Extended Reality Ante Litteram in the Ephemeral Apparatuses of Andrea Pozzo

The ephemeral apparatuses that Andrea Pozzo proposed in his treatise Perspectiva pictorum et architectorum can be considered an example of Extended Reality ante litteram. This consideration gave rise to the idea of developing some Augmented Reality experiences to introduce, to the general public, the Circular Work, one of the illusory tabernacles proposed by Pozzo for the celebration of the Forty Hours. Through Augmented Reality, in fact, one can simulate the presence of the illusory apparatus inside the church of St. Ignatius in Rome, where Pozzo himself set it up for the celebration of Holy Thursday and Good Friday, but also make visible the geometric principles underlying the illusory artifice. During the European Researchers’ Night 2023, visitors to the church of St. Ignatius were able to use different applications, of varying technical complexity, directly in the church, experiencing the illusory artifice and learning the principles that make it possible. On this occasion it was possible to verify how the illusory suggestion conveyed through Augmented Reality experiences is effective even in the case of its simplest variants.