Initial implementation of "Intersect NURBS curves" node.

92ced428 · Ilya Portnov · e27a635c · 92ced428 · 92ced428 · 92ced428
--- a/index.md
+++ b/index.md
@@ -102,6 +102,7 @@
    SvReparametrizeCurveNode
    SvExSurfaceBoundaryNode
    ---
+    SvIntersectNurbsCurvesNode
    SvExNearestPointOnCurveNode
    SvExOrthoProjectCurveNode
    SvExCurveEndpointsNode

--- a/nodes/curve/intersect_curves.py
+++ b/nodes/curve/intersect_curves.py
+# This file is part of project Sverchok. It's copyrighted by the contributors
+# recorded in the version control history of the file, available from
+# its original location https://github.com/nortikin/sverchok/commit/master
+#
+# SPDX-License-Identifier: GPL3
+# License-Filename: LICENSE
+import numpy as np
+import bpy
+from mathutils import Vector
+from bpy.props import FloatProperty, EnumProperty, BoolProperty, IntProperty
+from sverchok.node_tree import SverchCustomTreeNode
+from sverchok.data_structure import updateNode, zip_long_repeat, ensure_nesting_level, split_by_count
+from sverchok.utils.curve import SvCurve
+from sverchok.utils.curve.nurbs import SvNurbsCurve
+from sverchok.utils.curve.nurbs_algorithms import intersect_nurbs_curves
+from sverchok.utils.curve.freecad import curve_to_freecad, SvSolidEdgeCurve
+from sverchok.dependencies import FreeCAD
+class SvIntersectNurbsCurvesNode(bpy.types.Node, SverchCustomTreeNode):
+    """
+    Triggers: Intersect Curves
+    Tooltip: Find intersection points of two NURBS curves
+    """
+    bl_idname = 'SvIntersectNurbsCurvesNode'
+    bl_label = 'Intersect NURBS Curves'
+    bl_icon = 'OUTLINER_OB_EMPTY'
+    #sv_icon = 'SV_CONCAT_CURVES'
+    def get_implementations(self, context):
+        result = []
+        if FreeCAD is not None:
+            item = ('FREECAD', "FreeCAD", "Implementation from FreeCAD library", 0)
+            result.append(item)
+        item = ('NATIVE', "Sverchok", "Sverchok built-in implementation", 1)
+        result.append(item)
+        return result
+    implementation : EnumProperty(
+            name = "Implementation",
+            items = get_implementations,
+            update = updateNode)
+    match_methods = [
+            ('LONG', "Longest", "", 0),
+            ('CROSS', "Cross", "", 1)
+        ]
+    matching : EnumProperty(
+            name = "Matching",
+            items = match_methods,
+            update = updateNode)
+    single : BoolProperty(
+            name = "Find single intersection",
+            default = True,
+            update = updateNode)
+    precision : FloatProperty(
+            name = "Precision",
+            default = 0.001,
+            precision = 6,
+            min = 0,
+            update = updateNode)
+    methods = [
+            ('Nelder-Mead', "Nelder-Mead", "", 0),
+            ('L-BFGS-B', 'L-BFGS-B', "", 1),
+            ('SLSQP', 'SLSQP', "", 2),
+            ('Powell', 'Powell', "", 3),
+            ('trust-constr', 'Trust-Constr', "", 4)
+        ]
+    method : EnumProperty(
+            name = "Numeric method",
+            items = methods,
+            default = methods[0][0],
+            update = updateNode)
+    split : BoolProperty(
+            name = "Split by row",
+            default = True,
+            update = updateNode)
+    def draw_buttons(self, context, layout):
+        layout.prop(self, 'implementation', text='')
+        layout.prop(self, 'matching')
+        layout.prop(self, 'single')
+        if self.matching == 'CROSS':
+            layout.prop(self, 'split')
+    def draw_buttons_ext(self, context, layout):
+        self.draw_buttons(context, layout)
+        if self.implementation == 'NATIVE':
+            layout.prop(self, 'precision')
+            layout.prop(self, 'method')
+    def sv_init(self, context):
+        self.inputs.new('SvCurveSocket', "Curve1")
+        self.inputs.new('SvCurveSocket', "Curve2")
+        self.outputs.new('SvVerticesSocket', "Intersections")
+    def _filter(self, points):
+        if not points:
+            return points
+        prev = points[0]
+        result = [prev]
+        for p in points[1:]:
+            r = (Vector(p) - Vector(prev)).length
+            if r > 1e-4:
+                result.append(p)
+            prev = p
+        return result
+    def process_native(self, curve1, curve2):
+        res = intersect_nurbs_curves(curve1, curve2,
+                    method = self.method,
