Curve functionalities

CHANGELOG.md

@@ -15,6 +15,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 * Added `compas_occ.brep.BRepLoop`.
 * Added `compas_occ.brep.BRepVertex`.
 
+* Added `compas_occ.geometry.NurbsCurve.segment`.
+* Added `compas_occ.geometry.NurbsCurve.segmented`.
+* Added `compas_occ.geometry.NurbsCurve.closest_point`.
+
 ### Changed
 
 ### Removed

docs/examples/curve_closest_point.py

@@ -0,0 +1,25 @@
+from compas.geometry import Point, Polyline
+from compas_occ.geometry import NurbsCurve
+
+from compas_view2.app import App
+
+points = [Point(0, 0, 0), Point(3, 0, 2), Point(6, 0, -3), Point(8, 0, 0)]
+curve = NurbsCurve.from_interpolation(points)
+
+projection_point = Point(2, -1, 0)
+
+closest_point, t = curve.closest_point(projection_point, parameter=True) 
+
+print(curve.point_at(t) == closest_point)
+
+# ==============================================================================
+# Visualisation
+# ==============================================================================
+
+view = App()
+
+view.add(Polyline(curve.locus()), linewidth=3)
+view.add(projection_point, pointcolor = (0, 0, 1))
+view.add(closest_point, pointcolor = (1, 0, 0))
+
+view.run()

docs/examples/curve_closest_point.rst

@@ -0,0 +1,14 @@
+********************************************************************************
+Curve Closest Point
+********************************************************************************
+
+.. figure:: /_images/example_curve_closest_point.png
+    :figclass: figure
+    :class: figure-img img-fluid
+
+.. literalinclude:: curve_closest_point.py
+    :language: python
+
+.. code-block:: text
+
+    True

docs/examples/curve_segmentation.py

@@ -0,0 +1,34 @@
+from compas.geometry import Point, Polyline
+from compas_occ.geometry import NurbsCurve
+
+from compas_view2.app import App
+
+
+pointsA = [Point(0, 0, 0), Point(3, 6, 0), Point(6, -3, 3), Point(10, 0, 0)]
+curveA = NurbsCurve.from_points(pointsA)
+
+curveA.segment(u=0.2, v=0.5)
+
+print(curveA.domain)
+
+
+pointsB = [Point(0, -1, 0), Point(3, 5, 0), Point(6, -4, 3), Point(10, -1, 0)]
+curveB = NurbsCurve.from_points(pointsB)
+
+segment = curveB.segmented(u=0.2, v=0.5)
+
+print(curveB.domain)
+print(segment.domain)
+
+# ==============================================================================
+# Visualisation
+# ==============================================================================
+
+view = App()
+
+view.add(Polyline(curveA.locus()), linewidth=4, linecolor=(1, 0, 0))
+
+view.add(Polyline(curveB.locus()), linewidth=1, linecolor=(0, 0, 0))
+view.add(Polyline(segment.locus()), linewidth=4, linecolor=(0, 1, 0))
+
+view.run()

docs/examples/curve_segmentation.rst

@@ -0,0 +1,17 @@
+********************************************************************************
+Curve Segmentation
+********************************************************************************
+
+.. figure:: /_images/example_segmentation.png
+    :figclass: figure
+    :class: figure-img img-fluid
+
+.. literalinclude:: curve_segmentation.py
+    :language: python
+
+.. code-block:: text
+
+    (0.2, 0.5)
+
+    (0.0, 1.0)
+    (0.2, 0.5)

src/compas_occ/geometry/curves/nurbs.py

@@ -20,6 +20,7 @@
 from OCC.Core.gp import gp_Trsf
 from OCC.Core.Geom import Geom_BSplineCurve
 from OCC.Core.GeomAPI import GeomAPI_Interpolate
+from OCC.Core.GeomAPI import GeomAPI_ProjectPointOnCurve
 from OCC.Core.GeomAdaptor import GeomAdaptor_Curve
 from OCC.Core.GCPnts import GCPnts_AbscissaPoint_Length
 from OCC.Core.Bnd import Bnd_Box
@@ -601,9 +602,27 @@ def frame_at(self, t):
         """
         pass
 
-    def closest_point(self, point, distance=None):
-        """Compute the closest point on the curve to a given point."""
-        pass
+    def closest_point(self, point: Point, parameter: bool = False) -> Point:
+        """Compute the closest point on the curve to a given point.
+
+        Parameters
+        ----------
+        point : Point
+            The point to project orthogonally to the curve.
+        parameter : bool, optional
+            Return the projected point as well as the curve parameter.
+
+        Returns
+        -------
+        Point or tuple
+            The nearest point on the curve, if ``parameter`` is false.
+            The nearest as (point, parameter) tuple, if ``parameter`` is true.
+        """
+        projector = GeomAPI_ProjectPointOnCurve(point.to_occ(), self.occ_curve)
+        point = Point.from_occ(projector.NearestPoint())
+        if not parameter:
+            return point
+        return point, projector.LowerDistanceParameter()
 
     def divide_by_count(self, count):
         """Divide the curve into a specific number of equal length segments."""
@@ -631,3 +650,46 @@ def obb(self, precision: float = 0.0) -> Box:
     def length(self, precision: float = 1e-3) -> float:
         """Compute the length of the curve."""
         return GCPnts_AbscissaPoint_Length(GeomAdaptor_Curve(self.occ_curve))
+
+    def segment(self, u: float, v: float, precision: float = 1e-3) -> None:
+        """Modifies this curve by segmenting it between the parameters u and v.
+
+        Parameters
+        ----------
+        u: float
+        v: float
+        tol: float, optional
+            default value is 1e-3
+
+        Returns
+        -------
+        None
+
+        """
+        if u > v:
+            u, v = v, u
+        s, e = self.domain
+        if u < s or v > e:
+            raise ValueError('At least one of the given parameters is outside the curve domain.')
+        if u == v:
+            raise ValueError('The given domain is zero length.')
+        self.occ_curve.Segment(u, v, precision)
+
+    def segmented(self, u: float, v: float, precision: float = 1e-3) -> 'NurbsCurve':
+        """Returns a copy of this curve by segmenting it between the parameters u and v.
+
+        Parameters
+        ----------
+        u: float
+        v: float
+        tol: float,optional
+            default value is 1e-3
+
+        Returns
+        -------
+        NurbsCurve
+
+        """
+        copy = self.copy()
+        copy.occ_curve.Segment(u, v, precision)
+        return copy