emptygrid.json

{
	"width": 650,
	"height": 450,
	
	"start": [50, 35],
	"goals": [],
	"obstacles": [[[650, 30], [650, 0], [0, 0], [0, 30]],
          [[30, 450], [30, 0], [0, 0], [0, 450]],
          [[650, 450], [650, 420], [0, 420], [0, 450]],
          [[650, 450], [650, 0], [620, 0], [620, 450]]]
}