1
|
|
|
<?php |
2
|
|
|
|
3
|
|
|
/** |
4
|
|
|
* Box packing (3D bin packing, knapsack problem). |
5
|
|
|
* |
6
|
|
|
* @author Doug Wright |
7
|
|
|
*/ |
8
|
|
|
declare(strict_types=1); |
9
|
|
|
|
10
|
|
|
namespace DVDoug\BoxPacker; |
11
|
|
|
|
12
|
|
|
use ArrayIterator; |
13
|
|
|
use Countable; |
14
|
|
|
use IteratorAggregate; |
15
|
|
|
use Traversable; |
16
|
|
|
|
17
|
|
|
use function array_map; |
18
|
|
|
use function count; |
19
|
|
|
use function usort; |
20
|
|
|
|
21
|
|
|
/** |
22
|
|
|
* List of packed items, ordered by volume. |
23
|
|
|
*/ |
24
|
|
|
class PackedItemList implements Countable, IteratorAggregate |
25
|
|
|
{ |
26
|
|
|
/** |
27
|
|
|
* @var PackedItem[] |
28
|
|
|
*/ |
29
|
|
|
private array $list = []; |
30
|
|
|
|
31
|
|
|
private int $weight = 0; |
32
|
|
|
|
33
|
|
|
private int $volume = 0; |
34
|
|
|
|
35
|
|
|
private bool $isSorted = false; |
36
|
98 |
|
|
37
|
|
|
public function insert(PackedItem $item): void |
38
|
98 |
|
{ |
39
|
98 |
|
$this->list[] = $item; |
40
|
98 |
|
$this->weight += $item->item->getWeight(); |
41
|
|
|
$this->volume += $item->width * $item->length * $item->depth; |
42
|
|
|
} |
43
|
|
|
|
44
|
|
|
/** |
45
|
|
|
* @return Traversable<PackedItem> |
46
|
87 |
|
*/ |
47
|
|
|
public function getIterator(): Traversable |
48
|
87 |
|
{ |
49
|
87 |
|
if (!$this->isSorted) { |
50
|
87 |
|
usort($this->list, $this->compare(...)); |
51
|
|
|
$this->isSorted = true; |
52
|
|
|
} |
53
|
87 |
|
|
54
|
|
|
return new ArrayIterator($this->list); |
55
|
|
|
} |
56
|
|
|
|
57
|
|
|
/** |
58
|
|
|
* Number of items in list. |
59
|
101 |
|
*/ |
60
|
|
|
public function count(): int |
61
|
101 |
|
{ |
62
|
|
|
return count($this->list); |
63
|
|
|
} |
64
|
|
|
|
65
|
|
|
/** |
66
|
|
|
* Get copy of this list as a standard PHP array. |
67
|
|
|
* |
68
|
|
|
* @internal |
69
|
|
|
* |
70
|
|
|
* @return Item[] |
71
|
9 |
|
*/ |
72
|
|
|
public function asItemArray(): array |
73
|
9 |
|
{ |
74
|
|
|
return array_map(fn (PackedItem $packedItem) => $packedItem->item, $this->list); |
75
|
|
|
} |
76
|
|
|
|
77
|
|
|
/** |
78
|
|
|
* Get total volume of these items. |
79
|
32 |
|
*/ |
80
|
|
|
public function getVolume(): int |
81
|
32 |
|
{ |
82
|
|
|
return $this->volume; |
83
|
|
|
} |
84
|
|
|
|
85
|
|
|
/** |
86
|
|
|
* Get total weight of these items. |
87
|
101 |
|
*/ |
88
|
|
|
public function getWeight(): int |
89
|
101 |
|
{ |
90
|
|
|
return $this->weight; |
91
|
|
|
} |
92
|
74 |
|
|
93
|
|
|
private function compare(PackedItem $itemA, PackedItem $itemB): int |
|
|
|
|
94
|
74 |
|
{ |
95
|
74 |
|
$itemAVolume = $itemA->item->getWidth() * $itemA->item->getLength() * $itemA->item->getDepth(); |
96
|
|
|
$itemBVolume = $itemB->item->getWidth() * $itemB->item->getLength() * $itemB->item->getDepth(); |
97
|
74 |
|
|
98
|
|
|
return ($itemBVolume <=> $itemAVolume) ?: ($itemB->item->getWeight() <=> $itemA->item->getWeight()); |
99
|
|
|
} |
100
|
|
|
} |
101
|
|
|
|
This check looks for private methods that have been defined, but are not used inside the class.