Factorio Prototype DocsVersion 2.0.15

A number between 0 and 1 (inclusive) representing the distance from the upper end of the leg (0) to the lower end of the leg (1) where the effects will be triggered. For the upper leg, position 0 represents the point that the leg connects to the entity's hip and position 1 represents the knee. For the lower leg, position 0 represents the knee and position 1 represents the foot.