Todas las teclas definidas en la curva de animación.
This lets you clear, add or remove any keys from the array.
If keys are not sorted by time, they will be automatically sorted on assignment.
Note that the array is "by value", i.e. getting keys returns a copy of all keys
and setting keys copies them into the curve.
Mirar también: Funciones Keyframe struct, AddKey, RemoveKey.