This paper investigates the relation between anamorphosis and gnomonics in the baroque period. This comparison gives the possibility to analyse the possible use of light to calculate and create anamorphic projections. The relation between rays of vision and rays of light is also connected to the construction of sundials highlighting a similar physical behaviour of these two instruments in projection praxis. The final hypothesis considers the projection in geometry as a concept influenced by the use and study of light propagation
