Completed
Push — master ( c370bc...fc6c9b )
by Christopher
01:58
created

ConnectedDifferences::cloneWith()   A

Complexity

Conditions 1
Paths 1

Size

Total Lines 7
Code Lines 4

Duplication

Lines 0
Ratio 0 %

Code Coverage

Tests 0
CRAP Score 2

Importance

Changes 1
Bugs 0 Features 1
Metric Value
c 1
b 0
f 1
dl 0
loc 7
ccs 0
cts 6
cp 0
rs 9.4285
cc 1
eloc 4
nc 1
nop 2
crap 2
1
<?php
2
3
namespace Undemanding\Difference;
4
5
class ConnectedDifferences
6
{
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    /**
8
     * @var array
9
     */
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    private $bitmap;
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    /**
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     * @var int
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     */
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    private $width;
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    /**
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     * @var int
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     */
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    private $height;
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    /**
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     * @var array
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     */
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    private $boundaries = [];
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    /**
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     * @param Difference $difference
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     */
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    public function __construct(Difference $difference)
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    {
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        $this->bitmap = $difference->getBitmap();
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        $this->width = $difference->getWidth();
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        $this->height = $difference->getHeight();
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        $this->boundaries = $this->findBoundaries();
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    }
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    /**
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     * Find separate boundaries.
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     *
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     * @return array
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     */
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    private function findBoundaries()
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    {
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        $pixels = [];
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        for ($y = 0; $y < $this->height; $y++) {
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            for ($x = 0; $x < $this->width; $x++) {
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                if ($this->bitmap[$y][$x] > 0) {
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                    $pixels["{$x}:{$y}"] = [
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                        "group" => null,
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                        "x" => $x,
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                        "y" => $y,
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                    ];
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                }
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            }
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        }
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        $group = 1;
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        $boundaries = [];
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        foreach ($pixels as $i => $pixel) {
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            $adjacent = $this->adjacent($pixel);
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            if (!$pixel["group"]) {
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                foreach ($adjacent as $key) {
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                    if (isset($pixels[$key]) and $pixels[$key]["group"]) {
0 ignored issues
show
Comprehensibility Best Practice introduced by
Using logical operators such as and instead of && is generally not recommended.

PHP has two types of connecting operators (logical operators, and boolean operators):

  Logical Operators Boolean Operator
AND - meaning and &&
OR - meaning or ||

The difference between these is the order in which they are executed. In most cases, you would want to use a boolean operator like &&, or ||.

Let’s take a look at a few examples:

// Logical operators have lower precedence:
$f = false or true;

// is executed like this:
($f = false) or true;


// Boolean operators have higher precedence:
$f = false || true;

// is executed like this:
$f = (false || true);

Logical Operators are used for Control-Flow

One case where you explicitly want to use logical operators is for control-flow such as this:

$x === 5
    or die('$x must be 5.');

// Instead of
if ($x !== 5) {
    die('$x must be 5.');
}

Since die introduces problems of its own, f.e. it makes our code hardly testable, and prevents any kind of more sophisticated error handling; you probably do not want to use this in real-world code. Unfortunately, logical operators cannot be combined with throw at this point:

// The following is currently a parse error.
$x === 5
    or throw new RuntimeException('$x must be 5.');

These limitations lead to logical operators rarely being of use in current PHP code.

Loading history...
69
                        $pixel["group"] = $pixels[$key]["group"];
70
                    }
71
                }
72
            }
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            if (!$pixel["group"]) {
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                $pixel["group"] = $group++;
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            }
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            foreach ($adjacent as $key) {
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                if (isset($pixels[$key])) {
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                    $pixels[$key]["group"] = $pixel["group"];
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                }
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            }
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        }
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        $groups = array_values(array_unique(array_map(function($pixel) {
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            return $pixel["group"];
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        }, $pixels)));
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        foreach ($groups as $group) {
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            $filtered = array_filter($pixels, function($pixel) use ($group) {
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                return $pixel["group"] === $group;
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            });
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            $ax = $this->width;
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            $bx = 0;
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            $ay = $this->height;
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            $by = 0;
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            foreach ($filtered as $pixel) {
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                $x = $pixel["x"];
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                $y = $pixel["y"];
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                if ($x > $bx) {
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                    $bx = $x;
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                }
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                if ($x < $ax) {
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                    $ax = $x;
109
                }
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                if ($y > $by) {
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                    $by = $y;
113
                }
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                if ($y < $ay) {
116
                    $ay = $y;
117
                }
118
            }
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            array_push($boundaries, [
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                "top" => $ay,
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                "right" => $bx,
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                "bottom" => $by,
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                "left" => $ax,
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            ]);
126
        }
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        return $boundaries;
129
    }
130
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    /**
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     * @return ConnectedDifferences
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     */
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    public function withJoinedBoundaries()
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    {
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        $keep = [];
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        foreach ($this->boundaries as $boundary) {
139
            foreach ($keep as $i => $kept) {
140
                if ($this->intersect($boundary, $kept)) {
141 View Code Duplication
                    if ($boundary["top"] < $kept["top"]) {
0 ignored issues
show
Duplication introduced by
This code seems to be duplicated across your project.

Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation.

You can also find more detailed suggestions in the “Code” section of your repository.

Loading history...
142
                        $keep[$i]["top"] = $boundary["top"];
143
                    }
144
145 View Code Duplication
                    if ($boundary["right"] > $kept["right"]) {
0 ignored issues
show
Duplication introduced by
This code seems to be duplicated across your project.

Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation.

You can also find more detailed suggestions in the “Code” section of your repository.

Loading history...
146
                        $keep[$i]["right"] = $boundary["right"];
147
                    }
148
149 View Code Duplication
                    if ($boundary["bottom"] > $kept["bottom"]) {
0 ignored issues
show
Duplication introduced by
This code seems to be duplicated across your project.

Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation.

You can also find more detailed suggestions in the “Code” section of your repository.

Loading history...
150
                        $keep[$i]["bottom"] = $boundary["bottom"];
151
                    }
152
153 View Code Duplication
                    if ($boundary["left"] < $kept["left"]) {
0 ignored issues
show
Duplication introduced by
This code seems to be duplicated across your project.

Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation.

You can also find more detailed suggestions in the “Code” section of your repository.

Loading history...
154
                        $keep[$i]["left"] = $boundary["left"];
155
                    }
156
157
                    continue 2;
158
                }
159
            }
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161
            array_push($keep, $boundary);
162
        }
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        return $this->cloneWith("boundaries", $keep);
165
    }
166
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    /**
168
     * @param string $property
169
     * @param mixed $value
170
     *
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     * @return ConnectedDifferences
172
     */
173
    private function cloneWith($property, $value)
174
    {
175
        $clone = clone $this;
176
        $clone->$property = $value;
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        return $clone;
179
    }
180
181
    /**
182
     * Labels for adjacent pixels.
183
     *
184
     * @param array $pixel
185
     *
186
     * @return array
187
     */
188
    private function adjacent($pixel)
189
    {
190
        $adjacent = [
191
            ($pixel["x"] - 1) . ":" . ($pixel["y"] - 1),
192
            ($pixel["x"] - 1) . ":" . $pixel["y"],
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            ($pixel["x"] - 1) . ":" . ($pixel["y"] + 1),
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            $pixel["x"] . ":" . ($pixel["y"] - 1),
195
            $pixel["x"] . ":" . ($pixel["y"] + 1),
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            ($pixel["x"] + 1) . ":" . ($pixel["y"] - 1),
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            ($pixel["x"] + 1) . ":" . $pixel["y"],
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            ($pixel["x"] + 1) . ":" . ($pixel["y"] + 1),
199
        ];
200
        return $adjacent;
201
    }
202
203
    /**
204
     * Tell if two boundaries overlap.
205
     *
206
     * @param array $p
207
     * @param array $q
208
     *
209
     * @return bool
210
     */
211
    private function intersect(array $p, array $q)
212
    {
213
        return max($p["left"], $q["left"]) <= min($p["right"], $q["right"]) and max($p["top"], $q["top"]) <= min($p["bottom"], $q["bottom"]);
0 ignored issues
show
Comprehensibility Best Practice introduced by
Using logical operators such as and instead of && is generally not recommended.

PHP has two types of connecting operators (logical operators, and boolean operators):

  Logical Operators Boolean Operator
AND - meaning and &&
OR - meaning or ||

The difference between these is the order in which they are executed. In most cases, you would want to use a boolean operator like &&, or ||.

Let’s take a look at a few examples:

// Logical operators have lower precedence:
$f = false or true;

// is executed like this:
($f = false) or true;


// Boolean operators have higher precedence:
$f = false || true;

// is executed like this:
$f = (false || true);

Logical Operators are used for Control-Flow

One case where you explicitly want to use logical operators is for control-flow such as this:

$x === 5
    or die('$x must be 5.');

// Instead of
if ($x !== 5) {
    die('$x must be 5.');
}

Since die introduces problems of its own, f.e. it makes our code hardly testable, and prevents any kind of more sophisticated error handling; you probably do not want to use this in real-world code. Unfortunately, logical operators cannot be combined with throw at this point:

// The following is currently a parse error.
$x === 5
    or throw new RuntimeException('$x must be 5.');

These limitations lead to logical operators rarely being of use in current PHP code.

Loading history...
214
    }
215
216
    /**
217
     * @return array
218
     */
219
    public function boundaries()
220
    {
221
        return $this->boundaries;
222
    }
223
}
224