+                    numeric_precision = self.precision)
+        points = [r[2].tolist() for r in res]
+        return self._filter(points)
+    def process_freecad(self, sv_curve1, sv_curve2):
+        fc_curve1 = curve_to_freecad(sv_curve1)[0]
+        fc_curve2 = curve_to_freecad(sv_curve2)[0]
+        points = fc_curve1.curve.intersectCC(fc_curve2.curve)
+        points = [(p.X, p.Y, p.Z) for p in points]
+        return self._filter(points)
+    def match(self, curves1, curves2):
+        if self.matching == 'LONG':
+            return zip_long_repeat(curves1, curves2)
+        else:
+            return [(c1, c2) for c2 in curves2 for c1 in curves1]
+    def process(self):
+        if not any(socket.is_linked for socket in self.outputs):
+            return
+        curve1_s = self.inputs['Curve1'].sv_get()
+        curve2_s = self.inputs['Curve2'].sv_get()
+        curve1_s = ensure_nesting_level(curve1_s, 2, data_types=(SvCurve,))
+        curve2_s = ensure_nesting_level(curve2_s, 2, data_types=(SvCurve,))
+        points_out = []
+        for curve1s, curve2s in zip_long_repeat(curve1_s, curve2_s):
+            new_points = []
+            for curve1, curve2 in self.match(curve1s, curve2s):
+                curve1 = SvNurbsCurve.to_nurbs(curve1)
+                if curve1 is None:
+                    raise Exception("Curve1 is not a NURBS")
+                curve2 = SvNurbsCurve.to_nurbs(curve2)
+                if curve2 is None:
+                    raise Exception("Curve2 is not a NURBS")
+                if self.implementation == 'NATIVE':
+                    ps = self.process_native(curve1, curve2)
+                else:
+                    ps = self.process_freecad(curve1, curve2)
+                if self.single:
+                    if len(ps) >= 1:
+                        ps = ps[0]
+                new_points.append(ps)
+            if self.split:
+                n = len(curve1s)
+                new_points = split_by_count(new_points, n)
+            points_out.append(new_points)
+        self.outputs['Intersections'].sv_set(points_out)
+def register():
+    bpy.utils.register_class(SvIntersectNurbsCurvesNode)
+def unregister():
+    bpy.utils.unregister_class(SvIntersectNurbsCurvesNode)
--- a/utils/curve/nurbs_algorithms.py
+++ b/utils/curve/nurbs_algorithms.py
@@ -190,7 +190,7 @@ def intersect_segment_segment_mu(v1, v2, v3, v4):
        return np.array(v)
    return None
-def _intersect_curves_equation(curve1, curve2):
+def _intersect_curves_equation(curve1, curve2, method='SLSQP', precision=0.001):
    t1_min, t1_max = curve1.get_u_bounds()
    t2_min, t2_max = curve2.get_u_bounds()
@@ -231,9 +231,9 @@ def _intersect_curves_equation(curve1, curve2):
    #print(f"Call R: [{t1_min} - {t1_max}] x [{t2_min} - {t2_max}]")
    #res = scipy.optimize.root(constrained_goal, x0, method='hybr', tol=0.001)
-    res = scipy.optimize.minimize(goal, x0, method='SLSQP',
+    res = scipy.optimize.minimize(goal, x0, method=method,
-                bounds = [(t1_min, t1_max), (t2_min, t2_max)])
+                bounds = [(t1_min, t1_max), (t2_min, t2_max)],
-                #tol = 0.0001)
+                tol = 0.5 * precision)
    if res.success:
        t1, t2 = tuple(res.x)
        t1 = np.clip(t1, t1_min, t1_max)
@@ -241,7 +241,7 @@ def _intersect_curves_equation(curve1, curve2):
        pt1 = curve1.evaluate(t1)
        pt2 = curve2.evaluate(t2)
        dist = np.linalg.norm(pt2 - pt1)
-        if dist < 0.001:
+        if dist < precision:
            #print(f"Found: T1 {t1}, T2 {t2}, Pt1 {pt1}, Pt2 {pt2}")
            pt = (pt1 + pt2) * 0.5
            return [(t1, t2, pt)]
@@ -252,7 +252,7 @@ def _intersect_curves_equation(curve1, curve2):
        print(f"numeric method fail: [{t1_min} - {t1_max}] x [{t2_min} - {t2_max}]: {res.message}")
        return []
-def intersect_nurbs_curves(curve1, curve2):
+def intersect_nurbs_curves(curve1, curve2, method='SLSQP', numeric_precision=0.001):
    bbox_tolerance = 1e-4
@@ -271,7 +271,7 @@ def intersect_nurbs_curves(curve1, curve2):
        if bbox1.size() < THRESHOLD and bbox2.size() < THRESHOLD:
        #if _check_is_line(curve1) and _check_is_line(curve2):
-            return _intersect_curves_equation(curve1, curve2)
+            return _intersect_curves_equation(curve1, curve2, method=method, precision=numeric_precision)
        mid1 = (t1_min + t1_max) * 0.5
        mid2 = (t2_min + t2_max) * 0.5