch, the tires still subtly break the surface and float above the surface. :stumped:

SplineGod
07-16-2007, 03:17 PM
Try making the tires part of an IK chain for the suspension.
At least vertigo allows you to do it easily. Theres always the option of messing with the dynamics. :)

Mr Rid
07-16-2007, 08:26 PM
Am reminded of the little known motion modifier, Texture Motion. It may not help at all in your situation but have used it for keeping wheels strictly against rough terrain. It's only works if your terrain is derived from a displacement map, which I always try to do since it can make modifying easier. I started using it once to reference null Point and Orientation constraints to rock a vehicle as if with suspension.
(examples attached)

Mr Rid
07-16-2007, 08:28 PM
Doh! Try these-
http://www.box.net/shared/static/pu1phipxid.mov
http://www.box.net/shared/static/669z7oziqk.mov

Surrealist.
07-17-2007, 03:47 PM
The Vertigo plugin looks really nice. It's annoying that it's this hard to natively animate a vehicle and it's tires appropriately in Lightwave.

I tried using Sticky, and it works, but not the way I need it to. I tried applying Sticky to each one of the four tires, and that works, but then you can't parent the tires underneath the chassis, Sticky freaks out and does strange things. Anything that has Sticky applied to it, doesn't seem to like being being a child to anything.

And it doesn't seem to do any good if a Sticky'd Null is the parent of the tires. The Null obeys the Sticky rules, and even with Align to Path Heading and Align To Path Pitch, the tires still subtly break the surface and float above the surface. :stumped:

I had the same issue with sticky. There was a thread on this a while about using textured motion as mentioned above. You might try a search for that as well.

Surrealist.
07-17-2007, 03:48 PM
Doh! Try these-
http://www.box.net/shared/static/pu1phipxid.mov
http://www.box.net/shared/static/669z7oziqk.mov

Very cool!

Mr Rid
07-17-2007, 04:46 PM
...It's annoying that it's this hard to natively animate a vehicle and it's tires appropriately in Lightwave.

...I tried applying Sticky to each one of the four tires, and that works, but then you can't parent the tires underneath the chassis, Sticky freaks out and does strange things. Anything that has Sticky applied to it, doesn't seem to like being being a child to anything.

And it doesn't seem to do any good if a Sticky'd Null is the parent of the tires. The Null obeys the Sticky rules, and even with Align to Path Heading and Align To Path Pitch, the tires still subtly break the surface and float above the surface. :stumped:

Ah, yes, Lightwave. 60% there.

Sekhar
07-17-2007, 05:05 PM
Doh! Try these-
http://www.box.net/shared/static/pu1phipxid.mov
http://www.box.net/shared/static/669z7oziqk.mov
There videos are great! I need to move a car on a mountain road (Vue landscape) for a short film and have been struggling with sticky too.

I wonder if you could create a texture map reflecting the depth (say with gradient based on the Y value) and then use that for textured motion... Does that make sense?

Mr Rid
07-17-2007, 08:13 PM
There videos are great! I need to move a car on a mountain road (Vue landscape) for a short film and have been struggling with sticky too.

I wonder if you could create a texture map reflecting the depth (say with gradient based on the Y value) and then use that for textured motion... Does that make sense?

Yes, you can do that. I once made a heaving ocean in LW that someone needed in Maya to add particle spray to but it would not convert correctly. So I made the ocean 100% luminous and applied a vertical black to white gradient on the X. Positioned the camera looking down on the Y with a very long lens (now you can use orthographic), framed the ocean object exactly, and rendered this out as an animated displacement map for the Maya ocean mesh. It worked very well for that situation. But I imagine there may be some little things to workout for the Texture Motion to work right.

Cageman
08-31-2007, 02:22 PM
Cool thread!

Anyone got any ideas how to approach a moving surface; both displacements as well as dynamics? Like, a boat on a very turbulent moving ocean. Any ideas would be great! I've tried Sticky, but even if the object is in Worldspace, it does have alot of problems and if I bake the results all gets really funky! Vertigo doesn't seem to work with animated surfaces. :/

SplineGod
09-01-2007, 01:22 AM
cageman,
Alot is possible with the standard LW tools.
I show some techniques in my Displacements and Endomorphs 2 DVD to do this quite easily.
Heres an example of an ocean surface being drivin by displacements. The ship is reacting to the waves.
http://www.3dtrainingonline.com/examples/ship.mov

Cageman
09-01-2007, 03:43 AM
SplineGod, I know how to get an object moving over a displaced mesh using texture motion modifier, but now I'm heavily dependent on dynamics as well. Since I have access to Maya and PointOven, I'll bake an MDD of the deformed water and bring it into Maya to see if Geometry constrain will work.

