Great software for Tilings, Patterns, Symmetry
A list of interactive, visual, easy-to-use software or tilings and patterns.
2018-06-22 girih app is written by Stefan Hintz. It's commercial software.
A tutorial on everything about hexagonal grids. Coordinate system, finding path, etc.
Kali (wallpaper symmetry)
http://www.geometrygames.org/Kali/index.html Windows Mac OS Classic
Kali by Jeff Weeks. It is a interactive program for drawing figures of plane symmetry.
See also: [Computer Graphics and Geometric Ornamental Design By Craig S Kaplan. At http://www.cgl.uwaterloo.ca/~csk/phd/]
If you have a question, put $5 at patreon and message me.