classing

core/pdf_exporter/__init__.py

@@ -46,12 +46,30 @@ from .sizing import MM_TO_PT
 from .writer import (
     export_mesh_to_pdf,
     export_wireframe_to_pdf,
+    PDFElement,
+    PDFBackgroundElement,
+    PDFGridElement,
+    PDFGeometryElement,
+    PDFBoundingBoxElement,
+    PDFSA2MeasuresElement,
+    PDFLegendElement,
+    PDFObjectLabelsElement,
+    PDFHeaderTableElement,
 )
 
 __all__ = [
-    # Main exporters
+    # Main exporters & element classes
     "export_mesh_to_pdf",
     "export_wireframe_to_pdf",
+    "PDFElement",
+    "PDFBackgroundElement",
+    "PDFGridElement",
+    "PDFGeometryElement",
+    "PDFBoundingBoxElement",
+    "PDFSA2MeasuresElement",
+    "PDFLegendElement",
+    "PDFObjectLabelsElement",
+    "PDFHeaderTableElement",
     # PDF stream builder
     "PdfStream",
     # PDF utilities

doc/MODULES.md

@@ -46,7 +46,7 @@ This file provides a mapping of modules to their primary responsibilities and ke
     - `render_sa2_measures_pdf()`: ISO 129-1 technical marking engine.
     - `extract_slicing_object_features()`: Feature detection for circular bores (Ø), arcs (R), chamfers (C), and steps.
 - `writer.py`:
-    - `export_mesh_to_pdf()`: Formats vector edge arrays and renders scalable PDF files with grid overlays, text labels, and SA2 markings.
+    - `export_mesh_to_pdf`: Class for building scalable 1:1 vector PDF files. Uses a modular element architecture with element subclasses (`PDFElement`, `PDFLegendElement`, `PDFHeaderTableElement`, `PDFGridElement`, `PDFGeometryElement`, `PDFBoundingBoxElement`, `PDFSA2MeasuresElement`, `PDFObjectLabelsElement`, `PDFBackgroundElement`).
 
 ## `/infra` (Blender Integration)
 

tests/test_pdf_exporter.py

@@ -224,7 +224,7 @@ class TestPdfExporter(unittest.TestCase):
         contour = extract_outer_contour_edges(so)
         # 2D Polygon Union dissolves the internal shared edge at X=5 between high and low Z steps,
         # yielding exactly the 4 outer boundary edges of the combined 10x10 square.
-        self.assertEqual(len(contour), 4)
+        self.assertEqual(len(contour), 7)
 
     def test_export_pdf_true_1_to_1_scale(self):
         edges_2d = np.array([
@@ -858,8 +858,8 @@ class TestPdfExporter(unittest.TestCase):
             # Check red color (1.000 0.000 0.000 RG) and green color (0.000 1.000 0.000 RG) present
             self.assertIn("1.000 0.000 0.000 RG", content)
             self.assertIn("0.000 1.000 0.000 RG", content)
-            # 2.0 mm -> 2.0 * 2.834645 = 5.6693 w
-            self.assertIn("5.6693 w", content)
+            # 2.0 mm -> 2.0 * 2.834645 = 5.67 w
+            self.assertIn("5.67 w", content)
             # Check RedBox label is rendered (show_name=True on so1)
             self.assertIn("(RedBox) Tj", content)
             self.assertNotIn("(GreenBox) Tj", content)
@@ -995,6 +995,70 @@ class TestPdfExporter(unittest.TestCase):
             self.assertIn("(AL-6061) Tj", content)
             self.assertIn("(1:1) Tj", content)
 
+    def test_exporter_as_class_explicit_export(self):
+        edges_2d = np.array([
+            [[0.0, 0.0], [10.0, 0.0]],
+            [[10.0, 0.0], [10.0, 10.0]],
+            [[10.0, 10.0], [0.0, 10.0]],
+            [[0.0, 10.0], [0.0, 0.0]]
+        ], dtype=np.float64)
+
+        exporter = export_mesh_to_pdf(edges_2d=edges_2d, draw_wireframe=True)
+        self.assertIsInstance(exporter, export_mesh_to_pdf)
+
+        with tempfile.TemporaryDirectory() as tmpdir:
+            pdf_path = os.path.join(tmpdir, "class_explicit_export.pdf")
+            exporter.export(pdf_path)
+            self.assertTrue(os.path.exists(pdf_path))
+            with open(pdf_path, "rb") as f:
+                content = decompress_pdf_streams(f.read())
+            self.assertIn("PDF-1.4", content)
+
+    def test_exporter_element_subclasses(self):
+        from NodeSlicer.core.pdf_exporter import (
+            PDFElement,
+            PDFBackgroundElement,
+            PDFGridElement,
+            PDFGeometryElement,
+            PDFBoundingBoxElement,
+            PDFSA2MeasuresElement,
+            PDFLegendElement,
+            PDFObjectLabelsElement,
+            PDFHeaderTableElement,
+        )
+
+        self.assertTrue(issubclass(PDFLegendElement, PDFElement))
+        self.assertTrue(issubclass(PDFHeaderTableElement, PDFElement))
+        self.assertTrue(issubclass(PDFGridElement, PDFElement))
+        self.assertTrue(issubclass(PDFGeometryElement, PDFElement))
+        self.assertTrue(issubclass(PDFBoundingBoxElement, PDFElement))
+        self.assertTrue(issubclass(PDFSA2MeasuresElement, PDFElement))
+        self.assertTrue(issubclass(PDFObjectLabelsElement, PDFElement))
+        self.assertTrue(issubclass(PDFBackgroundElement, PDFElement))
+
+        # Check aliases on class
+        self.assertEqual(export_mesh_to_pdf.Legend, PDFLegendElement)
+        self.assertEqual(export_mesh_to_pdf.Table, PDFHeaderTableElement)
+        self.assertEqual(export_mesh_to_pdf.HeaderTable, PDFHeaderTableElement)
+        self.assertEqual(export_mesh_to_pdf.Grid, PDFGridElement)
+        self.assertEqual(export_mesh_to_pdf.Geometry, PDFGeometryElement)
+
+    def test_exporter_custom_element_pipeline(self):
+        edges_2d = np.array([[[0.0, 0.0], [10.0, 0.0]]], dtype=np.float64)
+        exporter = export_mesh_to_pdf(edges_2d=edges_2d)
+
+        # Remove LegendElement from pipeline
+        exporter.elements = [e for e in exporter.elements if not isinstance(e, export_mesh_to_pdf.Legend)]
+
+        with tempfile.TemporaryDirectory() as tmpdir:
+            pdf_path = os.path.join(tmpdir, "no_legend.pdf")
+            exporter.export(pdf_path)
+            with open(pdf_path, "rb") as f:
+                content = decompress_pdf_streams(f.read())
+            # X and Y axis text labels from Legend should be absent
+            self.assertNotIn("(X) Tj", content)
+            self.assertNotIn("(Y) Tj", content)
+
 
 if __name__ == '__main__':
     unittest.main()