Invertible Counterpoint Idea; 3 Voices.

Invertible Counterpoint Video:   • Invertible Counterpoint  
A melodic idea I had during a walk. Then I added a bass line and then added an alto line. Following the rules of counterpoint helps to compose away from an instrument, as I wrote this sitting down after my walk. Following rules of Invertible Counterpoint allowed me to flip the Bass and Soprano lines where now what was in the bass is now in the top line and what was the top line is now in the bass. I kept the middle lines the same. This is not supposed to sound amazing but it is supposed to showcase that this works. With this one can implement these ideas in their own music and make it more complex....
Some interesting modulations (key changes) happen in this short passage so pay attention.
Here are the modulations: C Maj to F#minor to F#Maj to BMaj to Bmin
They keys are being related to the Relative keys of the Major and minor versions of the keys.
C Major modulates to F# minor because A minor is C Major's Relative minor. A minor is relating to A Major which has F# minor as the Relative minor. F# minor relates to F# Major which performs a Perfect V-I Cadence from F# Major to B Major. B Major then relates to B minor.
The first line prepares you for the second line and without it the second line would be more random.