+ double RotationalPeriod() const noexcept;
+ /// day length relative to parent, not neccessarily a sun
+ /// gives absolute value in seconds
+ /// returns sidereal day for parent-less bodies
+ double DayLength() const noexcept;
+ double SphereOfInfluence() const noexcept;
+
+ math::Sphere CollisionBounds() const noexcept { return math::Sphere{ glm::dvec3(0.0), Radius() }; }
+ const glm::dmat4 &CollisionTransform() const noexcept { return local; }
+
+ const glm::dmat4 &LocalTransform() const noexcept { return local; }
+ const glm::dmat4 &InverseTransform() const noexcept { return inverse_local; }
+
+ const glm::dmat4 &ToParent() const noexcept { return inverse_orbital; }
+ const glm::dmat4 &FromParent() const noexcept { return orbital; }