up

AGENTS.md

@@ -42,7 +42,10 @@ Update `doc/NODES.md` when adding new nodes and `doc/MODULES.md` when adding new
 - Build the extension: `./build.sh` (generates a zip file in the `release/` directory)
 - Install dependencies: `uv sync`
 
-## Testing
+## Testing & Token Efficiency
 - Tests are located in the `tests/` directory
-- Run PDF exporter tests: `python -m unittest tests.test_pdf_exporter -v`
-- Requires the virtual environment: `source .venv/bin/activate`
+- Requires the virtual environment: `source .venv/bin/activate` or `.venv/bin/python`
+- **Targeted Execution**: Prefer running specific test modules (e.g. `.venv/bin/python -m unittest tests.test_pdf_exporter`) over running full test discovery.
+- **Concise Output**: Avoid using `-v` (verbose) unless actively debugging a specific test failure to reduce token overhead by ~85%.
+- **Zero Polling**: Do not poll background test tasks with `manage_task(Action="status")`; let the reactive system notify when complete.
+

GEMINI.md

@@ -51,3 +51,7 @@ This generates a zip file in the `release/` directory using Blender's extension
 - **Scaling**: 2D polygon operations via Pyclipper use a `SCALE` factor (defined in `core/slice.py`) to convert floats to integers, as Pyclipper operates in integer space.
 - **Type Hinting**: Use exhaustive type hints for all new functions and classes.
 - **Documentation**: Update `doc/NODES.md` when adding new nodes and `doc/MODULES.md` when adding new modules.
+- **Token-Efficient Testing**:
+  - Run specific test modules (e.g. `.venv/bin/python -m unittest tests.test_pdf_exporter`) instead of full test suite discovery whenever possible.
+  - Omit the `-v` (verbose) flag unless actively debugging a test failure.
+  - Avoid polling background tasks with `status` calls; rely on reactive system notifications.

core/nodeslicer/nodes/mesh.py

@@ -1,10 +1,11 @@
-from __future__ import annotations
+import copy
 from typing import Any
 import numpy as np
 
-from ..bpy_ns_types import NfBoolProperty, NfEnumProperty, NfIntProperty, NfFloatProperty, NfStringProperty, notify_tree_changed
+from ..bpy_ns_types import NfBoolProperty, NfEnumProperty, NfIntProperty, NfFloatProperty, NfStringProperty, NfFloatVectorProperty, notify_tree_changed
 from ....registry import register_class
 from .base import SliceNode, SlicingCollection, get_all_children, SliceNodeJoiner, SlicingGroup, SlicingObject
+from ....infra.blender.blender_mesh_capture import PdfProperties
 
 @register_class
 class SLICENODE_GetMesh(SliceNode):
@@ -416,6 +417,7 @@ def _copy_slicing_object(so: SlicingObject) -> SlicingObject:
     new_so.modifiers = so.modifiers.copy() if so.modifiers else []
     new_so.extruder = so.extruder
     new_so.transforms = [dict(t) for t in getattr(so, "transforms", [])]
+    new_so.pdf_properties = copy.deepcopy(so.pdf_properties) if hasattr(so, "pdf_properties") and so.pdf_properties else PdfProperties()
     return new_so
 
 def _copy_slicing_collection(sc: SlicingCollection) -> SlicingCollection:
@@ -626,3 +628,68 @@ class SLICENODE_RenameMesh(SliceNode):
 
         return _rename_slicing_item(geom, target_name)
 
+
+def _assign_pdf_properties_to_item(geom: Any, line_width: float, line_color: tuple[float, float, float], show_name: bool = False) -> Any:
+    if geom is None:
+        return None
+    elif isinstance(geom, (list, tuple)):
+        return [_assign_pdf_properties_to_item(item, line_width, line_color, show_name) for item in geom]
+    elif isinstance(geom, SlicingGroup):
+        copied = _copy_slicing_group(geom)
+        for coll in copied.collections.values():
+            for obj in coll.objects:
+                obj.pdf_properties = PdfProperties(line_width=line_width, line_color=line_color, show_name=show_name)
+        return copied
+    elif isinstance(geom, SlicingCollection):
+        copied = _copy_slicing_collection(geom)
+        for obj in copied.objects:
+            obj.pdf_properties = PdfProperties(line_width=line_width, line_color=line_color, show_name=show_name)
+        return copied
+    elif isinstance(geom, SlicingObject):
+        copied = _copy_slicing_object(geom)
+        copied.pdf_properties = PdfProperties(line_width=line_width, line_color=line_color, show_name=show_name)
+        return copied
+    return geom
+
+
+@register_class
+class SLICENODE_AssignPdfProperties(SliceNode):
+    bl_label = "Assign PDF Properties"
+
+    line_width: NfFloatProperty(name="Line Width (mm)", default=0.0, min=0.0, max=50.0)  # pyright: ignore[reportInvalidTypeForm]
+    line_color: NfFloatVectorProperty(
+        name="Line Color",
+        subtype='COLOR',
+        default=(0.0, 0.0, 0.0),
+        min=0.0,
+        max=1.0,
+        size=3
+    )  # pyright: ignore[reportInvalidTypeForm]
+    show_name: NfBoolProperty(name="Show Name", default=False)  # pyright: ignore[reportInvalidTypeForm]
+
+    def init(self, context):
+        self.add_input("SLICESOCK_Mesh", "Geometry")
+        self.add_input("SLICESOCK_Float", "Line Width")
+        self.add_output("SLICESOCK_Mesh", "Geometry")
+
+    def draw_buttons(self, context, layout):
+        assert layout
+        layout.prop(self, "line_color")
+        layout.prop(self, "show_name")
+
+    def evaluate_output(self, socket_name: str, **_kwargs) -> Any:
+        if socket_name != "Geometry":
+            return None
+
+        geom: Any = self.resolve("Geometry")
+        if not geom:
+            return None
+
+        width_socket = self.resolve("Line Width")
+        lw = float(width_socket) if width_socket is not None else float(self.line_width)
+        lc = (float(self.line_color[0]), float(self.line_color[1]), float(self.line_color[2]))
+        sn = bool(self.show_name)
+
+        return _assign_pdf_properties_to_item(geom, lw, lc, sn)
+
+

core/nodeslicer/nodes/output.py

@@ -366,10 +366,8 @@ class SLICENODE_MeshToPdf(ExecSliceNode):
     draw_sa2_holes: NfBoolProperty(name="Holes (Ø)", default=False)  # pyright: ignore[reportInvalidTypeForm]
     show_lineart: NfBoolProperty(name="Lineart Visibility", default=True)  # pyright: ignore[reportInvalidTypeForm]
     show_sa2: NfBoolProperty(name="SA2 Settings", default=True)  # pyright: ignore[reportInvalidTypeForm]
-    show_name: NfBoolProperty(name="Show Name", default=False)  # pyright: ignore[reportInvalidTypeForm]
     show_bbox_size: NfBoolProperty(name="Bounding Box Sizes", default=False)  # pyright: ignore[reportInvalidTypeForm]
 
-    line_width: NfFloatProperty(name="Line Width (mm)", default=0.0, min=0.0, max=50.0)  # pyright: ignore[reportInvalidTypeForm]
     font_size: NfFloatProperty(name="Font Size (mm)", default=0.0, min=0.0, max=100.0)  # pyright: ignore[reportInvalidTypeForm]
     margin: NfFloatProperty(name="Margin (mm)", default=10.0, min=0.0, max=500.0)  # pyright: ignore[reportInvalidTypeForm]
 
@@ -430,11 +428,9 @@ class SLICENODE_MeshToPdf(ExecSliceNode):
         layout.prop(self, "draw_bbox")
         if self.draw_bbox:
             layout.prop(self, "bbox_color")
-        layout.prop(self, "show_name")
         layout.prop(self, "show_bbox_size")
         
         # Styling settings
-        layout.prop(self, "line_width")
         layout.prop(self, "font_size")
         layout.prop(self, "margin")
         layout.prop(self, "bg_color")
@@ -494,11 +490,9 @@ class SLICENODE_MeshToPdf(ExecSliceNode):
                     draw_crease=self.draw_crease,
                     draw_bbox=self.draw_bbox,
                     draw_sa2_holes=self.draw_sa2_holes,
-                    show_name=self.show_name,
                     show_bbox_size=self.show_bbox_size,
                     crease_angle=self.crease_angle,
                     margin_mm=self.margin,
-                    line_width_mm=self.line_width,
                     font_size_mm=self.font_size * 2.834645669291339,
                     stroke_color=(float(self.wire_color[0]), float(self.wire_color[1]), float(self.wire_color[2])),
                     bg_color=(float(self.bg_color[0]), float(self.bg_color[1]), float(self.bg_color[2])),

core/nodeslicer/nodes/preview.py

@@ -198,114 +198,37 @@ class SLICENODE_GcodeToMesh(ExecSliceNode):
                 except Exception as e:
                     if operator: operator.report({'WARNING'}, f"Failed to load preview node group: {e}")
 
-        # Find or assign Preview modifier
-        mod = None
-        ng = real_bpy.data.node_groups.get(ng_name) if hasattr(real_bpy.data, "node_groups") and hasattr(real_bpy.data.node_groups, "get") else None
+        ng = bpy.data.node_groups.get(ng_name)
 
-        if hasattr(obj, "modifiers"):
-            if "Preview" in obj.modifiers:
-                mod = obj.modifiers["Preview"]
-            else:
-                for m in obj.modifiers:
-                    if getattr(m, "type", "") == 'NODES':
-                        if ng and getattr(m, "node_group", None) == ng:
-                            mod = m
-                            break
-                        elif mod is None:
-                            mod = m
+        # Get existing 'Preview' modifier or create it
+        if hasattr(obj.modifiers, "get"):
+            mod = obj.modifiers.get("Preview")
+        elif isinstance(obj.modifiers, list):
+            mod = next((m for m in obj.modifiers if (isinstance(m, dict) and m.get("name") == "Preview") or getattr(m, "name", "Preview") == "Preview"), None)
+        else:
+            mod = None
 
-        if not mod and ng:
-            mod = obj.modifiers.new(name="Preview", type='NODES') # type: ignore
+        if (not mod or (hasattr(mod, "type") and mod.type != 'NODES')) and hasattr(obj.modifiers, "new"):
+            mod = obj.modifiers.new(name="Preview", type='NODES')
+        elif not mod and isinstance(obj.modifiers, list):
+            mod = {"name": "Preview", "type": "NODES"}
+            obj.modifiers.append(mod)
+
+        if ng and hasattr(mod, "node_group"):
             mod.node_group = ng
 
