A nice pattern appeared on the wall when the sun was shining through a window with a structured glass panel (photo 1). A photo from the panel itself existed already and is added too (photo 2).
1
Sunny pattern projected on the wall, with light switch.
2
Sample of the glass panel (with environment seen through, rotated).
This last photo was actually a blind shot after loading a film but it was worked into an abstract composition as an exercise.
Camera photo 1: Nikon 1 V2, 18.5mm f/1.8 (50 mm equiv).
Camera photo 2: Olympus PEN-EE (half-frame), 28mm f/3.8 (42mm equiv), Kodak T-MAX 100.
Sunny pattern projected on the wall, with light switch.