public function computePath(Node $source, Node $target)
{
if (!$this->grid instanceof NodeGrid) {
throw new \RuntimeException('Invalid Grid');
}
$priorityQueue = new NodePriorityQueueMin();
$distanceMap = new NodeMap();
$previousMap = new NodeMap();
$priorityQueue->insert($source, 0);
$distanceMap->insert($source, 0);
while (!$priorityQueue->isEmpty()) {
$node = $priorityQueue->extract();
if ($node->getId() === $target->getId()) {
return new NodePath($previousMap->lookupFrom($node));
}
$neighbors = $this->grid->getWalkableNeighbors($node);
foreach ($neighbors as $neighbor) {
$alternativeDistance = $distanceMap->lookup($node) + $this->distance->compute($node, $neighbor);
if (!$distanceMap->exists($neighbor) || $alternativeDistance < $distanceMap->lookup($neighbor)) {
$priorityQueue->insert($neighbor, $alternativeDistance);
$distanceMap->insert($neighbor, $alternativeDistance);
$previousMap->insert($neighbor, $node);
}
}
}
return array();
// no path found
}
public function computeRoute()
{
if (!$this->graph instanceof NodeGraph) {
throw new \RuntimeException('Invalid Graph');
}
$vertexes = $this->graph->getVertexes();
if (count($vertexes) <= 2) {
return new NodePath($vertexes);
}
$vertexFrom = array_shift($vertexes);
$vertexTo = null;
$pathMap = new NodeMap();
$pathMap->insert($vertexFrom, $vertexTo);
while (!empty($vertexes)) {
$minimalVertexTo = null;
$minimalEdge = INF;
$edges = $this->graph->getEdgesFrom($vertexFrom);
foreach ($edges as $vertexToId => $edge) {
$vertexTo = $this->graph->getVertex($vertexToId);
if (!$pathMap->exists($vertexTo) && $edge < $minimalEdge) {
$minimalVertexTo = $vertexTo;
$minimalEdge = $edge;
}
}
$pathMap->insert($minimalVertexTo, $vertexFrom);
unset($vertexes[$minimalVertexTo->getId()]);
$vertexFrom = $minimalVertexTo;
}
return new NodePath($pathMap->lookupFrom($vertexFrom));
}
public function computePath(Node $source, Node $target)
{
if (!$this->grid instanceof NodeGrid) {
throw new \RuntimeException('Invalid Grid');
}
$fScorePriorityQueue = new NodePriorityQueueMin();
$gScoreMap = new NodeMap();
$openedMap = new NodeMap();
$closedMap = new NodeMap();
$previousMap = new NodeMap();
$fScorePriorityQueue->insert($source, 0);
$gScoreMap->insert($source, 0);
$openedMap->insert($source);
while (!$fScorePriorityQueue->isEmpty()) {
$node = $fScorePriorityQueue->extract();
$closedMap->insert($node);
if ($node->getId() === $target->getId()) {
return new NodePath($previousMap->lookupFrom($node));
}
$neighbors = $this->grid->getWalkableNeighbors($node);
foreach ($neighbors as $neighbor) {
if ($closedMap->exists($neighbor)) {
continue;
}
$gScore = $gScoreMap->lookup($node) + $this->distance->compute($node, $neighbor);
if (!$openedMap->exists($neighbor) || $gScore < $gScoreMap->lookup($neighbor)) {
$fScore = $gScore + $this->heuristic->compute($node, $target);
$fScorePriorityQueue->insert($neighbor, $fScore);
$gScoreMap->insert($neighbor, $gScore);
$openedMap->insert($neighbor);
$previousMap->insert($neighbor, $node);
}
}
}
// no path found
return array();
}
public function testMap()
{
$map = new NodeMap();
$node = new Node(1, 1);
$aNode = new Node(2, 1);
$bNode = new Node(2, 2);
$cNode = new Node(2, 3);
$dNode = new Node(3, 1);
$eNode = new Node(3, 2);
$fNode = new Node(3, 3);
$map->insert($node, 10);
$this->assertTrue($map->exists($node));
$this->assertSame($map->lookup($node), 10);
$this->assertSame($map->delete($node), 10);
$this->assertTrue($map->isEmpty());
$this->assertFalse($map->exists($node));
$map->insert($aNode, 'a');
$map->insert($bNode, 'c');
$map->insert($cNode, 'b');
$this->assertSame($map->lookup($aNode), 'a');
$this->assertSame($map->lookup($bNode), 'c');
$this->assertSame($map->lookup($cNode), 'b');
$map->insert($bNode, 'b');
$map->insert($cNode, 'c');
$this->assertSame($map->lookup($aNode), 'a');
$this->assertSame($map->lookup($bNode), 'b');
$this->assertSame($map->lookup($cNode), 'c');
$map->insert(new Node(2, 2), 'b_');
$map->insert(new Node(2, 3), 'c_');
$this->assertSame($map->delete($aNode), 'a');
$this->assertSame($map->delete($bNode), 'b_');
$this->assertSame($map->delete($cNode), 'c_');
$this->assertTrue($map->isEmpty());
$map->insert($fNode, $eNode);
$map->insert($eNode, $dNode);
$map->insert($dNode, $cNode);
$map->insert($cNode, $bNode);
$map->insert($bNode, $aNode);
$this->assertSamePath(array($aNode, $bNode, $cNode, $dNode, $eNode, $fNode), $map->lookupFrom($fNode));
$this->assertSamePath(array($aNode, $bNode, $cNode, $dNode), $map->lookupFrom($dNode));
$map->insert($bNode, $aNode);
$map->insert($cNode, $bNode);
$map->insert($dNode, $cNode);
$map->insert($eNode, $dNode);
$map->insert($fNode, $eNode);
$this->assertSamePath(array($aNode, $bNode, $cNode, $dNode, $eNode, $fNode), $map->lookupFrom($fNode));
$this->assertSamePath(array($aNode, $bNode, $cNode, $dNode), $map->lookupFrom($dNode));
$map->insert($eNode, $fNode);
$map->insert($fNode, $eNode);
$this->assertSamePath(array($eNode, $fNode), $map->lookupFrom($fNode));
$this->assertSamePath(array($fNode, $eNode), $map->lookupFrom($eNode));
$map->insert($eNode, $eNode);
$this->assertSamePath(array($eNode), $map->lookupFrom($eNode));
}
