How do you go about making tracks in the dirt from a tank and or car tires?

In an animation or a still image?

Good question...

I want to do this for animation, I have some tanks that I want to try it out on....

This not an easy task but it can be done. Like most things in 3D animation, this will require deliberate, planned choreography. You'll actually need to create an animated texture map of progressive tread tracks in a 2D program that supports animation (Painter, Adobe Photoshop CS3, Apple Motion) This completed animation file will then need to be imported into the color and bump channels as a mixer control for the ground texture map or placed into the displacement channel. If it goes into the displacement channel, expect a significant speed penalty during render. You've got some "wiggle" room or error room available during the Carrara motion because the tank can hide a portion of the tread animation so it doesn't need to be super precise. However, the tracks will need to be perfectly spaced in their side-by-side relationship. If you choose to put the animated map in the displacement portion of the texture, you will have very, very little room for error. If you're doing a single tank, there is a way to progressively swap one ground texture for another so you could actually "paint" the ground texture, one with treads, one without, and then progressively exchange them as the tank moved across the scene. Professionally, things like this are often disguised by dust clouds in post production or carefully planned camera moves the severely limit the time "on screen" of the ground. That way precision becomes less of an issue. I see the treads as being a challenge too. ;) Mark

Hmmm., are there any animated files out there!!

I don't suppose you can animate a matching boolean assemblage? I actually have not tried booleaning in Carrara, though it was the only way I could build some things in Bryce. Could you boolean a solid terrain with an invisible object, say a negative duplicate of the tire pattern, or tread segments? A boned matching negative track assemblage that unrolls behind a tank leaving booleaned tread marks might work. It would not be that hard to synchronise the timing of the two mechanisms.Anyway, if it could be done, it would probably render as slowly as using a displacement animation. It would probably be easiest and fastest to achieve this effect using material channels, as Mark said.

"Any animated files out there?" Not that I'm aware of. Carrara doesn't support animated booleans. Additionally, the booleans in Bryce are actually "pretend" booleans because the geometry is still there, just hidden. In Carrara, it actually removes the geometry. I'm still looking for the one-program-does-all solution. Of course you know what the ultimate 3D program is? Reality. ;)

Lol, no complaints from me about limitations in Carrara. I think you can do just about anything in Carrara if you have a will and a bit of cleverness.

I have worked on a deformer plugin that does this very thing for use with tanks and vehicles as well as human feet.  There is an existing plugin for Carrara 5 from Akuro Digital called the 'potentializer' that can be used to do it (sorry, cant easily find the link for that).  Mine allows for variable size 'feet' that deform a terrain or vertex object and I added a matching shader for the disturbed earth - but that part didnt work on large terrains.  My plugin will work well for close ups if I subdivide a spot area but for large terrains its slow and to add detail like tank track imprints it would need a lot of polygon detail or detail in the path of the vehicle.

The beauty of a plugin like this is that you apply my deformer to the terrain, select which objects are 'feet' then when you animate or render it builds up the changes frame by frame in a copy of the terrain or vertex object.  Change the path of the vehicle and the tracks left behind are reset.

Its still a beta version though and after working on the Jiggle Deformer I've found out how to do it so it works much much quicker and so I need to revise the code. 

The beta works though, I used this on an animation of an excavator you can see in my website gallery.  Look closely and you will see that it leaves a rut behind it.  For digging the hole I made a morph and for scooping and dropping the earth I couldnt use physics and had to do it manually...which sucked.

And I did another test using the ATV from Daz leaving a trail in the sand which is much more clear - it also uses a terrain following plugin I've been working on but havent perfected yet.

Reply to me directly if you are interested in the trying out the current beta for C5-6 (windows only) if this is what you are after.

Jeremy
www.Sparrowhawke3D.com

Wow Sparrowhawke! That sounds like a fantastic plug-in!  It would sure make it lot easier to achieve the effect Mhscspo was looking for.

Attached Link: http://www.kawachi.zaq.ne.jp/kurozuka/akurodigital/potentializer.html

> Quote - I have worked on a deformer plugin that does this very thing for use with tanks and vehicles as well as human feet.  There is an existing plugin for Carrara 5 from Akuro Digital called the 'potentializer' that can be used to do it (sorry, cant easily find the link for that).  Mine allows for variable size 'feet' that deform a terrain or vertex object and I added a matching shader for the disturbed earth - but that part didnt work on large terrains.  My plugin will work well for close ups if I subdivide a spot area but for large terrains its slow and to add detail like tank track imprints it would need a lot of polygon detail or detail in the path of the vehicle. > > The beauty of a plugin like this is that you apply my deformer to the terrain, select which objects are 'feet' then when you animate or render it builds up the changes frame by frame in a copy of the terrain or vertex object.  Change the path of the vehicle and the tracks left behind are reset. > > Its still a beta version though and after working on the Jiggle Deformer I've found out how to do it so it works much much quicker and so I need to revise the code.  > > The beta works though, I used this on an animation of an excavator you can see in [my website gallery](http://sparrowhawke3d.com/Videos/Excavator.mov).  Look closely and you will see that it leaves a rut behind it.  For digging the hole I made a morph and for scooping and dropping the earth I couldnt use physics and had to do it manually...which sucked. > > And I did another test using the [ATV from Daz](http://sparrowhawke3d.com/Videos/FootprintsTest.avi) leaving a trail in the sand which is much more clear - it also uses a terrain following plugin I've been working on but havent perfected yet. > > Reply to me directly if you are interested in the trying out the current beta for C5-6 (windows only) if this is what you are after. > > Jeremy > www.Sparrowhawke3D.com

Try this link..

Wow! Crazy plugin as always! I really dont know how the pugin works, but in most works a bump map can do the job of creating the trails, can have this option in your plugin?

hey SparrowHawnke, dont want to transpose a simple  Lightwave script for Carrara? Its a script that create a simple 3 lights rig based in the scene dimension... like a studio light set.

GKDantas,

My deformer does build up an internal texture map which a linked shader can use to get a depth value.  I didnt perfect this feature though and it didnt work for large terrains.  

Most games use decals for bullet holes and footprints.  The idea of using the collision of objects with a terrain to paint a detailed bump map is interesting.  That sounds more like the kind of thing Eric at the DCG could do. 

(For your other off-topic idea send me any requests directly and I'll see what I can do.  Modifiers are my speciality though.)