turtlefreeze is an interpreter for the esoteric language
Brainfuck
extended with turtle graphics commands inspired by the
Logo language.
Brainfuck Commands
| > | increment the data pointer (move right) |
| < | decrement the data pointer (move left) |
| + | increment the byte at the data pointer (255 → 0) |
| - | decrement the byte at the data pointer (0 → 255) |
| [ | if the byte at the data pointer is zero, jump forward to the command after the matching ] |
| ] | if the byte at the data pointer is nonzero, jump back to the command after the matching [ |
Turtle Commands
N = value of the current memory cell. The cell value remains unchanged.
| { | turn turtle left by 360°/N (if N=0 → golden angle ≈137.5°) |
| } | turn turtle right by 360°/N (if N=0 → golden angle) |
| ^ | move turtle forward by N pixels |
| _ | pen down (draw lines when moving) |
| ~ | pen up (move without drawing) |
Viewport Controls
| mouse wheel | zoom relative to cursor position |
| left click + drag | pan the view |
| double click | reset view (zoom=1, offset=0) |
Tips
- Click any cell on the memory tape to manually input a value (0–255).
- The group +/−/</> checkbox speeds up execution of identical command sequences.
- The RUN button preserves your current zoom and offset. To re-render lines sharply after zooming, simply click RUN again.