Spectre Tile with protrusions and indentations

Spectre Tile

This is a spectre tile made with OpenSCAD. There is only one model, so you can copy-paste and print as many as you need. While ordinary tiles collapse as soon as you arrange them, these tiles have hemispherical protrusions and concavities to realize the constraints of spectre tiles, so that you can keep them connected when you connect several of them as shown in the picture.