initial changes without tests and .get_homogenous(?!) methods

weldx/transformations/cs_manager.py

@@ -17,10 +17,11 @@
 from weldx.exceptions import WeldxDeprecationWarning, WeldxException
 from weldx.geometry import SpatialData
 from weldx.time import Time, types_time_like, types_timestamp_like
+from weldx.types import QuantityLike
 from weldx.util import check_matplotlib_available, dataclass_nested_eq
 
 from .local_cs import LocalCoordinateSystem
-from .types import types_coordinates, types_orientation
+from .types import types_coordinates, types_homogeneous, types_orientation
 
 # only import heavy-weight packages on type checking
 if TYPE_CHECKING:  # pragma: no cover
@@ -830,6 +831,51 @@ def create_cs_from_axis_vectors(
             coordinate_system_name, reference_system_name, lcs, lcs_child_in_parent
         )
 
+    def create_cs_from_homogenous_transformation(
+        self,
+        coordinate_system_name: str,
+        reference_system_name: str,
+        transformation_matrix: types_homogeneous,
+        translation_unit: QuantityLike,
+        time: types_time_like = None,
+        time_ref: types_timestamp_like = None,
+        lcs_child_in_parent: bool = True,
+    ):
+        """Create a coordinate system from a homogeneous transformation matrix and add
+        it to the coordinate system manager.
+
+        This function uses the `LocalCoordinateSystem.from_homogeneous_transformation`
+        method of the `LocalCoordinateSystem` class.
+
+        Parameters
+        ----------
+        coordinate_system_name :
+            Name of the new coordinate system.
+        reference_system_name :
+            Name of the parent system. This must have been already added.
+        transformation_matrix :
+            Describes the homogeneous transformation matrix that includes the rotation
+            and the translation (coordinates).
+        translation_unit :
+            Unit describing the value of the translation. Necessary, because the
+            homogeneous transformation matrix is unitless.
+        time :
+            Time data for time dependent coordinate systems.
+        time_ref :
+            Reference time for time dependent coordinate systems
+        lcs_child_in_parent :
+            If set to `True`, the passed `LocalCoordinateSystem` instance describes
+            the new system orientation towards is parent. If `False`, it describes
+            how the parent system is positioned in its new child system.
+
+        """
+        lcs = LocalCoordinateSystem.from_homogenous_transformation(
+            transformation_matrix, translation_unit, time, time_ref
+        )
+        self.add_cs(
+            coordinate_system_name, reference_system_name, lcs, lcs_child_in_parent
+        )
+
     def delete_cs(self, coordinate_system_name: str, delete_children: bool = False):
         """Delete a coordinate system from the coordinate system manager.
 

weldx/transformations/local_cs.py

@@ -18,8 +18,13 @@
 from weldx.core import TimeSeries
 from weldx.exceptions import WeldxException
 from weldx.time import Time, TimeDependent, types_time_like, types_timestamp_like
-from weldx.transformations.types import types_coordinates, types_orientation
+from weldx.transformations.types import (
+    types_coordinates,
+    types_homogeneous,
+    types_orientation,
+)
 from weldx.transformations.util import normalize
+from weldx.types import QuantityLike
 
 __all__ = ("LocalCoordinateSystem",)
 
@@ -540,6 +545,39 @@ def from_axis_vectors(
         t_axes = (1, 0) if mat.ndim == 2 else (1, 2, 0)
         return cls(mat.transpose(t_axes), coordinates, time, time_ref)
 
+    @classmethod
+    def from_homogeneous_transformation(
+        cls,
+        transformation_matrix: types_homogeneous,
+        translation_unit: QuantityLike,
+        time: types_time_like = None,
+        time_ref: types_timestamp_like = None,
+    ) -> LocalCoordinateSystem:
+        """Construct a local coordinate system from a homogeneous transformation matrix.
+
+        Parameters
+        ----------
+        transformation_matrix :
+            Describes the homogeneous transformation matrix that includes the rotation
+            and the translation (coordinates).
+        translation_unit :
+            Unit describing the value of the translation. Necessary, because the
+            homogeneous transformation matrix is unitless.
+        time :
+            Time data for time dependent coordinate systems (Default value = None)
+        time_ref :
+            Optional reference timestamp if ``time`` is a time delta.
+
+        Returns
+        -------
+        LocalCoordinateSystem
+            Local coordinate system
+
+        """
+        orientation = transformation_matrix[:, :3, :3]
+        coordinates = Q_(transformation_matrix[:, :3, 3], translation_unit)
+        return cls(orientation, coordinates=coordinates, time=time, time_ref=time_ref)
+
     @property
     def orientation(self) -> xr.DataArray:
         """Get the coordinate systems orientation matrix.

weldx/transformations/types.py

@@ -9,9 +9,11 @@
 
 types_coordinates = Union[xr.DataArray, npt.ArrayLike, pint.Quantity]
 types_orientation = Union[xr.DataArray, npt.ArrayLike, Rotation]
+types_homogeneous = Union[xr.DataArray, npt.ArrayLike]
 
 
 __all__ = [
     "types_coordinates",
     "types_orientation",
+    "types_homogeneous",
 ]