I have a theory on how the 3 eyes relate. "My theory is this in the beginning the Byakugan (white eye or empty eye) was the original. That was Kaguya's ORGINAL power upon getting chakra however the power of the biju turned the eye blood red like those of an enraged jinchuriki hosts eye. The empty eyes were filled with the marking of the Shinju's eye's. Because the new eye is not clear it lacks the sheer perceptive power of the original. but in turn it is filled with new powers. That is shariinegan. The rinnegan is an eye that is given to one born from one who was bonded to the shinju. Ex Hagoromo's mother Kaguya has the ocular powers of the shinju and its physical Mokuton as stated by Madara is derived from the shinju's sentient braches. Having both powers passed down to him he unlocked a water down eye. In turn the shinju's power was split between Hagoromo's sons the remaing power went into Indra's eyes filling them turning them into mirror eyes instead of emepty eyes and Ashura got the power stored into his body. My belief is that the hyuuga never received additional power in their eyes so it remained empty. To put it another term.
. Kaguya (dormant gentic ability is Byakugan)
..Kaguya + Shinju (grants the mokuton which represents the physical power and the shinju's ocular power which represents sprit) this grants the "third eye" dubbed by fans as the Sharrinnegan.
. Hagoromo- Son of Kaguya born with rinne as a result of being born WITH chakra but no having the same bond with the shinju that his mother did therefore his eye lacks sufficient strength and only has the rings.
.Indra and Ashura the power of the shiju degrades even further. Indra receives the spirit and only has the coloration and tome in his eyes to prove the presense of chakra. Ashura gains power in the body but lacks the ability to interact with the power in nature.
Hyuga as time went on and the sage gifted humanity with the teaching nesccary for them to genrate chakra from their own body's the hyuga lost the power or split off from the uchiha because the hyuga became a sect of uhiha who did not want to succumb to the curse of hatred the lack of chakra from the brain that is required to activate the sharingan allowed the hyugas' eyes to be CLEAR (metaphorically and literally).
Uchiha as time progressed they kept the power and the more spritual turmiol the go through the stronger they become ultimately once a sufficient amount of spiritual power and physical (ems+ senju dna) is acheived the rinne will awaken.
I dont think i need to go into deatil about the senju.
Third eye basically is a rinnegan which is a sharingan hopped up on steroids after steroids to achieve the next level.Its why Sasuke has an incomplete third eye in his left socket. The Sage gave him enough power to where he doesnt need the senju Dna to acheive the rinne however he is stuck between a basic rinne and the complete Shinju eye. Senju Dna at this point would either complete him or give him a power beyond Kaguya
. Kaguya (dormant gentic ability is Byakugan)
..Kaguya + Shinju (grants the mokuton which represents the physical power and the shinju's ocular power which represents sprit) this grants the "third eye" dubbed by fans as the Sharrinnegan.
. Hagoromo- Son of Kaguya born with rinne as a result of being born WITH chakra but no having the same bond with the shinju that his mother did therefore his eye lacks sufficient strength and only has the rings.
.Indra and Ashura the power of the shiju degrades even further. Indra receives the spirit and only has the coloration and tome in his eyes to prove the presense of chakra. Ashura gains power in the body but lacks the ability to interact with the power in nature.
Hyuga as time went on and the sage gifted humanity with the teaching nesccary for them to genrate chakra from their own body's the hyuga lost the power or split off from the uchiha because the hyuga became a sect of uhiha who did not want to succumb to the curse of hatred the lack of chakra from the brain that is required to activate the sharingan allowed the hyugas' eyes to be CLEAR (metaphorically and literally).
Uchiha as time progressed they kept the power and the more spritual turmiol the go through the stronger they become ultimately once a sufficient amount of spiritual power and physical (ems+ senju dna) is acheived the rinne will awaken.
I dont think i need to go into deatil about the senju.
Third eye basically is a rinnegan which is a sharingan hopped up on steroids after steroids to achieve the next level.Its why Sasuke has an incomplete third eye in his left socket. The Sage gave him enough power to where he doesnt need the senju Dna to acheive the rinne however he is stuck between a basic rinne and the complete Shinju eye. Senju Dna at this point would either complete him or give him a power beyond Kaguya