In this sketch, congruent quadrilaterals are joined edge to edge. You can vary the shape of the quadrilaterals by dragging the vertices at the yellow quadrilateral.
This sketch reveals a DR1 bug in the white space that occasionally appears between adjacent quadrilaterals. Polygon interiors in DR1 degrade JavaSketchpad's numeric accuracy; a coil of successive polygons shows the compound effects of such error.
If you drag the coil into oblivion, you can reset the sketch to its original shape by pressing the up-arrow key.
Go back to the JavaSketchpad demo gallery.