Symmetry group P4g, a square mirror box with a four way rotation in the middle. Very constraining to build a flowing figure within such a rigid set of rules.  In the image below, starting in the middle of the square, the “x” indicates the four way rotation. Each line has its own colour here to give you an idea of the different operations. Take the red line and rotate it 3 more times to mauve, aqua and lime green. Then mirror each of those 4 lines across their mirrors. Then repeat and repeat.

One line, one fill tessellation by Francine Champagne, ©2016 — Symétruc simple

Here is the actual drawing without the operations highlighted. Over a barely visible white background, one simple black line and one red fill within it. That’s it! A little bit easier to understand than most of my tessellations.

One line, one fill tessellation by Francine Champagne, ©2016 — Symétruc simple

And the zoomed-out version of the same tessellation.

One line, one fill tessellation by Francine Champagne, ©2016 — Symétruc simple