move rdp to optional dev dep, cgal always available

Author: claude

pyproject.toml

@@ -36,7 +36,6 @@ dependencies = [
     "numpy>=2.0",
     "progressbar2>=4.5",
     "pyclipper>=1.3",
-    "rdp>=0.8",
     "scipy>=1.16",
     "tomli>=2.0; python_version < '3.11'",
 ]
@@ -58,6 +57,7 @@ dev = [
     "pytest>=7.0",
     "pytest-benchmark",
     "pytest-cov",
+    "rdp>=0.8",
     "ruff",
     "twine",
 ]

src/compas_slicer/post_processing/simplify_paths_rdp.py

@@ -3,10 +3,14 @@
 from typing import TYPE_CHECKING
 
 import numpy as np
-import rdp as rdp_py
 from compas.geometry import Point
 from loguru import logger
 
+try:
+    import rdp as rdp_py
+except ImportError:
+    rdp_py = None
+
 if TYPE_CHECKING:
     from compas_slicer.slicers import BaseSlicer
 
@@ -69,6 +73,9 @@ def _simplify_paths_cgal(slicer: BaseSlicer, threshold: float) -> None:
 
 def _simplify_paths_python(slicer: BaseSlicer, threshold: float) -> None:
     """Simplify paths using Python rdp library."""
+    if rdp_py is None:
+        raise ImportError("rdp package required for Python fallback. Install with: pip install rdp")
+
     logger.info("Paths simplification rdp (Python)")
     remaining_pts_num = 0