You can draw lines on the tablet by clicking on it. Each pair of clicks will createVrmlFromString.
You can rotate the tablet using the sphere sensor (the blue ball)
You can move the tablet using a plane sensor (the reddish cylinder)
You change to creating triangles by clicking on the cone.
You can undo the last creation by clicking on the red box.
You can change the current drawing color by clicking on the purple tetra. The tetra will show the new color.