Implement repository improvements

.github/workflows/tests.yaml

@@ -17,6 +17,6 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
-          pip install -e . -r requirements-dev.txt
+          pip install -e .[full] -r requirements-dev.txt
       - name: Run tests
         run: pytest -q

README.md

@@ -1,6 +1,7 @@
 # LayerForge
 
 [![Build Documentation using MkDocs](https://github.com/ravenoak/layerforge/actions/workflows/docs.yaml/badge.svg)](https://github.com/ravenoak/layerforge/actions/workflows/docs.yaml)
+[![Run Tests](https://github.com/ravenoak/layerforge/actions/workflows/tests.yaml/badge.svg)](https://github.com/ravenoak/layerforge/actions/workflows/tests.yaml)
 
 ## Description
 

docs/development.md

@@ -14,7 +14,7 @@
     - Slice the model into layers of a specified thickness.
 
 4. **Reference Marks**:
-    - Reference marks should be placed at the centroid of each slice, where appropriate.
+    - Reference marks are placed using a stability metric that chooses points far from one another and from the contours.
     - Reference marks should be inherited from adjacent slices where possible, including the shape of the mark.
     - New reference marks should be a different shape when added to a slice where they are not inherited.
     - New reference marks must be introduced to a layer that does have a reference mark inherited from an adjacent slice, to ensure there is continuity in the reassembly process.

layerforge/cli.py

@@ -159,6 +159,7 @@ def cli(
 
     This function wraps all the logic for processing an STL file and
     generating SVG slices while accepting commandline arguments.
+    See ``README.md`` for example usage.
 
     Parameters
     ----------

layerforge/models/loading/__init__.py

@@ -1,6 +1,6 @@
-__all__ = ["LoaderFactory", "Mesh", "TrimeshLoader"]
+__all__ = ["LoaderFactory", "Mesh", "TrimeshMesh", "TrimeshLoader"]
 
-from .mesh import Mesh
+from .mesh import Mesh, TrimeshMesh
 from .implementations.trimesh_loader import TrimeshLoader
 from .base import MeshLoader
 

layerforge/models/loading/implementations/trimesh_loader.py

@@ -5,7 +5,7 @@
 trimesh = require_module("trimesh", "TrimeshLoader")
 
 from layerforge.models.loading.base import MeshLoader
-from layerforge.models.loading.mesh import Mesh
+from layerforge.models.loading.mesh import TrimeshMesh, Mesh
 
 
 class TrimeshLoader(MeshLoader):
@@ -30,4 +30,4 @@ def load_mesh(self, model_file: str) -> Mesh:
             raise ValueError(
                 f"File '{model_file}' contains {len(mesh)} geometries; only a single mesh is supported."
             )
-        return Mesh(mesh)
+        return TrimeshMesh(mesh)

layerforge/models/loading/mesh.py

@@ -1,7 +1,76 @@
+"""Mesh abstractions used by the loaders and slicing logic."""
+
+from __future__ import annotations
+
+from abc import ABC, abstractmethod
 from dataclasses import dataclass
 from typing import Any, Sequence
 
 
+class Mesh(ABC):
+    """Interface describing the operations required by :class:`Model`."""
+
+    @abstractmethod
+    def copy(self) -> "Mesh":
+        """Return a copy of the mesh."""
+
+    @abstractmethod
+    def apply_scale(self, scale: float) -> None:
+        """Scale the mesh in-place."""
+
+    @abstractmethod
+    def apply_translation(self, translation: Sequence[float]) -> None:
+        """Translate the mesh in-place."""
+
+    @property
+    @abstractmethod
+    def bounds(self) -> Any:
+        """Return the bounding box of the mesh."""
+
+    @property
+    @abstractmethod
+    def extents(self) -> Any:
+        """Return the extents of the mesh."""
+
+    @abstractmethod
+    def section(
+        self, plane_origin: Sequence[float], plane_normal: Sequence[float]
+    ) -> Any:
+        """Return a section of the mesh at the given plane."""
+
+
+@dataclass
+class TrimeshMesh(Mesh):
+    """Wrapper around a :class:`trimesh.Trimesh` object."""
+
+    geometry: Any
+
+    def copy(self) -> "TrimeshMesh":
+        return TrimeshMesh(self.geometry.copy())
+
+    def apply_scale(self, scale: float) -> None:
+        self.geometry.apply_scale(scale)
+
+    def apply_translation(self, translation: Sequence[float]) -> None:
+        self.geometry.apply_translation(translation)
+
+    @property
+    def bounds(self) -> Any:
+        return self.geometry.bounds
+
+    @property
+    def extents(self) -> Any:
+        return self.geometry.extents
+
+    def section(
+        self, plane_origin: Sequence[float], plane_normal: Sequence[float]
+    ) -> Any:
+        return self.geometry.section(
+            plane_origin=plane_origin, plane_normal=plane_normal
+        )
+
+
+
 @dataclass
 class Mesh:
     """Lightweight wrapper around an underlying mesh implementation."""

layerforge/models/reference_marks/reference_mark_calculator.py

@@ -27,7 +27,9 @@ class ReferenceMarkCalculator:
     The calculator evaluates candidate points inside each polygon and selects
     those that maximize a simple geometric stability metric. The metric used is
     inspired by GDOP (Geometric Dilution of Precision) and rewards points that
-    are well spread out.
+    are well spread out.  Marks therefore rarely lie exactly at the centroid of
+    the contour; rather, candidates are sampled and the most stable arrangement
+    is chosen.
     """
 
     @staticmethod

tests/test_cli.py

@@ -130,3 +130,22 @@ def test_cli_invalid_layer_height(monkeypatch):
     )
     assert result.exit_code != 0
     assert "Invalid value for --layer-height" in result.output
+
+
+def test_cli_missing_stl_file_error(tmp_path):
+    """Missing STL path should result in a non-zero exit code."""
+    runner = CliRunner()
+    out_dir = tmp_path / "out"
+    result = runner.invoke(
+        cli,
+        [
+            "--stl-file",
+            str(tmp_path / "missing.stl"),
+            "--layer-height",
+            "1.0",
+            "--output-folder",
+            str(out_dir),
+        ],
+    )
+    assert result.exit_code != 0
+    assert result.exception is not None

tests/test_model_factory.py

@@ -1,11 +1,10 @@
 import pytest
 
 pytest.importorskip("trimesh")
-
 import trimesh
 from layerforge.models.model_factory import ModelFactory
 from layerforge.models.loading.base import MeshLoader
-from layerforge.models.loading.mesh import Mesh
+from layerforge.models.loading.mesh import TrimeshMesh as Mesh
 
 
 class DummyLoader(MeshLoader):