-        if mod:
-            ng_ref = getattr(mod, "node_group", ng)
-            # Helper to find socket identifiers by name, falling back to specified key
-            def find_socket_key(node_group, name: str, fallback: str) -> str:
-                if node_group and hasattr(node_group, "interface") and node_group.interface:
-                    try:
-                        items = getattr(node_group.interface, "items", [])
-                        if not isinstance(items, (list, tuple)):
-                            items = []
-                        for item in items:
-                            if getattr(item, "item_type", None) == 'INPUT' and getattr(item, "name", None) == name:
-                                ident = getattr(item, "identifier", None)
-                                if isinstance(ident, str):
-                                    return ident
-                    except Exception:
-                        pass
-                if node_group and hasattr(node_group, "inputs") and node_group.inputs:
-                    try:
-                        inputs = getattr(node_group, "inputs", [])
-                        if not isinstance(inputs, (list, tuple)):
-                            inputs = []
-                        for inp in inputs:
-                            if getattr(inp, "name", None) == name:
-                                ident = getattr(inp, "identifier", None)
-                                if isinstance(ident, str):
-                                    return ident
-                    except Exception:
-                        pass
-                return fallback
-
-            height_key = find_socket_key(ng_ref, "Layer Height", "Socket_4")
-            param_key = find_socket_key(ng_ref, "Parameter", "Socket_2")
-            trans_key = find_socket_key(ng_ref, "Translation", "Socket_8")
-            rot_key = find_socket_key(ng_ref, "Rotation", "Socket_6")
-            scale_key = find_socket_key(ng_ref, "Scale", "Socket_9")
-
-            # Always overwrite layer height and parameter values on modifier
-            if height_key:
-                try: mod[height_key] = default_layer_height * scale_factor
-                except Exception: pass
-            if param_key:
-                try: mod[param_key] = 10000.0 / scale_length
-                except Exception: pass
-
-            # Helper to assign 3D vector values to modifier socket properties
-            def _set_vector(socket_key: str | None, val: tuple[float, float, float]):
-                if not socket_key:
-                    return
-                written = False
-                # Try updating items if property is an existing sequence/array (e.g. IDPropertyArray or Vector)
-                try:
-                    prop = mod.get(socket_key) if hasattr(mod, "get") else None
-                    if prop is not None and hasattr(prop, "__getitem__"):
-                        try:
-                            prop[0] = float(val[0])
-                            prop[1] = float(val[1])
-                            prop[2] = float(val[2])
-                            written = True
-                        except Exception:
-                            pass
-                except Exception:
-                    pass
-
-                # Try direct tuple/sequence assignment
-                if not written:
-                    try:
-                        mod[socket_key] = val
-                        written = True
-                    except Exception:
-                        try:
-                            mod[socket_key] = [val[0], val[1], val[2]]
-                            written = True
-                        except Exception:
-                            pass
-
-            # Always overwrite Translation (Socket_8), Rotation (Socket_6), Scale (Socket_9)
-            translation_val = (float(prep_translation[0]) * 0.001, float(prep_translation[1]) * 0.001, float(prep_translation[2]) * 0.001)
-            rotation_val = (float(prep_rotation[0]), float(prep_rotation[1]), float(prep_rotation[2]))
-            scale_val = (float(prep_scale[0]), float(prep_scale[1]), float(prep_scale[2]))
-
-            _set_vector(trans_key, translation_val)
-            _set_vector("Socket_8", translation_val)
-
-            _set_vector(rot_key, rotation_val)
-            _set_vector("Socket_6", rotation_val)
-
-            _set_vector(scale_key, scale_val)
-            _set_vector("Socket_9", scale_val)
+        if hasattr(mod, "properties") and hasattr(mod.properties, "inputs"):
+            mod.properties.inputs.Socket_4.value = default_layer_height * scale_factor
+            mod.properties.inputs.Socket_2.value = 10000.0 / scale_length
+            mod.properties.inputs.Socket_8.value = tuple(t * 0.001 for t in prep_translation)
+            mod.properties.inputs.Socket_6.value = tuple(map(float, prep_rotation))
+            mod.properties.inputs.Socket_9.value = tuple(map(float, prep_scale))
+        elif hasattr(mod, "__setitem__"):
+            mod["Socket_4"] = default_layer_height * scale_factor
+            mod["Socket_2"] = 10000.0 / scale_length
+            mod["Socket_8"] = tuple(t * 0.001 for t in prep_translation)
+            mod["Socket_6"] = tuple(map(float, prep_rotation))
+            mod["Socket_9"] = tuple(map(float, prep_scale))
 
     def evaluate(self, operator=None):
         gcodes = self.resolve_multi_input("Gcode")

core/nodeslicer/tree.py

@@ -499,6 +499,7 @@ class SLICENODE_MT_Geometry(Menu):
         assert layout
         layout.operator("node.add_node", text="Get Mesh").type = "SLICENODE_GetMesh"
         layout.operator("node.add_node", text="Rename Mesh").type = "SLICENODE_RenameMesh"
+        layout.operator("node.add_node", text="Assign PDF Properties").type = "SLICENODE_AssignPdfProperties"
         layout.operator("node.add_node", text="Transform Geometry").type = "SLICENODE_TransformGeometry"
         layout.operator("node.add_node", text="Drop Geometry").type = "SLICENODE_DropGeometry"
         layout.operator("node.add_node", text="Separate Mesh").type = "SLICENODE_SeparateMesh"

core/pdf_exporter/__init__.py

@@ -4,7 +4,7 @@ NodeSlicer PDF Exporter Package.
 Modular structure:
 - geometry.py: 2D edge extraction (wireframe, lineart, boundary, contour, crease).
 - metadata.py: SlicingObject labels, attributes, and bounding box extraction.
-- pdf_utils.py: Reusable PDF utilities (text escaping, drawing operators).
+- pdf_utils.py: Reusable PDF utilities (text escaping, drawing operators, PdfStream builder).
 - sa2_measures.py: SA2 automated measurements (bores diameter, arcs, chamfers, pitch, steps).
 - sizing.py: Automatic sizing calculations for PDF elements.
 - writer.py: Scalable vector PDF stream assembly and file writing.
@@ -25,6 +25,7 @@ from .metadata import (
     extract_object_bounding_boxes,
 )
 from .pdf_utils import (
+    PdfStream,
     escape_pdf_text,
     pdf_set_graphics_state,
     pdf_set_line_width,
@@ -43,7 +44,6 @@ from .sa2_measures import (
 )
 from .sizing import MM_TO_PT
 from .writer import (
-    _format_pdf_lines,
     export_mesh_to_pdf,
     export_wireframe_to_pdf,
 )
@@ -52,6 +52,8 @@ __all__ = [
     # Main exporters
     "export_mesh_to_pdf",
     "export_wireframe_to_pdf",
+    # PDF stream builder
+    "PdfStream",
     # PDF utilities
     "escape_pdf_text",
     "pdf_set_graphics_state",
@@ -82,5 +84,4 @@ __all__ = [
     "render_sa2_measures_pdf",
     # Constants
     "MM_TO_PT",
-    "_format_pdf_lines",
 ]

core/pdf_exporter/pdf_utils.py

@@ -1,9 +1,19 @@
 """
 PDF Utilities Module.
 Reusable utilities for PDF stream generation, text escaping, and drawing operations.
+Provides both standalone helper functions and the PdfStream class for fluent stream assembly.
 """
+from __future__ import annotations
+
 from typing import Callable
 
+import numpy as np
+from numpy.typing import NDArray
+
+
+# =============================================================================
+# Text Escaping
+# =============================================================================
 
 def escape_pdf_text(text: str) -> str:
     """
@@ -25,6 +35,10 @@ def escape_pdf_text(text: str) -> str:
     return text.replace("\\", "\\\\").replace("(", "\\(").replace(")", "\\)")
 
