[tzs]

> Huh? The most basic skill of any driver is the ability to see if you're at a collision course with any other vehicle. I can accurately judge this at distances of at least 50 meters, and I'm likely vastly underestimating the distance. It is very apparent when this is the case. I can't tell if the distance between us is 45 vs 51 meters, but that is information with 0 relevance to anything.

That's probably because for things moving in straight lines at constant velocity you don't need to be able to measure distance at all accurately to figure out if they are on a collision course. You just need to be able to tell if the distance is decreasing.

First, you just have to note if their angular position is changing. If it is then they are not on a collision course.

If the angular position is not changing, then you have to check if the distance is decreasing. If it is they are on a collision course. If it is not then they aren't.

If you take advantage of the fact that cars generally have distinctly different front ends and back ends and that most of the time cars are traveling forward you don't even have to estimate distance. If the angular position is not changing just note if the direction the car is pointing has its front closer to you than its back or not. If its front is closer than its back then it is on a collision course. Otherwise not.

You will need to make some adjustments due to cars having volume. A near miss for point cars could still be a collision for cars with volume, but this should be fairly easy to deal with.