public function compute(Node $a, Node $b) { $f = sqrt(2) - 1; $dx = abs($a->getX() - $b->getX()); $dy = abs($a->getY() - $b->getY()); return $dx < $dy ? $f * $dx + $dy : $f * $dy + $dx; }
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 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 compute(Node $a, Node $b) { $dx = abs($a->getX() - $b->getX()); $dy = abs($a->getY() - $b->getY()); return max($dx, $dy); }
public function compute(Node $a, Node $b) { $dx = abs($a->getX() - $b->getX()); $dy = abs($a->getY() - $b->getY()); return sqrt($dx * $dx + $dy * $dy); }