Tile Types:
0 - Grass
1 - Path
2 - Water (obstacle)
3 - Tree/Wall (obstacle)
4 - House (portal)
Portal Format:
{
"x": x-position,
"y": y-position,
"width": width,
"height": height,
"targetRoom": "room-name",
"targetX": x-position-in-target,
"targetY": y-position-in-target,
"tile": optional-tile-index
}