This graphics system is like classic Logo, but implemented in a way that is compatible with the vector-oriented data of J. The current system is in 3D.
This openGL version of tgsj, tgsjo, (turtle graphics system for j) employs the "modern" openGL which is used beginning in J807.
The files for this system can be found at A "modern" openGL turtle graphics/turtle geometry system using the J programming language. The files can be downloaded and loaded into jQT with the following commands.
install'github:zerowords/tgsjo' load 'zerowords/tgsjo' createTurtle 0 0 0 load '~addons/tgsjo/readme.ijs'
The Gosper flowsnake graphic above is drawn with this system. The code below was translated from the Logo at Wikipedia.
What follows is material that is dated. I am now developing the material above.