This image is a drawing of a basilica that da Vinci created. After he read The Vitrivian Man when visiting Pavia in 1490, he was inspired to create buildings that were like that of a human and being connected to its surroundings. The use of geometric shapes like circles and squares have an element of humanism to them because they were used in the drawing of The Vituvian Man, where it depicts the human being inscribed in a circle and a square. This implies that the church, like the human, fits in a certain ratio that is universal in nature.
Source: Craven, Jackie. “Hidden Codes: How Geometry Shapes Architecture.” ThoughtCo, ThoughtCo, 3 July 2019, www.thoughtco.com/geometry-and-architecture-178081
Image: https://www.leonardodavinci.net/study-of-a-central-church.jsp