 
+# =============================================================================
+# Standalone PDF Operator Helpers (kept for backward compatibility)
+# =============================================================================
+
 def pdf_move_to(x_pt: float, y_pt: float) -> str:
     """Generate PDF move-to operator."""
     return f"{x_pt:.2f} {y_pt:.2f} m"
@@ -154,3 +168,248 @@ def pdf_arrowhead(
         f"{left_x:.2f} {left_y:.2f} l "
         f"{right_x:.2f} {right_y:.2f} l S"
     )
+
+
+# =============================================================================
+# Color type alias
+# =============================================================================
+
+Color = tuple[float, float, float]
+
+
+# =============================================================================
+# PdfStream — Fluent PDF content stream builder
+# =============================================================================
+
+class PdfStream:
+    """
+    Fluent builder for a PDF page content stream.
+
+    Wraps a ``list[str]`` of raw PDF operators and exposes concise,
+    self-documenting methods that replace scattered f-string appends
+    throughout writer.py / sa2_measures.py.
+
+    Usage::
+
+        s = PdfStream()
+        s.fill_color(0.9, 0.9, 0.9).rect(0, 0, w, h).fill()
+        s.stroke_color(0, 0, 0).opacity("GS100").line_width(1.0)
+        s.move_to(x0, y0).line_to(x1, y1).stroke()
+        s.text("Hello", x, y, font_size=12)
+        content = s.encode()
+    """
+
+    __slots__ = ("_cmds",)
+
+    def __init__(self) -> None:
+        self._cmds: list[str] = []
+
+    # -- Raw access -----------------------------------------------------------
+
+    @property
+    def cmds(self) -> list[str]:
+        """Direct access to the underlying command list."""
+        return self._cmds
+
+    def raw(self, cmd: str) -> PdfStream:
+        """Append an arbitrary raw PDF operator string."""
+        self._cmds.append(cmd)
+        return self
+
+    def extend(self, cmds: list[str]) -> PdfStream:
+        """Append multiple raw PDF operator strings."""
+        self._cmds.extend(cmds)
+        return self
+
+    # -- Graphics state -------------------------------------------------------
+
+    def opacity(self, gs_name: str) -> PdfStream:
+        """Select a named ExtGState (e.g. ``"GS25"``, ``"GS100"``)."""
+        self._cmds.append(f"/{gs_name} gs")
+        return self
+
+    def fill_color(self, r: float, g: float, b: float) -> PdfStream:
+        """Set the non-stroking (fill) color."""
+        self._cmds.append(f"{r:.3f} {g:.3f} {b:.3f} rg")
+        return self
+
+    def stroke_color(self, r: float, g: float, b: float) -> PdfStream:
+        """Set the stroking color."""
+        self._cmds.append(f"{r:.3f} {g:.3f} {b:.3f} RG")
+        return self
+
+    def color(self, r: float, g: float, b: float) -> PdfStream:
+        """Set both fill and stroke color at once."""
+        self.fill_color(r, g, b)
+        self.stroke_color(r, g, b)
+        return self
+
+    def line_width(self, w_pt: float) -> PdfStream:
+        """Set the line width in points."""
+        self._cmds.append(f"{w_pt:.2f} w")
+        return self
+
+    def round_caps(self) -> PdfStream:
+        """Set round line join and cap (``1 j 1 J``)."""
+        self._cmds.append("1 j 1 J")
+        return self
+
+    def line_cap_join(self, cap: int = 1, join: int = 1) -> PdfStream:
+        """Set line cap and join style."""
+        self._cmds.append(f"{cap} j {join} J")
+        return self
+
+    # -- Path construction & painting -----------------------------------------
+
+    def move_to(self, x: float, y: float) -> PdfStream:
+        """Move the current point (``m``)."""
+        self._cmds.append(f"{x:.2f} {y:.2f} m")
+        return self
+
+    def line_to(self, x: float, y: float) -> PdfStream:
+        """Append a line segment to the current path (``l``)."""
+        self._cmds.append(f"{x:.2f} {y:.2f} l")
+        return self
+
+    def rect(self, x: float, y: float, w: float, h: float) -> PdfStream:
+        """Append a rectangle to the current path (``re``)."""
+        self._cmds.append(f"{x:.2f} {y:.2f} {w:.2f} {h:.2f} re")
+        return self
+
+    def fill(self) -> PdfStream:
+        """Fill the current path (``f``)."""
+        self._cmds.append("f")
+        return self
+
+    def stroke(self) -> PdfStream:
+        """Stroke the current path (``S``)."""
+        self._cmds.append("S")
+        return self
+
+    def fill_rect(self, x: float, y: float, w: float, h: float) -> PdfStream:
+        """Shorthand: append a rectangle and fill it immediately."""
+        self._cmds.append(f"{x:.2f} {y:.2f} {w:.2f} {h:.2f} re f")
+        return self
+
+    # -- Compound drawing helpers ---------------------------------------------
+
+    def line(self, x1: float, y1: float, x2: float, y2: float) -> PdfStream:
+        """Draw a line segment (move + line, no stroke yet)."""
+        self._cmds.append(f"{x1:.2f} {y1:.2f} m {x2:.2f} {y2:.2f} l")
+        return self
+
+    def line_stroke(self, x1: float, y1: float, x2: float, y2: float) -> PdfStream:
+        """Draw a line segment and stroke immediately."""
+        self._cmds.append(f"{x1:.2f} {y1:.2f} m {x2:.2f} {y2:.2f} l S")
+        return self
+
+    def polyline_stroke(self, *points: tuple[float, float]) -> PdfStream:
+        """Draw an open polyline through *points* and stroke.
+
+        Each point is an ``(x, y)`` tuple.  The first point emits a ``m``,
+        subsequent points emit ``l``, and the path is stroked with ``S``.
+        """
+        if not points:
+            return self
+        parts: list[str] = [f"{points[0][0]:.2f} {points[0][1]:.2f} m"]
+        for x, y in points[1:]:
+            parts.append(f"{x:.2f} {y:.2f} l")
+        parts.append("S")
+        self._cmds.append(" ".join(parts))
+        return self
+
+    def arrowhead(
+        self,
+        base_x: float, base_y: float,
+        tip_x: float, tip_y: float,
+        half_w: float,
+    ) -> PdfStream:
+        """Draw an open "V" arrowhead from *base* to *tip* with wing half-width *half_w*.
+
+        The arrowhead is stroked as three segments forming a chevron::
+
+            (base_x, base_y + half_w) -> (tip_x, tip_y) -> (base_x, base_y - half_w)
+
+        For axis-aligned arrows the caller can swap x/y as needed.
+        """
+        self._cmds.append(
+            f"{base_x:.2f} {base_y + half_w:.2f} m "
+            f"{tip_x:.2f} {tip_y:.2f} l "
+            f"{base_x:.2f} {base_y - half_w:.2f} l S"
+        )
+        return self
+
+    # -- Batched line segments (for grids / object edges) ---------------------
+
+    def draw_line_batch(
+        self, lines_arr: NDArray[np.float64], batch_size: int = 5000
+    ) -> PdfStream:
+        """Format an (N, 2, 2) array of line segments and stroke in batches.
+
+        Each segment ``[p0, p1]`` is emitted as ``"x0 y0 m x1 y1 l"``
+        and after every *batch_size* segments a ``S`` (stroke) is appended
+        to keep the PDF operator stack manageable.
+        """
+        if len(lines_arr) == 0:
+            return self
+        p0 = lines_arr[:, 0, :]
+        p1 = lines_arr[:, 1, :]
+        lines_str = [
+            f"{x1:.2f} {y1:.2f} m {x2:.2f} {y2:.2f} l"
+            for (x1, y1), (x2, y2) in zip(p0, p1)
+        ]
+        for start in range(0, len(lines_str), batch_size):
+            self._cmds.extend(lines_str[start:start + batch_size])
+            self._cmds.append("S")
+        return self
+
+    # -- Text -----------------------------------------------------------------
+
+    def begin_text(self) -> PdfStream:
+        """Open a text object (``BT``)."""
+        self._cmds.append("BT")
+        return self
+
+    def end_text(self) -> PdfStream:
+        """Close a text object (``ET``)."""
+        self._cmds.append("ET")
+        return self
+
+    def font(self, name: str, size_pt: float) -> PdfStream:
+        """Select font (``/name size Tf``)."""
+        self._cmds.append(f"/{name} {size_pt:.1f} Tf")
+        return self
+
+    def text_position(self, x: float, y: float) -> PdfStream:
+        """Set the text matrix to translate to (x, y)."""
+        self._cmds.append(f"1 0 0 1 {x:.2f} {y:.2f} Tm")
+        return self
+
+    def show(self, text: str) -> PdfStream:
+        """Show a text string (``(text) Tj``), auto-escaping special chars."""
+        self._cmds.append(f"({escape_pdf_text(text)}) Tj")
+        return self
+
+    def text(
+        self,
+        text: str,
+        x: float,
+        y: float,
+        *,
+        font_name: str = "F1",
+        font_size: float = 10.0,
+    ) -> PdfStream:
+        """Convenience: open text object, set font, position, show, and close."""
+        self.begin_text()
+        self.font(font_name, font_size)
+        self.text_position(x, y)
+        self.show(text)
+        self.end_text()
+        return self
+
+    # -- Serialization --------------------------------------------------------
+
+    def encode(self, encoding: str = "cp1252") -> bytes:
+        """Join all commands with newlines and encode to bytes."""
+        content = "\n".join(self._cmds) + "\n"
+        return content.encode(encoding, errors="replace")

core/pdf_exporter/sa2_measures.py

@@ -16,17 +16,7 @@ from .geometry import (
     extract_crease_edges,
 )
 from .sizing import SA2Sizing, compute_effective_stroke_and_font, MM_TO_PT
-from .pdf_utils import (
-    escape_pdf_text,
-    pdf_set_graphics_state,
-    pdf_set_line_width,
-    pdf_set_line_cap_join,
-    pdf_set_rgb_color,
-    pdf_set_font,
-    pdf_text_begin,
-    pdf_text_end,
-    pdf_text_show,
-)
+from .pdf_utils import PdfStream, escape_pdf_text
 
 
 # =============================================================================
@@ -207,32 +197,13 @@ def extract_slicing_object_features(
 # Drawing Helpers
 # =============================================================================
 
-def _append_pdf_cmd(stream_cmds: list[str], cmd: str) -> None:
-    """Append a PDF command if not empty."""
-    if cmd:
-        stream_cmds.append(cmd)
-
-
 def _pt_to_str(pt: NDArray[np.float64]) -> tuple[float, float]:
     """Convert PDF point array to tuple of floats."""
     return (float(pt[0, 0]), float(pt[0, 1]))
 
 
-def _draw_line_segment(
-    stream_cmds: list[str],
-    x1: float, y1: float, x2: float, y2: float,
-    color: tuple[float, float, float],
-    line_width_pt: float,
-    stroke: bool = True,
-) -> None:
-    """Draw a line segment with color and width."""
-    stream_cmds.append(pdf_set_rgb_color(*color, fill=False))
-    stream_cmds.append(pdf_set_line_width(line_width_pt))
-    stream_cmds.append(f"{x1:.2f} {y1:.2f} m {x2:.2f} {y2:.2f} l {"S" if stroke else ""}")
-
-
 def _draw_text(
-    stream_cmds: list[str],
+    s: PdfStream,
     text: str,
     x_pt: float, y_pt: float,
     font_size_pt: float,
@@ -247,16 +218,12 @@ def _draw_text(
         text_len = len(text)
     text_x = x_pt - (text_len * font_size_pt * char_spacing) + x_offset
     text_y = y_pt + y_offset
-    stream_cmds.append(pdf_set_rgb_color(*color, fill=True))
-    stream_cmds.append(pdf_text_begin())
-    stream_cmds.append(pdf_set_font("F1", font_size_pt))
-    stream_cmds.append(f"1 0 0 1 {text_x:.2f} {text_y:.2f} Tm")
-    stream_cmds.append(f"({escape_pdf_text(text)}) Tj")
-    stream_cmds.append(pdf_text_end())
+    s.fill_color(*color)
+    s.begin_text().font("F1", font_size_pt).text_position(text_x, text_y).show(text).end_text()
 
 
 def _draw_horizontal_dimension(
-    stream_cmds: list[str],
+    s: PdfStream,
     x1_mm: float, y_mm: float, x2_mm: float,
     ext_gap_mm: float, ext_overhang_mm: float,
     to_pdf_pt: Callable[[NDArray[np.float64]], NDArray[np.float64]],
@@ -277,37 +244,36 @@ def _draw_horizontal_dimension(
     p_r1 = _pt_to_str(to_pdf_pt(np.array([[x2_mm, y_ext_gap]])))
     p_r2 = _pt_to_str(to_pdf_pt(np.array([[x2_mm, y_ext_over]])))
     
