private function getOptimalFlowDirections($xx, $yy, $zz)
{
$flowCost = [0, 0, 0, 0];
$isOptimalFlowDirection = [0, 0, 0, 0];
for ($j = 0; $j < 4; ++$j) {
$flowCost[$j] = 1000;
$x = $xx;
$y = $yy;
$z = $zz;
if ($j === 0) {
--$x;
} elseif ($j === 1) {
++$x;
} elseif ($j === 2) {
--$z;
} elseif ($j === 3) {
++$z;
}
if (!$this->canFlowInto($x, $y, $z)) {
continue;
} elseif ($this->canFlowInto($x, $y, $z) and $this->level->getBlockDataAt($x, $y, $z) === 0) {
continue;
} elseif ($this->canFlowInto($x, $y - 1, $z)) {
$flowCost[$j] = 0;
} else {
$flowCost[$j] = $this->calculateFlowCost($x, $y, $z, 1, $j);
}
}
$minCost = $flowCost[0];
for ($i = 1; $i < 4; ++$i) {
if ($flowCost[$i] < $minCost) {
$minCost = $flowCost[$i];
}
}
for ($i = 0; $i < 4; ++$i) {
$isOptimalFlowDirection[$i] = $flowCost[$i] === $minCost;
}
return $isOptimalFlowDirection;
}
