tire marks across a screen

[Mike Clasby]

Here are two ways.

This seems kind of backwards, but you can make your tire tracks from the Effect Stroke (black) on a mask, you can make the “Car” layer move along the stroked path as the End % is animated. Here is Dan Ebberts paot asnwering a similar question:

https://forums.creativecow.net/cgi-bin/new_read_post.cgi?forumid=2&postid=856335

So on a new Solid Layer named “Stroke Layer” (Ctrl Y) draw the path that the car is to travel with the Pen tool. This is mask 1. Apply Render> Stroke, black, width your choice, and animate the End % with keyframes to make the stroke (tire tracks) move at the rate you want the car to move. Now select, then Copy the Mask Shape, then in the Car layer, click the position stop watch and Paste, that makes the car move along the Masks path.

Now Alt Click the Car’s Position Stopwatch and Paste this expression:

percent = thisComp.layer(“Stroke Layer”).effect(“Stroke”)(“End”);
valueAtTime(2*percent/100)

If you want to name your stroke layer Tire Track or something else, just change the “Stroke Layer” in the expression to the name you choose.

If you need two tire tracks Dup the Mask (select and Ctrl D), then dup the Stroke Effect (select and Ctrl D) and change the Path for the second Stoke to Mask 2. Double click the second mask and move it to where you like (like a PS transform).

You can also use the Write On effect to reveal a tire layer (if you want fancy tracks instead of skip marks), see this tut by Jayse Hansen for revealing fancy paths, it more complex than you need but the principal is the same:

https://forums.creativecow.net/cgi-bin/page_wrapper.cgi?forumid=2&page=https://www.creativecow.net/articles/hansen_jaysen/growing/index.html