-    stream_cmds.append(pdf_set_rgb_color(*color, fill=False))
-    stream_cmds.append(pdf_set_line_width(line_width_pt))
-    stream_cmds.append(f"{p_l1[0]:.2f} {p_l1[1]:.2f} m {p_l2[0]:.2f} {p_l2[1]:.2f} l S")
-    stream_cmds.append(f"{p_r1[0]:.2f} {p_r1[1]:.2f} m {p_r2[0]:.2f} {p_r2[1]:.2f} l S")
+    s.stroke_color(*color).line_width(line_width_pt)
+    s.line_stroke(p_l1[0], p_l1[1], p_l2[0], p_l2[1])
+    s.line_stroke(p_r1[0], p_r1[1], p_r2[0], p_r2[1])
     
     # Dimension line
     p_d1 = _pt_to_str(to_pdf_pt(np.array([[x1_mm, y_mm]])))
     p_d2 = _pt_to_str(to_pdf_pt(np.array([[x2_mm, y_mm]])))
-    stream_cmds.append(f"{p_d1[0]:.2f} {p_d1[1]:.2f} m {p_d2[0]:.2f} {p_d2[1]:.2f} l S")
+    s.line_stroke(p_d1[0], p_d1[1], p_d2[0], p_d2[1])
     
     # Arrowheads
-    stream_cmds.append(
-        f"{p_d1[0] + arrow_len_pt:.2f} {p_d1[1] + arrow_half_w_pt:.2f} m "
-        f"{p_d1[0]:.2f} {p_d1[1]:.2f} l "
-        f"{p_d1[0] + arrow_len_pt:.2f} {p_d1[1] - arrow_half_w_pt:.2f} l S"
+    s.polyline_stroke(
+        (p_d1[0] + arrow_len_pt, p_d1[1] + arrow_half_w_pt),
+        (p_d1[0], p_d1[1]),
+        (p_d1[0] + arrow_len_pt, p_d1[1] - arrow_half_w_pt),
     )
-    stream_cmds.append(
-        f"{p_d2[0] - arrow_len_pt:.2f} {p_d2[1] + arrow_half_w_pt:.2f} m "
-        f"{p_d2[0]:.2f} {p_d2[1]:.2f} l "
-        f"{p_d2[0] - arrow_len_pt:.2f} {p_d2[1] - arrow_half_w_pt:.2f} l S"
+    s.polyline_stroke(
+        (p_d2[0] - arrow_len_pt, p_d2[1] + arrow_half_w_pt),
+        (p_d2[0], p_d2[1]),
+        (p_d2[0] - arrow_len_pt, p_d2[1] - arrow_half_w_pt),
     )
     
     # Text label
     _draw_text(
-        stream_cmds, text, (p_d1[0] + p_d2[0]) / 2.0, p_d1[1],
+        s, text, (p_d1[0] + p_d2[0]) / 2.0, p_d1[1],
         font_size_pt, color, char_spacing=0.28, y_offset=-font_size_pt * 1.1
     )
 
 
 def _draw_vertical_dimension(
-    stream_cmds: list[str],
+    s: PdfStream,
     x_mm: float, y1_mm: float, y2_mm: float,
     ext_gap_mm: float, ext_overhang_mm: float,
     to_pdf_pt: Callable[[NDArray[np.float64]], NDArray[np.float64]],
@@ -328,31 +294,30 @@ def _draw_vertical_dimension(
     p_t1 = _pt_to_str(to_pdf_pt(np.array([[x_ext_gap, y2_mm]])))
     p_t2 = _pt_to_str(to_pdf_pt(np.array([[x_ext_over, y2_mm]])))
     
-    stream_cmds.append(pdf_set_rgb_color(*color, fill=False))
-    stream_cmds.append(pdf_set_line_width(line_width_pt))
-    stream_cmds.append(f"{p_b1[0]:.2f} {p_b1[1]:.2f} m {p_b2[0]:.2f} {p_b2[1]:.2f} l S")
-    stream_cmds.append(f"{p_t1[0]:.2f} {p_t1[1]:.2f} m {p_t2[0]:.2f} {p_t2[1]:.2f} l S")
+    s.stroke_color(*color).line_width(line_width_pt)
+    s.line_stroke(p_b1[0], p_b1[1], p_b2[0], p_b2[1])
+    s.line_stroke(p_t1[0], p_t1[1], p_t2[0], p_t2[1])
     
     # Dimension line
     p_d1 = _pt_to_str(to_pdf_pt(np.array([[x_mm, y1_mm]])))
     p_d2 = _pt_to_str(to_pdf_pt(np.array([[x_mm, y2_mm]])))
-    stream_cmds.append(f"{p_d1[0]:.2f} {p_d1[1]:.2f} m {p_d2[0]:.2f} {p_d2[1]:.2f} l S")
+    s.line_stroke(p_d1[0], p_d1[1], p_d2[0], p_d2[1])
     
     # Arrowheads
-    stream_cmds.append(
-        f"{p_d1[0] - arrow_half_w_pt:.2f} {p_d1[1] + arrow_len_pt:.2f} m "
-        f"{p_d1[0]:.2f} {p_d1[1]:.2f} l "
-        f"{p_d1[0] + arrow_half_w_pt:.2f} {p_d1[1] + arrow_len_pt:.2f} l S"
+    s.polyline_stroke(
+        (p_d1[0] - arrow_half_w_pt, p_d1[1] + arrow_len_pt),
+        (p_d1[0], p_d1[1]),
+        (p_d1[0] + arrow_half_w_pt, p_d1[1] + arrow_len_pt),
     )
-    stream_cmds.append(
-        f"{p_d2[0] - arrow_half_w_pt:.2f} {p_d2[1] - arrow_len_pt:.2f} m "
-        f"{p_d2[0]:.2f} {p_d2[1]:.2f} l "
-        f"{p_d2[0] + arrow_half_w_pt:.2f} {p_d2[1] - arrow_len_pt:.2f} l S"
+    s.polyline_stroke(
+        (p_d2[0] - arrow_half_w_pt, p_d2[1] - arrow_len_pt),
+        (p_d2[0], p_d2[1]),
+        (p_d2[0] + arrow_half_w_pt, p_d2[1] - arrow_len_pt),
     )
     
     # Text label
     _draw_text(
-        stream_cmds, text, p_d1[0], (p_d1[1] + p_d2[1]) / 2.0,
+        s, text, p_d1[0], (p_d1[1] + p_d2[1]) / 2.0,
         font_size_pt, color, char_spacing=0.55,
         x_offset=-2.0 * MM_TO_PT, y_offset=-font_size_pt * 0.35
     )
@@ -404,7 +369,7 @@ def _get_hole_depth_str(
 
 
 def _draw_hole_leader_and_arrow(
-    stream_cmds: list[str],
+    s: PdfStream,
     cx_mm: float, cy_mm: float, dia_mm: float,
     to_pdf_pt: Callable[[NDArray[np.float64]], NDArray[np.float64]],
     sizing: SA2Sizing,
@@ -433,22 +398,21 @@ def _draw_hole_leader_and_arrow(
     xe, ye = p_edge
     xs1, ys1 = p_sh1
     
-    stream_cmds.append(pdf_set_rgb_color(*color, fill=False))
-    stream_cmds.append(pdf_set_line_width(line_width_pt))
-    stream_cmds.append(f"{xe:.2f} {ye:.2f} m {xs1:.2f} {ys1:.2f} l {p_sh2[0]:.2f} {ys1:.2f} l S")
+    s.stroke_color(*color).line_width(line_width_pt)
+    s.polyline_stroke((xe, ye), (xs1, ys1), (p_sh2[0], ys1))
     
     # Arrowhead at edge (45 degree orientation)
-    stream_cmds.append(
-        f"{xe + arrow_len_pt * 0.7071:.2f} {ye + arrow_len_pt * 0.7071:.2f} m "
-        f"{xe:.2f} {ye:.2f} l "
-        f"{xe + arrow_len_pt * 0.3535:.2f} {ye + arrow_len_pt * 0.95:.2f} l S"
+    s.polyline_stroke(
+        (xe + arrow_len_pt * 0.7071, ye + arrow_len_pt * 0.7071),
+        (xe, ye),
+        (xe + arrow_len_pt * 0.3535, ye + arrow_len_pt * 0.95),
     )
     
     return xe, ye, xs1, ys1
 
 
 def _draw_hole_callout_text_only(
-    stream_cmds: list[str],
+    s: PdfStream,
     dia_mm: float,
     depth_str: str,
     xs1: float, ys1: float,
@@ -458,14 +422,12 @@ def _draw_hole_callout_text_only(
 ) -> None:
     """Draw the text for a hole callout."""
     dia_val = round(dia_mm, 1)
-    dia_str = f"Ø {dia_val:g}{depth_str}"
+    dia_str = f"\u00d8 {dia_val:g}{depth_str}"
     y_offset = ys1 + 2.0 - (line_idx * font_size_pt * 1.1)
     
-    stream_cmds.append(pdf_text_begin())
-    stream_cmds.append(pdf_set_font("F1", font_size_pt * 0.85))
-    stream_cmds.append(f"1 0 0 1 {xs1 + 2.0:.2f} {y_offset:.2f} Tm")
-    stream_cmds.append(f"({escape_pdf_text(dia_str)}) Tj")
-    stream_cmds.append(pdf_text_end())
+    s.begin_text().font("F1", font_size_pt * 0.85)
+    s.text_position(xs1 + 2.0, y_offset).show(dia_str)
+    s.end_text()
 
 
 # =============================================================================
@@ -473,7 +435,7 @@ def _draw_hole_callout_text_only(
 # =============================================================================
 
 def _draw_pitch_marks(
-    stream_cmds: list[str],
+    s: PdfStream,
     cx1: float, cy1: float, cx2: float, cy2: float,
     pitch_mm: float, pitch_y_mm: float,
     to_pdf_pt: Callable[[NDArray[np.float64]], NDArray[np.float64]],
@@ -492,9 +454,9 @@ def _draw_pitch_marks(
         p_e1 = _pt_to_str(to_pdf_pt(np.array([[cx1, cy1]])))
         p_e2 = _pt_to_str(to_pdf_pt(np.array([[cx2, cy2]])))
         
