In experimenting with virtual reality, augmented reality I’ve been very interested in the notion of depth. Depth perception — the use of our two human eyes. Why depth?
1. Color heat map, for depth
Red as closest to us, then blue a little further, then green furthest back:

2. Virtual reality depth mapping
Oculus Rift S+ gravity sketch app, and toggling the “depth” map:
Also, using Google Tilt Brush to create brief animated GIF (wiggling left and right) as a means to better see and understand the depth in a scene: