View Full Version : Tron Light-Cycle trail effect. How do I do it?

09-28-2003, 05:46 AM
Hello, my names's John Von Ahlen, from Melbourne, Australia.

I'm hoping someone can help me out.

I am trying to get the effect of the tron light-cycles. Specifially the solid object trail left behind by the light-cycles.

My project uses arrows, and these need to leave a solid end trail as they move. I have tried lazy-points and trail plug-ins, but they don't give me the req'd look.

I am relatively new to LW, using V7, so if anyone out there can help me out, it would be appreciated.

[email protected]

09-28-2003, 06:00 AM
I'd model the trail and then use clip maps to hide what's not meant to be shown.

09-28-2003, 06:14 AM
i've got a trail happening (i created a spline in mod) but how do i use a clip map?
I got the model to follow the path of the spline, but the next step has me stumped...

like i said, i'm a bit of a newbie

09-28-2003, 08:02 AM
Take a look at the interview with Lightwolf over at NewTek Europe and download the files with the arrow from the Tour de France. This technique is ideal for such requirements and does not need any convoluted morphing or clip maps.


09-28-2003, 08:31 AM
thanks mylenium,

but i tried to find the interview and the only link was broken..

do you have the files or know an alternate site? tried google too..

09-28-2003, 12:06 PM
That's bad then ;-(. Unfortunately I haven't got the files handy. I will look at work if I have a backup of them.


09-28-2003, 01:17 PM
We had to temporarily remove the interview, but in essence Michael uses an arrow object with the tail cut into numerous sections - like about 300. He then assigns the Inertia displacement to the object and then draws out the head of the arrow to follow the path he's made. The end of the tail stays in place until it absolutely has to move because it's completely stretched out. Hope you get the gist of the idea...


09-30-2003, 06:45 PM
Dear Everyone,

Well, I figured it out! Actually, I found a thread from Celshader who showed how it was done, so I've modified it from her solution. She also showed how to change the surface properties to make it look extra cool.
If you type in "Akira-style Light Trails" you should find the thread.

I wanted to get the Tron Light-Cycle effect, but with trails that curved smoothly. The Tron LC's left trails there were sharp corners.

How it was done is this :

1. Create an arrow object, and cut the rectangular body section into 3000+ sections. I only wanted to cut on the Z-Axis, but couldnt find how to subdivide a polygon on only one axis (maybe someone could help me?!!)
So when the object curves it deforms smoothly.
Also important is to leave the ArrowHead as a seperate polygon, so that it doesnt deform.

2. Created a weight map on the body section and used a linear taper to have full strength on the bottom, and fade to 0 near the top, where the arrow head is. Remember to only apply a map to the body section, have the map taper off just under the ArrowHead.

3. In layout use the inertia plug-in (Object Properties/Deform) and assigned the weightmap that was created for the arrow object.

4. In the inertia plugin, I used the graph editor and created a curve for LagRate from 0.00 at Frame-0 and about 1.30 at Frame-30. Assign Bezier Spline Curves to the values to smooth things out. I had to play around with all the values to get it to look right.

5. Play around with the Lag Rate in Graph Editor. A higher lag will leave a longer trail, but if the object isnt divided sufficiently then there will be glitches on the path.

6. The actual animation I needed was 3D, as opposed to a planar 2D look, so I went into motion properties for the ArrowObject (press m) and under the Controllers and Limits tab, I assigned the Heading and Pitch Controllers to 'Align to Path'.
I also set a look-ahead value of about 0.065ms under the IK and Modifiers tab.

7. Sprinkle with salt and that's it!

Thanks to all for your help.


09-30-2003, 07:23 PM
>but couldnt find how to subdivide a polygon on only one axis (maybe someone could help me?!!)

hi, i like to use Multislice from N's Factory:
have fun.

10-02-2003, 08:41 PM
Dear Papou,

Thanks for the info and attachment.

In the meantime I just recreated a box polygon subdivided along the z-axis.
I'm going to check out the Multislice plug now!



facial deluxe
10-06-2003, 01:04 AM
Interesting way of doing this...

Have you tried Shift Spline Transform ?


10-09-2003, 11:57 AM
I picked it up at the store the other day... there's an interview about Tron 2. In it is a discussion about how Nvidia made special dual scan shader to get the light effects that glow.