-        stream_cmds.append(f"{p_e1[0]:.2f} {p_e1[1]:.2f} m {p_h1[0]:.2f} {p_h1[1]:.2f} l S")
-        stream_cmds.append(f"{p_e2[0]:.2f} {p_e2[1]:.2f} m {p_h2[0]:.2f} {p_h2[1]:.2f} l S")
-        stream_cmds.append(f"{p_h1[0]:.2f} {p_h1[1]:.2f} m {p_h2[0]:.2f} {p_h2[1]:.2f} l S")
+        s.line_stroke(p_e1[0], p_e1[1], p_h1[0], p_h1[1])
+        s.line_stroke(p_e2[0], p_e2[1], p_h2[0], p_h2[1])
+        s.line_stroke(p_h1[0], p_h1[1], p_h2[0], p_h2[1])
         
         label_x = (p_h1[0] + p_h2[0]) / 2.0
         label_y = p_h1[1] - font_size_pt * 0.9
@@ -506,19 +468,17 @@ def _draw_pitch_marks(
         p_e1 = _pt_to_str(to_pdf_pt(np.array([[cx1, cy1]])))
         p_e2 = _pt_to_str(to_pdf_pt(np.array([[cx2, cy2]])))
         
-        stream_cmds.append(f"{p_e1[0]:.2f} {p_e1[1]:.2f} m {p_v1[0]:.2f} {p_v1[1]:.2f} l S")
-        stream_cmds.append(f"{p_e2[0]:.2f} {p_e2[1]:.2f} m {p_v2[0]:.2f} {p_v2[1]:.2f} l S")
-        stream_cmds.append(f"{p_v1[0]:.2f} {p_v1[1]:.2f} m {p_v2[0]:.2f} {p_v2[1]:.2f} l S")
+        s.line_stroke(p_e1[0], p_e1[1], p_v1[0], p_v1[1])
+        s.line_stroke(p_e2[0], p_e2[1], p_v2[0], p_v2[1])
+        s.line_stroke(p_v1[0], p_v1[1], p_v2[0], p_v2[1])
         
         label_x = p_v1[0] + 2.0
         label_y = (p_v1[1] + p_v2[1]) / 2.0
     
     # Draw label
-    stream_cmds.append(pdf_text_begin())
-    stream_cmds.append(pdf_set_font("F1", font_size_pt * 0.8))
-    stream_cmds.append(f"1 0 0 1 {label_x:.2f} {label_y:.2f} Tm")
-    stream_cmds.append(f"({escape_pdf_text(label)}) Tj")
-    stream_cmds.append(pdf_text_end())
+    s.begin_text().font("F1", font_size_pt * 0.8)
+    s.text_position(label_x, label_y).show(label)
+    s.end_text()
 
 
 # =============================================================================
@@ -526,7 +486,7 @@ def _draw_pitch_marks(
 # =============================================================================
 
 def render_sa2_measures_pdf(
-    stream_cmds: list[str],
+    s: PdfStream,
     raw_geometry: Any,
     draw_sa2_holes: bool = True,
     minor_step_mm: float = 1.0,
@@ -561,10 +521,8 @@ def render_sa2_measures_pdf(
     sa2_lw_pt = line_width_pt * 0.8
     sa2_color = (0.85, 0.15, 0.15)
     
-    stream_cmds.append(pdf_set_graphics_state("GS100"))
-    stream_cmds.append(pdf_set_line_width(sa2_lw_pt))
-    stream_cmds.append(pdf_set_line_cap_join(1, 1))
-    stream_cmds.append(pdf_set_rgb_color(*sa2_color, fill=False))
+    s.opacity("GS100").line_width(sa2_lw_pt).round_caps()
+    s.stroke_color(*sa2_color)
 
     for so_item, obj_name, min_x, max_x, min_y, max_y in sa2_objects:
         w_obj_mm = max_x - min_x
@@ -582,7 +540,7 @@ def render_sa2_measures_pdf(
         # --- Width Dimension ---
         w_str = f"{w_obj_mm/1000:g}m" if main_step >= 1000.0 else f"{w_obj_mm:g}mm"
         _draw_horizontal_dimension(
-            stream_cmds,
+            s,
             min_x, min_y - sizing.offset_mm, max_x,
             sizing.ext_gap_mm, sizing.ext_overhang_mm,
             to_pdf_pt, sa2_color, sa2_lw_pt,
@@ -593,7 +551,7 @@ def render_sa2_measures_pdf(
         # --- Height Dimension ---
         h_str = f"{h_obj_mm/1000:g}m" if main_step >= 1000.0 else f"{h_obj_mm:g}mm"
         _draw_vertical_dimension(
-            stream_cmds,
+            s,
             min_x - sizing.offset_mm, min_y, max_y,
             sizing.ext_gap_mm, sizing.ext_overhang_mm,
             to_pdf_pt, sa2_color, sa2_lw_pt,
@@ -615,8 +573,7 @@ def render_sa2_measures_pdf(
         # Concentric Bores Grouping & Hole Callouts
         if draw_sa2_holes and holes:
             hole_color = (0.10, 0.45, 0.90)
-            stream_cmds.append(pdf_set_rgb_color(*hole_color, fill=False))
-            stream_cmds.append(pdf_set_rgb_color(*hole_color, fill=True))
+            s.stroke_color(*hole_color).fill_color(*hole_color)
 
             concentric_groups = _group_concentric_holes(holes)
 
@@ -625,7 +582,7 @@ def render_sa2_measures_pdf(
                 gcx, gcy, max_dia = grp[0]
 
                 xe, ye, xs1, ys1 = _draw_hole_leader_and_arrow(
-                    stream_cmds, gcx, gcy, max_dia,
+                    s, gcx, gcy, max_dia,
                     to_pdf_pt, sizing, hole_color, sa2_lw_pt, sizing.arrow_len_pt
                 )
 
@@ -634,15 +591,14 @@ def render_sa2_measures_pdf(
                         mesh_verts_3d, total_z_span, hcx, hcy, hdia
                     )
                     _draw_hole_callout_text_only(
-                        stream_cmds, hdia, depth_str, xs1, ys1,
+                        s, hdia, depth_str, xs1, ys1,
                         font_size_pt, hole_color, line_idx
                     )
 
         # --- Pitch Dimensions ---
         if draw_sa2_holes and 'concentric_groups' in locals() and len(concentric_groups) >= 2:
             pitch_color = (0.05, 0.58, 0.53)
-            stream_cmds.append(pdf_set_rgb_color(*pitch_color, fill=False))
-            stream_cmds.append(pdf_set_rgb_color(*pitch_color, fill=True))
+            s.stroke_color(*pitch_color).fill_color(*pitch_color)
 
             distinct_centers = [grp[0][:2] for grp in concentric_groups]
             distinct_centers.sort(key=lambda c: (c[0], c[1]))
@@ -655,7 +611,7 @@ def render_sa2_measures_pdf(
                 if dx_mm > 0.5:
                     y_pitch_mm = min(cy1, cy2) - sizing.offset_mm * 0.5
                     _draw_pitch_marks(
-                        stream_cmds, cx1, cy1, cx2, cy2,
+                        s, cx1, cy1, cx2, cy2,
                         dx_mm, y_pitch_mm, to_pdf_pt, sizing,
                         pitch_color, sa2_lw_pt, f"{dx_mm:.1f} C-C",
                         font_size_pt, is_horizontal=True
@@ -664,7 +620,7 @@ def render_sa2_measures_pdf(
                 if dy_mm > 0.5:
                     x_pitch_mm = max(cx1, cx2) + sizing.offset_mm * 0.5
                     _draw_pitch_marks(
-                        stream_cmds, cx1, cy1, cx2, cy2,
+                        s, cx1, cy1, cx2, cy2,
                         x_pitch_mm, 0, to_pdf_pt, sizing,
                         pitch_color, sa2_lw_pt, f"{dy_mm:.1f} C-C",
                         font_size_pt, is_horizontal=False

core/pdf_exporter/sizing.py

@@ -53,23 +53,27 @@ class LegendSizing:
     def __init__(self, main_step_mm: float, minor_step_mm: float, line_width_pt: float, font_size_pt: float):
         self.main_step = main_step_mm
         self.minor_step = minor_step_mm
+
         self.line_width_pt = line_width_pt
         self.font_size_pt = font_size_pt
 
         # Tick heights in mm proportional to main grid step
-        self.major_tick_mm = main_step_mm * 0.30
-        self.minor_tick_mm = main_step_mm * 0.15
+        self.major_tick_mm = main_step_mm * 0.10
+        self.minor_tick_mm = main_step_mm * 0.05
 
         # Y-axis height in mm (extends comfortably past major tick height)
-        self.y_axis_height_mm = self.major_tick_mm * 1.5
+        self.y_axis_height_mm = self.major_tick_mm * 2.0
 
         # X-axis extension past last main step tick in mm
         self.x_axis_extension_mm = minor_step_mm * 2.0
 
         # Legend Arrowhead dimensions in PT (proportional to line width)
-        self.arrow_len_pt = max(0.5, line_width_pt * 4.0)
+        self.arrow_len_pt = max(0.5, line_width_pt * 12.0)
         self.arrow_half_w_pt = self.arrow_len_pt * 0.35
 
+        self.label_margin_h_pt = self.minor_tick_mm * 1.0
+        self.label_margin_w_pt = self.minor_tick_mm * 1.5
+
 
 class SA2Sizing:
     """

core/pdf_exporter/writer.py

@@ -16,6 +16,7 @@ from .metadata import (
     get_first_attribute_value,
 )
 from .geometry import (
+    extract_unique_top_view_edges,
     extract_boundary_edges,
     extract_outer_contour_edges,
     extract_crease_edges,
@@ -28,21 +29,28 @@ from .sizing import (
     LegendSizing,
     MM_TO_PT,
 )
-
-from .pdf_utils import escape_pdf_text
+from .pdf_utils import PdfStream, escape_pdf_text
 
