public Vector2f interpolateLocal(Vector2f finalVec, float changeAmount) {
        this.x = (1 - changeAmount) * this.x + changeAmount * finalVec.x;
        this.y = (1 - changeAmount) * this.y + changeAmount * finalVec.y;
        return this;
    }
Interpolates linearly between the current instance and the specified
vector, returning the (modified) current instance.

<p>this = (1 - changeAmount) * this + changeAmount * finalVec

@param finalVec the desired value when changeAmount=1 (not null,
    unaffected unless it's {@code this})
@param changeAmount the fractional change amount
@return the (modified) current instance (for chaining)
jme3-core/src/main/java/com/jme3/math/Vector2f.java