He composed an architectural treatise "Trattato di architettura, ingegneria e arte militare", the third of the Quattrocento, after Leone Battista Alberti's and Filarete's; he worked on it for decades and finished sometime after 1482; it circulated in manuscript. The projects were well in advance of completed projects at the time, but innovations, for example in staircase planning, running in flights and landings round an open center, or dividing at a landing to return symmetrically on each wall, became part of architectural vocabulary in the following century. The third book is preoccupied with the "ideal" city, constrained within star-shaped polygonal geometries reminiscent of the star fort, whose wedge-shaped bastions are said to have been his innovation.