disable head model smoothing by default

Author: emiddell

src/cedalion/dot/head_model.py

@@ -97,7 +97,7 @@ def from_segmentation(
         landmarks_ras_file: str | None = None,
         brain_seg_types: list[str] = ["gm", "wm"],
         scalp_seg_types: list[str] = ["scalp"],
-        smoothing: float = 0.5,
+        smoothing: float = 0.,
         brain_face_count: int | None = 180000,
         scalp_face_count: int | None = 60000,
         fill_holes: bool = True,
@@ -220,7 +220,7 @@ def from_surfaces(
         landmarks_ras_file: str | None = None,
         brain_seg_types: list[str] = ["gm", "wm"],
         scalp_seg_types: list[str] = ["scalp"],
-        smoothing: float = 0.5,
+        smoothing: float = 0.0,
         brain_face_count: int | None = 180000,
         scalp_face_count: int | None = 60000,
         fill_holes: bool = False,