Merge pull request #258 from sprain/round-block-size-modes

Add mode options for roundBlockSize

Author: endroid

README.md

@@ -45,6 +45,7 @@ use Endroid\QrCode\Response\QrCodeResponse;
 // Create a basic QR code
 $qrCode = new QrCode('Life is too short to be generating QR codes');
 $qrCode->setSize(300);
+$qrCode->setMargin(10); 
 
 // Set advanced options
 $qrCode->setWriterByName('png');
@@ -57,10 +58,11 @@ $qrCode->setLogoPath(__DIR__.'/../assets/images/symfony.png');
 $qrCode->setLogoSize(150, 200);
 $qrCode->setValidateResult(false);
 
-// Apply a margin and round block sizes to improve readability
-// Please note that rounding block sizes can result in additional margin
-$qrCode->setRoundBlockSize(true);
-$qrCode->setMargin(10); 
+// Round block sizes to improve readability and make the blocks sharper in pixel based outputs (like png).
+// There are three approaches:
+$qrCode->setRoundBlockSize(true, QrCode::ROUND_BLOCK_SIZE_MODE_MARGIN); // The size of the qr code is shrinked, if necessary, but the size of the final image remains unchanged due to additional margin being added (default)
+$qrCode->setRoundBlockSize(true, QrCode::ROUND_BLOCK_SIZE_MODE_ENLARGE); // The size of the qr code and the final image is enlarged, if necessary
+$qrCode->setRoundBlockSize(true, QrCode::ROUND_BLOCK_SIZE_MODE_SHRINK); // The size of the qr code and the final image is shrinked, if necessary
 
 // Set additional writer options (SvgWriter example)
 $qrCode->setWriterOptions(['exclude_xml_declaration' => true]);

src/QrCode.php

@@ -20,6 +20,10 @@ class QrCode implements QrCodeInterface
 {
     const LABEL_FONT_PATH_DEFAULT = __DIR__.'/../assets/fonts/noto_sans.otf';
 
+    const ROUND_BLOCK_SIZE_MODE_MARGIN = 'margin';
+    const ROUND_BLOCK_SIZE_MODE_SHRINK = 'shrink';
+    const ROUND_BLOCK_SIZE_MODE_ENLARGE = 'enlarge';
+
     private $text;
 
     /** @var int */
@@ -50,6 +54,9 @@ class QrCode implements QrCodeInterface
     /** @var bool */
     private $roundBlockSize = true;
 
+    /** @var string */
+    private $roundBlockSizeMode = self::ROUND_BLOCK_SIZE_MODE_MARGIN;
+
     private $errorCorrectionLevel;
 
     /** @var string */
@@ -178,9 +185,10 @@ public function getEncoding(): string
         return $this->encoding;
     }
 
-    public function setRoundBlockSize(bool $roundBlockSize): void
+    public function setRoundBlockSize(bool $roundBlockSize, string $mode = self::ROUND_BLOCK_SIZE_MODE_MARGIN): void
     {
         $this->roundBlockSize = $roundBlockSize;
+        $this->roundBlockSizeMode = $mode;
     }
 
     public function getRoundBlockSize(): bool
@@ -422,7 +430,19 @@ public function getData(): array
         $data['block_count'] = count($matrix[0]);
         $data['block_size'] = $this->size / $data['block_count'];
         if ($this->roundBlockSize) {
-            $data['block_size'] = intval(floor($data['block_size']));
+            switch($this->roundBlockSizeMode) {
+                case self::ROUND_BLOCK_SIZE_MODE_ENLARGE:
+                    $data['block_size'] = intval(ceil($data['block_size']));
+                    $this->size = $data['block_size'] * $data['block_count'];
+                    break;
+                case self::ROUND_BLOCK_SIZE_MODE_SHRINK:
+                    $data['block_size'] = intval(floor($data['block_size']));
+                    $this->size = $data['block_size'] * $data['block_count'];
+                    break;
+                case self::ROUND_BLOCK_SIZE_MODE_MARGIN:
+                default:
+                    $data['block_size'] = intval(floor($data['block_size']));
+            }
         }
         $data['inner_width'] = $data['block_size'] * $data['block_count'];
         $data['inner_height'] = $data['block_size'] * $data['block_count'];

tests/QrCodeTest.php

@@ -147,6 +147,72 @@ public function testSetSize(): void
         $this->assertTrue(imagesy($image) === $size + 2 * $margin);
     }
 
+    /**
+     * @testdox Size and margin are handled correctly with rounded blocks
+     * @dataProvider roundedSizeProvider
+     */
+    public function testSetSizeRounded($size, $margin, $round, $mode, $expectedSize): void
+    {
+        $qrCode = new QrCode('QR Code contents with some length to have some data');
+        $qrCode->setRoundBlockSize($round, $mode);
+        $qrCode->setSize($size);
+        $qrCode->setMargin($margin);
+
+        $pngData = $qrCode->writeString();
+        $image = imagecreatefromstring($pngData);
+
+        $this->assertTrue(imagesx($image) === $expectedSize);
+        $this->assertTrue(imagesy($image) === $expectedSize);
+    }
+
+    public function roundedSizeProvider()
+    {
+        return [
+            [
+                'size' => 400,
+                'margin' => 0,
+                'round' => true,
+                'mode' => QrCode::ROUND_BLOCK_SIZE_MODE_ENLARGE,
+                'expectedSize' => 406
+            ],
+            [
+                'size' => 400,
+                'margin' => 5,
+                'round' => true,
+                'mode' => QrCode::ROUND_BLOCK_SIZE_MODE_ENLARGE,
+                'expectedSize' => 416
+            ],
+            [
+                'size' => 400,
+                'margin' => 0,
+                'round' => true,
+                'mode' => QrCode::ROUND_BLOCK_SIZE_MODE_MARGIN,
+                'expectedSize' => 400
+            ],
+            [
+                'size' => 400,
+                'margin' => 5,
+                'round' => true,
+                'mode' => QrCode::ROUND_BLOCK_SIZE_MODE_MARGIN,
+                'expectedSize' => 410
+            ],
+            [
+                'size' => 400,
+                'margin' => 0,
+                'round' => true,
+                'mode' => QrCode::ROUND_BLOCK_SIZE_MODE_SHRINK,
+                'expectedSize' => 377
+            ],
+            [
+                'size' => 400,
+                'margin' => 5,
+                'round' => true,
+                'mode' => QrCode::ROUND_BLOCK_SIZE_MODE_SHRINK,
+                'expectedSize' => 387
+            ],
+        ];
+    }
+
     /**
      * @testdox Label can be added and QR code is still readable
      */