This search for mystic geometry is totally misguided, as, in general, is the search for "codes". None of the huge body of evidence about the design of Renaissance paintings (Leonardo's included) provides the slightest encouragement for the imposing of detailed surface geometry (using thick lines on small reproductions) on paintings in this way. The most there may be is an adherence to certain canons of bodily proportion, but none of his drawings for specific works of art contain even this. Renaissance paintings contain allegories and symbolism, but there are no "codes". The nature of a code is that it's meaning is as unlike surface appearance as possible. Allegory and symbolism convey deeper meanings that are consistent with the immediate content of the image.
"Da Vinci" is not his name - that's an ugly Americanism. It's like calling me "from Woodstock". It was not a surname.