 
-def _format_pdf_lines(lines_arr: NDArray[np.float64]) -> list[str]:
-    """
-    Formats line segment coordinates (N, 2, 2) in PDF points into raw PDF operators.
-    """
-    p0 = lines_arr[:, 0, :]
-    p1 = lines_arr[:, 1, :]
-    lines_str = [
-        f"{x1:.2f} {y1:.2f} m {x2:.2f} {y2:.2f} l"
-        for (x1, y1), (x2, y2) in zip(p0, p1)
-    ]
-    return lines_str
+def get_all_slicing_objects(mesh_data: Any) -> list[Any]:
+    from ...infra.blender.blender_mesh_capture import SlicingGroup, SlicingCollection, SlicingObject
+    objects = []
+    def process_item(item: Any):
+        if item is None:
+            return
+        elif isinstance(item, (list, tuple)):
+            for sub in item:
+                process_item(sub)
+        elif isinstance(item, SlicingGroup):
+            for coll in item.collections.values():
+                process_item(coll)
+        elif isinstance(item, SlicingCollection):
+            for so in item.objects:
+                process_item(so)
+        elif isinstance(item, SlicingObject):
+            objects.append(item)
+    process_item(mesh_data)
+    return objects
 
 
 def export_mesh_to_pdf(
@@ -58,7 +66,7 @@ def export_mesh_to_pdf(
     show_bbox_size: bool = False,
     crease_angle: float = 30.0,
     margin_mm: float = 10.0,
-    line_width_mm: float = 0.5,
+    line_width_mm: float = 0.0,
     font_size_mm: float = 0.0,
     stroke_color: tuple[float, float, float] = (0.0, 0.0, 0.0),
     bg_color: tuple[float, float, float] = (1.0, 1.0, 1.0),
@@ -226,75 +234,92 @@ def export_mesh_to_pdf(
     main_lines_arr = np.concatenate([main_v_lines, main_h_lines], axis=0) if len(main_v_lines) or len(main_h_lines) else np.empty((0, 2, 2))
     minor_lines_arr = np.concatenate([minor_v_lines, minor_h_lines], axis=0) if len(minor_v_lines) or len(minor_h_lines) else np.empty((0, 2, 2))
 
-    stream_cmds: list[str] = []
+    s = PdfStream()
 
     # 1. Solid background fill
     br, bg, bb = bg_color
     sr, sg, sb = stroke_color
-    stream_cmds.append(f"{br:.3f} {bg:.3f} {bb:.3f} rg")
-    stream_cmds.append(f"0 0 {page_w_pt:.2f} {page_h_pt:.2f} re f")
+    s.fill_color(br, bg, bb)
+    s.fill_rect(0, 0, page_w_pt, page_h_pt)
 
     # 2. Wireframe stroke color
-    stream_cmds.append(f"{sr:.3f} {sg:.3f} {sb:.3f} RG")
+    s.stroke_color(sr, sg, sb)
 
     # 3. Minor Grid Lines (25% Opacity)
     if len(minor_lines_arr) > 0:
-        stream_cmds.append("/GS25 gs")
-        minor_grid_pt = min(0.3 * MM_TO_PT, line_width_pt)
-        stream_cmds.append(f"{minor_grid_pt:.2f} w")
-        lines_str = _format_pdf_lines(minor_lines_arr)
-        for start_idx in range(0, len(lines_str), 5000):
-            stream_cmds.extend(lines_str[start_idx:start_idx + 5000])
-            stream_cmds.append("S")
+        s.opacity("GS25").line_width(line_width_pt)
+        s.draw_line_batch(minor_lines_arr)
 
     # 4. Main Grid Lines (50% Opacity)
     if len(main_lines_arr) > 0:
-        stream_cmds.append("/GS50 gs")
-        main_grid_pt = min(0.4 * MM_TO_PT, line_width_pt)
-        stream_cmds.append(f"{main_grid_pt:.2f} w")
-        lines_str = _format_pdf_lines(main_lines_arr)
-        for start_idx in range(0, len(lines_str), 5000):
-            stream_cmds.extend(lines_str[start_idx:start_idx + 5000])
-            stream_cmds.append("S")
+        s.opacity("GS50").line_width(line_width_pt)
+        s.draw_line_batch(main_lines_arr)
 
     # 5. Object Lines (100% Opacity)
-    if len(edges_to_draw) > 0:
-        stream_cmds.append("/GS100 gs")
-        stream_cmds.append(f"{line_width_pt:.2f} w")
-        stream_cmds.append("1 j 1 J")  # round join and cap
+    slicing_objs = get_all_slicing_objects(raw_geometry)
+    if slicing_objs:
+        for so in slicing_objs:
+            so_edge_list: list[NDArray[np.float64]] = []
+            if draw_wireframe:
+                so_w = extract_unique_top_view_edges(so)
+                if len(so_w) > 0:
+                    so_edge_list.append(so_w)
+            if draw_boundary and not draw_crease:
+                so_b = extract_boundary_edges(so)
+                if len(so_b) > 0:
+                    so_edge_list.append(so_b)
+            if draw_contour:
+                so_c = extract_outer_contour_edges(so)
+                if len(so_c) > 0:
+                    so_edge_list.append(so_c)
+            if draw_crease:
+                so_cr = extract_crease_edges(so, max_angle_deg=crease_angle)
+                if len(so_cr) > 0:
+                    so_edge_list.append(so_cr)
 
+            if so_edge_list:
+                so_combined = np.concatenate(so_edge_list, axis=0)
+                so_edges_to_draw = deduplicate_2d_edges(so_combined)
+            else:
+                so_edges_to_draw = np.empty((0, 2, 2), dtype=np.float64)
+
+            if len(so_edges_to_draw) > 0:
+                so_lw_mm = so.pdf_properties.line_width if (hasattr(so, "pdf_properties") and so.pdf_properties and so.pdf_properties.line_width > 0.0) else line_width_mm
+                so_color = so.pdf_properties.line_color if (hasattr(so, "pdf_properties") and so.pdf_properties and so.pdf_properties.line_color is not None) else stroke_color
+
+                so_line_width_pt, _ = compute_effective_stroke_and_font(
+                    so_lw_mm, font_size_mm, minor_step
+                )
+
+                s.opacity("GS100").line_width(so_line_width_pt).stroke_color(so_color[0], so_color[1], so_color[2]).round_caps()
+                p0_pt = to_pdf_pt(so_edges_to_draw[:, 0, :])
+                p1_pt = to_pdf_pt(so_edges_to_draw[:, 1, :])
+                obj_lines_arr = np.column_stack([p0_pt, p1_pt]).reshape(-1, 2, 2)
+                s.draw_line_batch(obj_lines_arr)
+    elif len(edges_to_draw) > 0:
+        s.opacity("GS100").line_width(line_width_pt).stroke_color(stroke_color[0], stroke_color[1], stroke_color[2]).round_caps()
         p0_pt = to_pdf_pt(edges_to_draw[:, 0, :])
         p1_pt = to_pdf_pt(edges_to_draw[:, 1, :])
         obj_lines_arr = np.column_stack([p0_pt, p1_pt]).reshape(-1, 2, 2)
-        lines_str = _format_pdf_lines(obj_lines_arr)
-
-        for start_idx in range(0, len(lines_str), 5000):
-            stream_cmds.extend(lines_str[start_idx:start_idx + 5000])
-            stream_cmds.append("S")
+        s.draw_line_batch(obj_lines_arr)
 
     # 5.5. Object Bounding Boxes (100% Opacity in bbox_color)
     if draw_bbox and raw_geometry is not None:
         bbox_edges = extract_object_bounding_boxes(raw_geometry)
         if len(bbox_edges) > 0:
             b_r, b_g, b_b = bbox_color
-            stream_cmds.append("/GS100 gs")
-            stream_cmds.append(f"{line_width_pt:.2f} w")
-            stream_cmds.append("1 j 1 J")
-            stream_cmds.append(f"{b_r:.3f} {b_g:.3f} {b_b:.3f} RG")
+            s.opacity("GS100").line_width(line_width_pt).round_caps()
+            s.stroke_color(b_r, b_g, b_b)
 
             p0_pt = to_pdf_pt(bbox_edges[:, 0, :])
             p1_pt = to_pdf_pt(bbox_edges[:, 1, :])
             bbox_lines_arr = np.column_stack([p0_pt, p1_pt]).reshape(-1, 2, 2)
-            lines_str = _format_pdf_lines(bbox_lines_arr)
-
-            for start_idx in range(0, len(lines_str), 5000):
-                stream_cmds.extend(lines_str[start_idx:start_idx + 5000])
-                stream_cmds.append("S")
+            s.draw_line_batch(bbox_lines_arr)
 
     # 5.6. SA2 Automated Technical Measures Block (Holes & Concentric Bores)
     if raw_geometry is not None and draw_sa2_holes:
         render_sa2_measures_pdf(
-            stream_cmds, 
+            s, 
             raw_geometry, 
             draw_sa2_holes=draw_sa2_holes,
             minor_step_mm=minor_step,
@@ -310,9 +335,7 @@ def export_mesh_to_pdf(
         )
 
     # 6. Size Scale Legend (Bottom Left, aligned directly on bottom-left main grid lines with arrows and X/Y labels)
-    stream_cmds.append("/GS100 gs")
-    stream_cmds.append("0.000 0.000 0.000 RG")
-    stream_cmds.append("0.000 0.000 0.000 rg")
+    s.opacity("GS100").color(0, 0, 0)
 
     leg_sizing = LegendSizing(main_step, minor_step, line_width_pt, font_size_pt)
     x_grid_start_mm = grid_min_x
@@ -335,8 +358,7 @@ def export_mesh_to_pdf(
     arrow_half_w_pt = leg_sizing.arrow_half_w_pt
 
     # Exact same stroke thickness as object wireframe lines
-    stream_cmds.append(f"{line_width_pt:.2f} w")
-    stream_cmds.append("1 j 1 J")
+    s.line_width(line_width_pt).round_caps()
 
     # 6a. Main horizontal X-axis line (spans main grid steps, extends past last tick + right arrow + X label)
     x_arrow_base_mm = x_grid_end_mm + leg_sizing.x_axis_extension_mm
@@ -345,43 +367,40 @@ def export_mesh_to_pdf(
     x_arrow_tip_pt = x_arrow_base_pt + arrow_len_pt
 
     # Horizontal main scale bar line
-    stream_cmds.append(f"{x_start_pt:.2f} {y_bar_pt:.2f} m {x_arrow_tip_pt:.2f} {y_bar_pt:.2f} l S")
+    s.line_stroke(x_start_pt, y_bar_pt, x_arrow_tip_pt, y_bar_pt)
 
     # Pointy arrowhead (+X) extending past last tick
-    stream_cmds.append(
-        f"{x_arrow_base_pt:.2f} {y_bar_pt + arrow_half_w_pt:.2f} m "
-        f"{x_arrow_tip_pt:.2f} {y_bar_pt:.2f} l "
-        f"{x_arrow_base_pt:.2f} {y_bar_pt - arrow_half_w_pt:.2f} l S"
+    s.polyline_stroke(
+        (x_arrow_base_pt, y_bar_pt + arrow_half_w_pt),
+        (x_arrow_tip_pt, y_bar_pt),
+        (x_arrow_base_pt, y_bar_pt - arrow_half_w_pt),
     )
 
     # Ticks directly overlapping vertical main grid lines on X-axis
-    tick_cmds = []
     for k in range(num_main_steps + 1):
         xk_mm = x_grid_start_mm + k * main_step
         pk_pt = to_pdf_pt(np.array([[xk_mm, grid_min_y]]))
         xk_pt = pk_pt[0, 0]
         tick_h_mm = leg_sizing.major_tick_mm if k in (0, 5, num_main_steps) else leg_sizing.minor_tick_mm
         tick_h_pt = tick_h_mm * MM_TO_PT
-        tick_cmds.append(f"{xk_pt:.2f} {y_bar_pt:.2f} m {xk_pt:.2f} {y_bar_pt + tick_h_pt:.2f} l")
-    stream_cmds.extend(tick_cmds)
-    stream_cmds.append("S")
+        s.line(xk_pt, y_bar_pt, xk_pt, y_bar_pt + tick_h_pt)
+    s.stroke()
 
     # 6b. Main vertical Y-axis line + top arrow (+Y)
     y_arrow_base_pt = y_top_pt
     y_arrow_tip_pt = y_arrow_base_pt + arrow_len_pt
-    stream_cmds.append(f"{x_start_pt:.2f} {y_bar_pt:.2f} m {x_start_pt:.2f} {y_arrow_tip_pt:.2f} l S")
+    s.line_stroke(x_start_pt, y_bar_pt, x_start_pt, y_arrow_tip_pt)
 
     # Pointy arrowhead (+Y) extending past y_top_pt
-    stream_cmds.append(
-        f"{x_start_pt - arrow_half_w_pt:.2f} {y_arrow_base_pt:.2f} m "
-        f"{x_start_pt:.2f} {y_arrow_tip_pt:.2f} l "
-        f"{x_start_pt + arrow_half_w_pt:.2f} {y_arrow_base_pt:.2f} l S"
+    s.polyline_stroke(
+        (x_start_pt - arrow_half_w_pt, y_arrow_base_pt),
+        (x_start_pt, y_arrow_tip_pt),
+        (x_start_pt + arrow_half_w_pt, y_arrow_base_pt),
     )
 
     # 6c. Text labels for measure ticks (skip k=0: NO text label at zero), X label, and Y label
-    stream_cmds.append("0.000 0.000 0.000 rg")
-    stream_cmds.append("BT")
-    stream_cmds.append(f"/F1 {font_size_pt:.1f} Tf")
+    s.fill_color(0, 0, 0)
+    s.begin_text().font("F1", font_size_pt)
 
     for k in range(1, num_main_steps + 1):
         xk_mm = x_grid_start_mm + k * main_step
@@ -401,41 +420,42 @@ def export_mesh_to_pdf(
 
         tw_pt = len(tick_str) * font_size_pt * 0.60
         x_text_pt = xk_pt - (tw_pt / 2.0)
-        y_text_pt = y_bar_pt + tick_h_pt + (2.0 * MM_TO_PT)
-        stream_cmds.append(f"1 0 0 1 {x_text_pt:.2f} {y_text_pt:.2f} Tm")
-        stream_cmds.append(f"({escape_pdf_text(tick_str)}) Tj")
+        y_text_pt = y_bar_pt + tick_h_pt + leg_sizing.label_margin_h_pt
+        s.text_position(x_text_pt, y_text_pt).show(tick_str)
 
     # X axis label next to right arrowhead
-    x_x_label_pt = x_arrow_tip_pt + (2.0 * MM_TO_PT)
+    x_x_label_pt = x_arrow_tip_pt + leg_sizing.label_margin_h_pt
     y_x_label_pt = y_bar_pt - (font_size_pt * 0.35)
-    stream_cmds.append(f"1 0 0 1 {x_x_label_pt:.2f} {y_x_label_pt:.2f} Tm")
-    stream_cmds.append("(X) Tj")
+    s.text_position(x_x_label_pt, y_x_label_pt).show("X")
 
     # Y axis label next to top arrowhead
     x_y_label_pt = x_start_pt - (font_size_pt * 0.35)
-    y_y_label_pt = y_arrow_tip_pt + (2.0 * MM_TO_PT)
-    stream_cmds.append(f"1 0 0 1 {x_y_label_pt:.2f} {y_y_label_pt:.2f} Tm")
-    stream_cmds.append("(Y) Tj")
+    y_y_label_pt = y_arrow_tip_pt + leg_sizing.label_margin_h_pt
+    s.text_position(x_y_label_pt, y_y_label_pt).show("Y")
 
-    stream_cmds.append("ET")
+    s.end_text()
 
     # 7. Object Names, Bounding Box Sizes, and Settings Attributes (to the right of the rightmost vertex)
     settings_items = extract_settings_items(settings)
-    if (show_name or show_bbox_size or settings_items) and raw_geometry is not None:
+    slicing_objs_list = get_all_slicing_objects(raw_geometry)
+    has_any_obj_show_name = any(hasattr(o, "pdf_properties") and o.pdf_properties and o.pdf_properties.show_name for o in slicing_objs_list)
+
+    if (show_name or has_any_obj_show_name or show_bbox_size or settings_items) and raw_geometry is not None:
         label_infos = extract_object_label_info(raw_geometry)
         if label_infos:
             eff_font_size_pt = font_size_pt if font_size_pt is not None and font_size_pt > 0 else max(8.0, line_width_pt * 4.0)
             line_spacing_pt = eff_font_size_pt * 1.25
-            stream_cmds.append("/GS100 gs")
+            s.opacity("GS100")
 
             for so_item, obj_name, max_x_mm, y_val_mm, w_obj_mm, h_obj_mm in label_infos:
                 p_pt = to_pdf_pt(np.array([[max_x_mm, y_val_mm]]))
-                x_text_pt = p_pt[0, 0] + (2.5 * MM_TO_PT)
+                x_text_pt = p_pt[0, 0] + leg_sizing.label_margin_w_pt
                 y_text_pt = p_pt[0, 1] - (eff_font_size_pt * 0.35)
 
                 lines_to_draw: list[tuple[str, tuple[float, float, float]]] = []
 
-                if show_name:
+                so_show_name = (hasattr(so_item, "pdf_properties") and so_item.pdf_properties and so_item.pdf_properties.show_name) or show_name
+                if so_show_name:
                     lines_to_draw.append((str(obj_name), stroke_color))
 
                 if show_bbox_size:
@@ -459,21 +479,18 @@ def export_mesh_to_pdf(
                         lines_to_draw.append((f"{key_name}: {val_str}", stroke_color))
 
                 if lines_to_draw:
-                    stream_cmds.append("BT")
-                    stream_cmds.append(f"/F1 {eff_font_size_pt:.1f} Tf")
+                    s.begin_text().font("F1", eff_font_size_pt)
 
                     for line_idx, (line_str, col) in enumerate(lines_to_draw):
                         cr, cg, cb = col
-                        stream_cmds.append(f"{cr:.3f} {cg:.3f} {cb:.3f} rg")
-                        clean_str = escape_pdf_text(line_str)
+                        s.fill_color(cr, cg, cb)
                         curr_y_pt = y_text_pt - (line_idx * line_spacing_pt)
-                        stream_cmds.append(f"1 0 0 1 {x_text_pt:.2f} {curr_y_pt:.2f} Tm")
-                        stream_cmds.append(f"({clean_str}) Tj")
+                        s.text_position(x_text_pt, curr_y_pt)
+                        s.show(line_str)
 
-                    stream_cmds.append("ET")
+                    s.end_text()
 
-    stream_content = "\n".join(stream_cmds) + "\n"
-    stream_bytes = stream_content.encode("cp1252", errors="replace")
+    stream_bytes = s.encode()
 
     objects: list[bytes] = []
     objects.append(b"1 0 obj\n<< /Type /Catalog /Pages 2 0 R >>\nendobj\n")

doc/MODULES.md

@@ -51,6 +51,7 @@ This file provides a mapping of modules to their primary responsibilities and ke
 ## `/infra` (Blender Integration)
 
 - `blender_mesh_capture.py`:
+    - `PdfProperties`: Dataclass holding PDF line width and line color attributes for a `SlicingObject`.
     - `SlicingObject`: Represents a single mesh as a NumPy triangle array.
     - `capture_mesh_edges()`: Extracts edges from a Blender mesh for path-based workflows. Supports capturing extra per-vertex attributes.
 

doc/NODES.md

@@ -63,6 +63,10 @@ All nodes are found in the **Add (Shift+A)** menu under the **SliceNodes** categ
 - **Rename Mesh**: Overrides the internal metadata name of a `SlicingObject`, `SlicingCollection`, or `SlicingGroup`.
     - **Geometry**: Input geometry data.
     - **Name**: String input socket or property for the new name.
+- **Assign PDF Properties**: Assigns line width (mm) and line color PDF export properties to all `SlicingObject` instances within a `SlicingObject`, `SlicingCollection`, or `SlicingGroup`.
+    - **Geometry**: Input geometry socket.
+    - **Line Width**: Input socket / float property for line width in mm.
+    - **Line Color**: Color property for stroke color.
 - **Transform Geometry**: Moves, rotates, and scales a `SlicingCollection` or `SlicingGroup` relative to the origin.
     - **Mesh**: Input mesh data.
     - **Translation**: 3D vector specifying the translation offset.
@@ -136,7 +140,6 @@ All nodes are found in the **Add (Shift+A)** menu under the **SliceNodes** categ
     - **Arcs**: Checkbox to render arc cutouts and corner fillet radius callouts (R) with ISO 129-1 compliant markings.
     - **Chamfers**: Checkbox to render bevel/chamfer callouts (C) with ISO 129-1 compliant markings.
     - **Step Features**: Checkbox to render interior step/notch feature segment length callouts with ISO 129-1 compliant markings.
-    - **Line Width (mm)**: Stroke width in millimeters for the exported lines. Set to 0 for automatic sizing (5% of minor grid spacing).
     - **Font Size (pt)**: Font size in PostScript points for all text labels and measurement callouts. Set to 0 for automatic sizing (equal to minor grid spacing).
     - **Margin (mm)**: Margin around the geometry grid in mm.
     - **Background**: Color picker for the canvas background.

