Fix inherited 3MF triangle property group resolution

tests/Unit/ThreeMfGeometryExtractorTest.php

@@ -2,7 +2,11 @@
 
 namespace Tests\Unit;
 
+use App\Services\ManufacturingFileValidator;
+use App\Services\ProductImageRenderer;
 use App\Services\ThreeMfGeometryExtractor;
+use Illuminate\Http\UploadedFile;
+use PHPUnit\Framework\Attributes\DataProvider;
 use RuntimeException;
 use Tests\TestCase;
 use ZipArchive;
@@ -131,6 +135,91 @@ class ThreeMfGeometryExtractorTest extends TestCase
         unlink($path);
     }
 
+    private function validatedTetrahedron(string $triangleProperties): string
+    {
+        $faces = '';
+        foreach ([[0, 2, 1], [0, 1, 3], [0, 3, 2], [1, 2, 3]] as [$v1, $v2, $v3]) {
+            $faces .= '<triangle v1="'.$v1.'" v2="'.$v2.'" v3="'.$v3.'" '.$triangleProperties.'/>';
+        }
+        $resources = '<m:colorgroup xmlns:m="http://schemas.microsoft.com/3dmanufacturing/material/2015/02" id="2">'
+            .'<m:color color="#FF0000"/><m:color color="#0000FF"/><m:color color="#00FF0080"/></m:colorgroup>'
+            .'<object id="1" type="model" pid="2" pindex="0"><mesh><vertices>'
+            .'<vertex x="0" y="0" z="0"/><vertex x="10" y="0" z="0"/>'
+            .'<vertex x="0" y="10" z="0"/><vertex x="0" y="0" z="10"/>'
+            .'</vertices><triangles>'.$faces.'</triangles></mesh></object>';
+        $path = $this->validArchive($this->model($resources, '<item objectid="1"/>'));
+        try {
+            $validated = (new ManufacturingFileValidator)->validate(new UploadedFile($path, 'tetrahedron.3mf', test: true));
+            $this->assertSame('3mf', $validated['extension']);
+        } catch (\Throwable $exception) {
+            unlink($path);
+            throw $exception;
+        }
+
+        return $path;
+    }
+
+    /** @return array<string, array{string}> */
+    public static function flatInheritedProperties(): array
+    {
+        return [
+            'p2 and p3 default to p1' => ['p1="1"'],
+            'all vertex properties specified' => ['p1="1" p2="1" p3="1"'],
+        ];
+    }
+
+    #[DataProvider('flatInheritedProperties')]
+    public function test_inherited_triangle_property_group_applies_flat_override_through_png_rendering(string $properties): void
+    {
+        $path = $this->validatedTetrahedron($properties);
+        try {
+            $scene = $this->extractor->extract($path);
+            $this->assertSame(4, $scene['triangle_count']);
+            foreach ($scene['triangles'] as $triangle) {
+                $this->assertSame([0, 0, 255, 255], $triangle['color']);
+            }
+            $rendered = (new ProductImageRenderer)->render($scene['triangles']);
+            $this->assertSame('image/png', $rendered['mime']);
+            $image = imagecreatefromstring($rendered['bytes']);
+            $this->assertNotFalse($image);
+            try {
+                $pixel = imagecolorsforindex($image, imagecolorat($image, 256, 256));
+                $this->assertSame(0, $pixel['red']);
+                $this->assertSame(0, $pixel['green']);
+                $this->assertGreaterThan(0, $pixel['blue']);
+                $this->assertSame(0, $pixel['alpha']);
+            } finally {
+                imagedestroy($image);
+            }
+        } finally {
+            unlink($path);
+        }
+    }
+
+    public function test_inherited_triangle_property_group_rejects_interpolated_override(): void
+    {
+        $path = $this->validatedTetrahedron('p1="0" p2="1" p3="0"');
+        try {
+            $this->expectException(RuntimeException::class);
+            $this->expectExceptionMessageMatches('/interpolat/i');
+            (new ProductImageRenderer)->render($this->extractor->extract($path)['triangles']);
+        } finally {
+            unlink($path);
+        }
+    }
+
+    public function test_inherited_triangle_property_group_rejects_transparent_override(): void
+    {
+        $path = $this->validatedTetrahedron('p1="2"');
+        try {
+            $this->expectException(RuntimeException::class);
+            $this->expectExceptionMessageMatches('/transparen/i');
+            (new ProductImageRenderer)->render($this->extractor->extract($path)['triangles']);
+        } finally {
+            unlink($path);
+        }
+    }
+
     public function test_resolves_object_level_color_from_a_colorgroup(): void
     {
         $resources = '<colorgroup id="5"><color color="#00CC33"/></colorgroup>'