SplineGod
09-01-2007, 03:52 AM
This isnt using the textured motion modifier. This is using a combination of displacements and dynamics. The ship is actually moving based on the average of the displacement being placed upon it rather then the ships pivot point being displaced.

Cageman
09-01-2007, 05:57 AM
Ok... well here is the problem. I've got an ocean which is mostly displaced by dynamics, not displacements, but Cloth Dynamics. Ok, so what I want to do is to have an object following the surface even if I also animate it in whatever direction I want. This is very easy to do when using Displacements, because their nature is textures. But when using ClothFX deforming an object, and you want an object to follow the Cloth-object when it is moving itself, you are out of luck in LightWave.

Cageman
09-01-2007, 06:09 AM
*Doublepost*

toby
09-03-2007, 05:23 PM
Ok... well here is the problem. I've got an ocean which is mostly displaced by dynamics, not displacements, but Cloth Dynamics. Ok, so what I want to do is to have an object following the surface even if I also animate it in whatever direction I want. This is very easy to do when using Displacements, because their nature is textures. But when using ClothFX deforming an object, and you want an object to follow the Cloth-object when it is moving itself, you are out of luck in LightWave.
Easy-peasy!
Texture the cloth with a b&w gradient, from the highest point/white to the lowest point/black (planar projection from the side). Render a sequence from top view. That's your Textured Filter map.

Cageman
09-04-2007, 02:40 PM
Easy-peasy!
Texture the cloth with a b&w gradient, from the highest point/white to the lowest point/black (planar projection from the side). Render a sequence from top view. That's your Textured Filter map.

Oh man! Never thought of that! Haha... "Can't see the forest because of all the trees".. :) Now that you say it, it's quite obvious! (have to try it though) :)

I also noticed that it is possible to bake Sticky. Just make a clone, remove sticky from the clone, apply Relativity and make it follow the Sticky object. Now you can bake the result to the clone. However, Sticky has some strange behaviour, jumping around all the place when scrubbing the timeline.

Mr Rid
09-04-2007, 03:19 PM
Oh man! Never thought of that! Haha... "Can't see the forest because of all the trees".. :) Now that you say it, it's quite obvious! (have to try it though) :)

Er, this was in the post just before your first one.

toby
09-05-2007, 10:10 AM
Er, this was in the post just before your first one.
Doh!

Cageman
09-05-2007, 10:29 AM
Er, this was in the post just before your first one.

Wops! :) Well, I must have totaly missed your post Mr.Rid.. sorry about that! Either way, I can easily bring the deformed mesh into Maya and use Geometry Constrain to get what I want. But I really want to learn how to solve this in LW by itslef so.. :)

A good trick is worth repeating, don't you think? ;)

evolross
10-22-2007, 03:50 PM
However, Sticky has some strange behaviour, jumping around all the place when scrubbing the timeline.

It seems like Sticky only works right when the Sticky object has only a start and ending translation key where you're trying to get it to stick. For example, if you're moving a Sticky object across the surface of a StickySurface sphere, Sticky behaves as expected when the object moves between two keys. If you use several keys to keep the object near the surface of the sphere, it jerks and juts when it hits its keys. The weird alternative is to try to use the graph editor to bezier-spline key the motion of the small object around or near the sphere's surface, only using a start and end key. This sucks because you then can't control speed because of only having a start and end key. And keeping the object on the StickySurface is what Sticky is supposed to be doing anyway! But you end up doing it with bezier-spline keys. You have to get it roughly close and Sticky does the fine tuning.

The thing that would make it all work right would be if the Sticky object would actually stick to the surface once it hits it, no matter where its future translation keys tell it to go. Try to get to the translations keys as best possible, while STICKING to the mesh. But only when your keys/curves have the Sticky object moving very very close to the StickySurface, will it work. If you're not close, your Sticky object will pass right through the mesh.

:stumped: