What's the difference between generative and transformative algorithms in relation to algorithmic composition of music?

As I understand the basic idea of the algorithms themselves, generative uses past candidate values (output becomes input) as progenitors (parents) for the next output, i.e. by combining them under certain conditions.

Transformative algorithms use environmental factors only to determine how to change the existing input.

However I've read that generative music as created by Brian Eno can use environmental factors and a single candidate input value, transforming it based on stored environmental factors.

I am struggling to understand what the difference is since there seems to be no universal agreement on what constitutes generative.