func TileFind(start *TileWrapper, goal Status, tilestate *TileState) env.Direction {
var pfstate t_pf_state
var node *t_pathnode
pfstate.init(env.MAX_SIZE * env.MAX_SIZE)
pfstate.setTilestate(tilestate)
pfstate.setStart(start, false)
node = pfstate.startNode
for len(pfstate.open) != 0 {
// Find the node with the lowest value for f()
// from the open list. As no heuristics are used,
// f() effectively returns the value of g.
node = pfstate.open[0]
for i := 1; i < len(pfstate.open); i++ {
if pfstate.open[i].f() < node.f() {
node = pfstate.open[i]
}
}
pfstate.addToClosed(node)
for i := 0; i < 4; i++ {
var dir env.Direction = env.Direction(i)
var status Status = tilestate.GetTileStatus(node.tile.tile, dir)
if status == goal {
// We cannot use the undiscovered tile in pathfinding
// because it hasn't been discovered yet. The link
// between the TileWrapper and the env.ITile is nil.
// However, if we started at a neighbouring tile, we
// already know the direction.
if start == node.tile {
return dir
}
// Return A* to the closest neighbouring tile (node).
return PathFind(start, node.tile, tilestate)
} else if status == TILE_DISCOVERED {
var wrapper *TileWrapper
var neighbour *t_pathnode
wrapper = tilestate.GetTile(node.tile, dir)
neighbour = pfstate.getPathnode(wrapper)
if pfstate.isOpen(neighbour) {
neighbour.parent = node
neighbour.g = node.g
} else if !pfstate.isClosed(neighbour) {
pfstate.addToOpen(neighbour)
neighbour.parent = node
neighbour.g = node.g
}
}
}
}
return env.NONE
}
func (a *Agent) performAction(action int, perf *util.SimPerf) {
switch action {
case NOOP:
case SUCK:
perf.AgentCleaned(a.currentTile.GetITile())
a.vacuumCurrent()
case int(env.UP):
fallthrough
case int(env.RIGHT):
fallthrough
case int(env.DOWN):
fallthrough
case int(env.LEFT):
var moved bool
moved = a.moveInDirection(env.Direction(action))
// If the agent successfully moved in the direction,
// notify the SimPerf of the dirt-status of the tile.
if moved {
tile := a.currentTile.GetITile()
perf.AgentEnteredTile(tile.GetState() == env.DIRTY)
perf.AgentMoved()
}
}
}
/* Returns the direction the agent should take in order to
* successfully arrive at the end-tile.
*/
func PathFind(start, end *TileWrapper, tilestate *TileState) env.Direction {
var pfstate t_pf_state
var node *t_pathnode
var success bool
pfstate.init(env.MAX_SIZE * env.MAX_SIZE)
pfstate.setTilestate(tilestate)
pfstate.setStart(start, true)
node = pfstate.startNode
for len(pfstate.open) != 0 {
// Find the node with the lowest value for f()
// from the open list
node = pfstate.open[0]
for i := 1; i < len(pfstate.open); i++ {
if pfstate.open[i].f() < node.f() {
node = pfstate.open[i]
}
}
// Stop searching when we've added the destination
// to the closed list
pfstate.addToClosed(node)
if node.tile == end {
success = true
break
}
for i := 0; i < 4; i++ {
var dir env.Direction = env.Direction(i)
var status Status = tilestate.GetTileStatus(node.tile.tile, dir)
if status == TILE_DISCOVERED {
var wrapper *TileWrapper
var neighbour *t_pathnode
wrapper = tilestate.GetTile(node.tile, dir)
neighbour = pfstate.getPathnode(wrapper)
if pfstate.isOpen(neighbour) {
neighbour.parent = node
neighbour.g = node.g
} else if !pfstate.isClosed(neighbour) {
pfstate.addToOpen(neighbour)
neighbour.parent = node
neighbour.g = node.g
}
}
}
}
if success && node.parent != nil {
for node.parent.parent != nil {
node = node.parent
}
// Get the relative position
x0, y0 := node.tile.tile.GetIndices()
x1, y1 := node.parent.tile.tile.GetIndices()
x := x0 - x1
y := y0 - y1
return env.GetDirection(x, y)
}
return env.NONE
}