The linear perspective was first described only in its mathematical form around 1400. But it was invented much earlier. Wall paintings and mosaics in Rome and Pompeii of the first century BC already showed perspectives. The first paintings based on the principles of the perspective idea were thus created long before 1420.
If you analyze these paintings you see different perspectives (multi-point). Strictly scientific one can say that they violate the rigid rules of one-point perspective. However, they show the idea and the pragmatic understanding that lines that run parallel to the direction of the viewer’s gaze eventually converge in the plane of the picture at some point. This concept would most likely not have come about by chance or by eyeballing.
The mathematical and scientific description of this idea around 1400 is great but not the inventing, genius event.
These pictures are from the Villa Fanninus. Villa Fanninus is the name of a villa excavated at the foot of Vesuvius in the village of Boscoreale. It was built in the years 50-40 B.C. and was conserved by the Vesuvius eruption in 79 A.D.