A user-friendly terminal image viewer that uses graphic capabilities of terminals (Sixel, Kitty or iterm2), or 24-Bit color capabilities and unicode character blocks if these are not available. But ...
"I see in 3D" (iCn3D) Structure Viewer is not only a web-based 3D viewer, but also a structure analysis tool interactively or in the batch mode using NodeJS scripts based on the npm package icn3d.