An animated demonstration of the Ebbinghaus (Titchener circles) illusion: a central disk appears larger or smaller depending on the size of the surrounding circles, even when both central disks are physically identical.
This demo animates the surrounding circles so they continuously grow and shrink, making the perceptual size distortion easy to observe in real time.
sudo apt install libsdl3-dev on Ubuntu/Debian)# Fullscreen
go run main.go
# Windowed (development / testing)
go run main.go -d
| Flag | Default | Description |
|---|---|---|
-d |
off | Development mode: windowed 1024×768 |
Press Escape or Q to quit.
This is a demonstration, not a data-collecting experiment. No output file is written.