Note the exaggerated perspective – Fra Anglico wanted us to see the real world beyond the scene and this was the era of the discovery of one point perspective
Here is the link to all the transcriptions of the videos. There are six videos in all including Fra Angelico, Botticelli, Mantegna, et al.
There is a sense of mystery in this painting. The lines of perspective lead from the angel’s eye. There soft curtains vs the hard columns. Angel Gabriel is announcing the birth of Jesus to Mary.
Does this genre of painting – this style whereby architecture is included with great detail and versimilitude – show where art is going in this period – the real world beyond the mystery story is creeping in and taking over.