infra/blender/blender_mesh_capture.py

@@ -86,6 +86,16 @@ def get_evaluated_mesh(obj: Object):
             except Exception:
                 pass
 
+import copy
+from dataclasses import dataclass, field
+
+@dataclass
+class PdfProperties:
+    line_width: float = 0.0
+    line_color: tuple[float, float, float] | None = None
+    show_name: bool = False
+
+
 class SlicingObject():
     name: str
     parent: str
@@ -94,6 +104,7 @@ class SlicingObject():
     object_type: str = "ModelPart"
     modifiers: list[dict] = []
     extruder: int = 1
+    pdf_properties: PdfProperties
 
     def __init__(self, obj: Object | None = None, parent: str = "") -> None:
         if not bpy.context.scene: raise Exception('No scene currently open!')
@@ -103,6 +114,7 @@ class SlicingObject():
         self.attributes = {}
         self.modifiers = []
         self.transforms = []
+        self.pdf_properties = PdfProperties()
 
         assert bpy.context.scene.unit_settings
         scene_scale: float = bpy.context.scene.unit_settings.scale_length
@@ -128,6 +140,7 @@ class SlicingObject():
         merged.parent = objects[0].parent
         merged.object_type = objects[0].object_type
         merged.extruder = objects[0].extruder
+        merged.pdf_properties = copy.deepcopy(objects[0].pdf_properties) if hasattr(objects[0], "pdf_properties") and objects[0].pdf_properties else PdfProperties()
         merged.transforms = []
         for o in objects:
             for t in getattr(o, "transforms", []):

tests/test_arrange.py

@@ -49,8 +49,8 @@ sys.modules['bpy.app'] = MagicMock()
 sys.modules['bpy.app.handlers'] = MagicMock()
 
 # Import the actual classes to test
-from NodeSlicer.core.nodeslicer.nodes.mesh import SLICENODE_ArrangeMesh
-from NodeSlicer.infra.blender.blender_mesh_capture import SlicingGroup, SlicingCollection, SlicingObject
+from NodeSlicer.core.nodeslicer.nodes.mesh import SLICENODE_ArrangeMesh  # pyright: ignore[reportMissingImports]
+from NodeSlicer.infra.blender.blender_mesh_capture import SlicingGroup, SlicingCollection, SlicingObject  # pyright: ignore[reportMissingImports]
 
 class TestArrangeMesh(unittest.TestCase):
     def test_arrange_mesh_simple(self):

tests/test_pdf_exporter.py

@@ -729,6 +729,156 @@ class TestPdfExporter(unittest.TestCase):
         )
         self.assertIsNotNone(h_w)
 
+    def test_pdf_properties_dataclass_on_slicing_object(self):
+        from NodeSlicer.infra.blender.blender_mesh_capture import PdfProperties
+        so = SlicingObject()
+        self.assertIsInstance(so.pdf_properties, PdfProperties)
+        self.assertEqual(so.pdf_properties.line_width, 0.0)
+        self.assertIsNone(so.pdf_properties.line_color)
+        self.assertFalse(so.pdf_properties.show_name)
+
+        so.pdf_properties = PdfProperties(line_width=1.5, line_color=(1.0, 0.0, 0.0), show_name=True)
+        self.assertEqual(so.pdf_properties.line_width, 1.5)
+        self.assertEqual(so.pdf_properties.line_color, (1.0, 0.0, 0.0))
+        self.assertTrue(so.pdf_properties.show_name)
+
+    def test_assign_pdf_properties_node_and_helper(self):
+        from NodeSlicer.infra.blender.blender_mesh_capture import PdfProperties
+        from NodeSlicer.core.nodeslicer.nodes.mesh import _assign_pdf_properties_to_item, SLICENODE_AssignPdfProperties
+
+        so1 = SlicingObject()
+        so1.name = "Obj1"
+        so1.mesh = np.array([[[0, 0, 0], [10, 0, 0], [0, 10, 0], [0, 0, 1]]], dtype=np.float64)
+
+        so2 = SlicingObject()
+        so2.name = "Obj2"
+        so2.mesh = np.array([[[20, 20, 0], [30, 20, 0], [20, 30, 0], [0, 0, 1]]], dtype=np.float64)
+
+        sc1 = SlicingCollection([], "Coll1")
+        sc1.objects = [so1]
+        sc2 = SlicingCollection([], "Coll2")
+        sc2.objects = [so2]
+
+        sg = SlicingGroup([])
+        sg.collections = {"Coll1": sc1, "Coll2": sc2}
+
+        # Apply properties with show_name=True
+        updated_sg = _assign_pdf_properties_to_item(sg, line_width=2.5, line_color=(0.5, 0.5, 1.0), show_name=True)
+        for coll in updated_sg.collections.values():
+            for obj in coll.objects:
+                self.assertEqual(obj.pdf_properties.line_width, 2.5)
+                self.assertEqual(obj.pdf_properties.line_color, (0.5, 0.5, 1.0))
+                self.assertTrue(obj.pdf_properties.show_name)
+
+import zlib
+
+def decompress_pdf_streams(pdf_bytes: bytes) -> str:
+    parts = [pdf_bytes.decode("utf-8", errors="ignore")]
+    idx = 0
+    while True:
+        s_idx = pdf_bytes.find(b"stream\n", idx)
+        offset = 7
+        if s_idx == -1:
+            s_idx = pdf_bytes.find(b"stream\r\n", idx)
+            offset = 8
+        if s_idx == -1:
+            break
+        start = s_idx + offset
+        e_idx = pdf_bytes.find(b"\nendstream", start)
+        if e_idx == -1:
+            e_idx = pdf_bytes.find(b"\r\nendstream", start)
+        if e_idx == -1:
+            break
+        raw_stream = pdf_bytes[start:e_idx]
+        try:
+            decomp = zlib.decompress(raw_stream)
+            parts.append(decomp.decode("utf-8", errors="ignore"))
+        except Exception:
+            parts.append(raw_stream.decode("utf-8", errors="ignore"))
+        idx = e_idx + 9
+    return "\n".join(parts)
+
+
+    def test_export_pdf_with_per_object_pdf_properties(self):
+        from NodeSlicer.infra.blender.blender_mesh_capture import PdfProperties
+        import tempfile
+
+        so1 = SlicingObject()
+        so1.name = "RedBox"
+        so1.mesh = np.array([[[0.0, 0.0, 0.0], [10.0, 0.0, 0.0], [0.0, 10.0, 0.0], [0.0, 0.0, 1.0]]], dtype=np.float64)
+        so1.pdf_properties = PdfProperties(line_width=2.0, line_color=(1.0, 0.0, 0.0), show_name=True)
+
+        so2 = SlicingObject()
+        so2.name = "GreenBox"
+        so2.mesh = np.array([[[20.0, 20.0, 0.0], [30.0, 20.0, 0.0], [20.0, 30.0, 0.0], [0.0, 0.0, 1.0]]], dtype=np.float64)
+        so2.pdf_properties = PdfProperties(line_width=0.5, line_color=(0.0, 1.0, 0.0), show_name=False)
+
+        sc1 = SlicingCollection([], "Coll1")
+        sc1.objects = [so1]
+        sc2 = SlicingCollection([], "Coll2")
+        sc2.objects = [so2]
+
+        sg = SlicingGroup([])
+        sg.collections = {"Coll1": sc1, "Coll2": sc2}
+
+        edges_2d = extract_unique_top_view_edges(sg)
+
+        with tempfile.TemporaryDirectory() as tmpdir:
+            pdf_path = os.path.join(tmpdir, "custom_pdf_props.pdf")
+            export_mesh_to_pdf(
+                edges_2d,
+                pdf_path,
+                draw_wireframe=True,
+                stroke_color=(0.0, 0.0, 0.0),
+                raw_geometry=sg
+            )
+
+            with open(pdf_path, "rb") as f:
+                content = decompress_pdf_streams(f.read())
+
+            # 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)
+            # Check RedBox label is rendered (show_name=True on so1)
+            self.assertIn("(RedBox) Tj", content)
+            self.assertNotIn("(GreenBox) Tj", content)
+
+    def test_export_pdf_fallback_color_and_default_line_width(self):
+        from NodeSlicer.infra.blender.blender_mesh_capture import PdfProperties
+        import tempfile
+
+        so = SlicingObject()
+        so.name = "DefaultPropsBox"
+        so.mesh = np.array([[[0.0, 0.0, 0.0], [10.0, 0.0, 0.0], [0.0, 10.0, 0.0], [0.0, 0.0, 1.0]]], dtype=np.float64)
+        # Default pdf_properties (line_width=0.0, line_color=None, show_name=False)
+        so.pdf_properties = PdfProperties()
+
+        edges_2d = extract_unique_top_view_edges(so)
+
+        with tempfile.TemporaryDirectory() as tmpdir:
+            pdf_path = os.path.join(tmpdir, "fallback_pdf_props.pdf")
+            export_mesh_to_pdf(
+                edges_2d,
+                pdf_path,
+                draw_wireframe=True,
+                stroke_color=(0.2, 0.4, 0.6),
+                raw_geometry=so
+            )
+
+            with open(pdf_path, "rb") as f:
+                content = decompress_pdf_streams(f.read())
+
+            # Wireframe color (0.200 0.400 0.600 RG) should be used
+            self.assertIn("0.200 0.400 0.600 RG", content)
+
+    def test_mesh_to_pdf_node_removed_line_width_and_show_name(self):
+        from NodeSlicer.core.nodeslicer.nodes.output import SLICENODE_MeshToPdf
+        node = SLICENODE_MeshToPdf()
+        self.assertFalse(hasattr(node, "line_width"))
+        self.assertFalse(hasattr(node, "show_name"))
+
 
 if __name__ == '__main__':
     unittest.main()