Question by mwitt8178 · Jun 02, 2014 at 08:03 PM · transform lerp path waypoints bezier

Determine transform.position of location between two waypoints on bezier path

Thanks in advance for your assistance.

I am currently using Unity's "Lerp" functionality to determine a specific transform.position between two waypoints on a straight path using distance.

I was wondering if there was a similar approach to determining the transform.position of a specific location between two waypoints on a bezier (curved) path using distance.

After much research and googling, I cannot seem to determine a "best practice" approach to solving this requirement. If someone can point me in the right direction, I would be greatly appreciative.

Thanks again!

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Graham-Dunnett ♦♦ · Jun 02, 2014 at 10:12 PM 0

A lot depends on how close the bezier curve is to a straight line. If it's close to the straight line between the two end points, just use a lerp (so you get zero at the first point, and one at the second) and feed that into the bezier curve to get the position along the curve. If the curve varies greatly, then this lerping won't be accurate enough. In which case you're going to need to do some velocity based calculations to work your way along the bezier path. In essence you're assuming the velocity along the curve is constant, so you need to compute how long the curve is. Then, you can work out how far along the curve you get in a fixed amount of time. Maybe you can approximate this by computing 10 points along the curve and sampling their position, and then measure the distance between these sample points. You then have an approximation to the length of the curve. Hence you know how long it might take to travel along the curve at a fixed speed.