Illusion de panoramique

The phenomenon by which horizontal rain, when superimposed upon distant landscapes (e.g. mountain ranges) creates a kaleidoscope effect where the panorama appears to move away from the viewer. Also known colloquially through the acronym as 'I.D.P.'

"Man, this horizontal rain is awful, but check out that I.D.P illusion de panoramique- those vistas are spacey!"