lerp method
Implementation
V3 lerp(V3 o, double amount) => _v3(
x + amount*(o.x - x),
y + amount*(o.y - y),
z + amount*(o.z - z),
);
V3 lerp(V3 o, double amount) => _v3(
x + amount*(o.x - x),
y + amount*(o.y - y),
z + amount*(o.z - z),
);