def main(): ''' uncomment functions to test them you can uncomment the display functions the respective functions to view the geometries ''' # BRepFeat_SplitShape_example() # works to split faces - how to get a Geom_Surface? # BRepAlgoAPI_Cut_example() # no split results GEOMAlgo_Splitter_example() # segmentation fault example def BRepFeat_SplitShape_example(): """ example using BRepFeat_SplitShape_example""" # create geometry handle_splitterCurve, aProjCurveShape, aSectionCurveShape, handle_sweptSurface_trimmed_bsplinesurf, handle_sweptSurface_cutter_trimmed_bsplinesurf = geometry() from OCC.BRepFeat import BRepFeat_SplitShape from OCC.BRep import BRep_Tool from OCC.Utils.Topology import Topo from OCC.TopTools import TopTools_ListOfShape from OCC.TopoDS import TopoDS # make a face and an edge for the splitter from the geometric entities aFace_orig = makeFace(handle_sweptSurface_trimmed_bsplinesurf) topologyOfCurve = Topo(aSectionCurveShape) aEdge_cutter = topologyOfCurve.edges().next() # instantiate the splitter and add the cutter splitter = BRepFeat_SplitShape(aFace_orig) splitter.Add(aEdge_cutter,aFace_orig) # build result splitter.Build() # iterator for the result objects iter = TopTools_ListOfShape() iter.Set(splitter.Modified(aFace_orig)) # # get the results shape = iter.First() shape_other_edge = iter.Last() ### DISPLAY for debug # shapes_to_display = [shape] # shapes_to_display = [shape_other_edge] # shapes_to_display = [shape_other_edge,shape] # display_shape(shapes_to_display) # ############################# # Now try to convert result to a surface # ############################# # convert a shape to a face face_shape_other_edge = TopoDS.face(shape_other_edge) # this face is splitted # generate a surface from the shape surf = BRep_Tool.Surface(face_shape_other_edge) # this surface is like the original surface ### DISPLAY for debug shapes_to_display = [surf] display_shape(shapes_to_display) def BRepAlgoAPI_Cut_example(): """ example using BRepAlgoAPI_Cut""" # create geometry handle_splitterCurve, aProjCurveShape, aSectionCurveShape, handle_sweptSurface_trimmed_bsplinesurf, handle_sweptSurface_cutter_trimmed_bsplinesurf = geometry() from OCC.BRepAlgoAPI import BRepAlgoAPI_Cut # make a face and cutter Face for the cutter from the geometric entities aFace_orig = makeFace(handle_sweptSurface_trimmed_bsplinesurf) aFace_cutter = makeFace(handle_sweptSurface_cutter_trimmed_bsplinesurf) # instantiate the cutter cutter = BRepAlgoAPI_Cut(aFace_orig,aFace_cutter) # ##### operations: # BOP_SECTION # BOP_COMMON # BOP_FUSE # BOP_CUT # BOP_CUT21 # set the cut operation cutter.SetOperation(4) print "Operation",cutter.Operation() # generate results cutter.Build() # get the result ResultShape = cutter.Shape() ### DISPLAY for debug shapes_to_display = [ResultShape,aFace_orig] display_shape(shapes_to_display) def GEOMAlgo_Splitter_example(): """ example using GEOMAlgo_Splitter segmetation fault at Perform() versions: OCE-12 pythonOCC master - also tried with 0.6-dev and 0.6-beta """ # create geometry handle_splitterCurve, aProjCurveShape, aSectionCurveShape,handle_sweptSurface_trimmed_bsplinesurf,handle_sweptSurface_cutter_trimmed_bsplinesurf = geometry() from OCC.GEOMAlgo import GEOMAlgo_Splitter from OCC.Utils.Topology import Topo # make a face and cutter Face for the Splitter from the geometric entities aFace_orig = makeFace(handle_sweptSurface_trimmed_bsplinesurf) aFace_cutter = makeFace(handle_sweptSurface_cutter_trimmed_bsplinesurf) # # alternative cutter topologyOfCurve = Topo(aSectionCurveShape) aEdge_cutter = topologyOfCurve.edges().next() ### DISPLAY for debug # shapes_to_display = [aFace_orig,aFace_cutter] # display_shape(shapes_to_display) # instantiate the Splitter splitter_Algo = GEOMAlgo_Splitter() # add the shape to be split splitter_Algo.AddShape(aFace_orig) # add the shape that works as a cutter splitter_Algo.AddTool(aFace_cutter) # splitter_Algo.AddTool(aEdge_cutter) # alternative cutter # run splitter splitter_Algo.Perform() # segmentation fault here # resulting shape result_shape = splitter_Algo.Shape() # ################################# # geometry function # ################################# def geometry(): """ Create an arbitrary shell and a projected curve on this shell""" from OCC.gp import gp_Ax2 from OCC.gp import gp_Circ from OCC.gp import gp_Dir from OCC.gp import gp_Pnt from OCC.gp import gp_Vec from OCC.GC import GC_MakeArcOfCircle from OCC.Geom import Geom_SurfaceOfLinearExtrusion from OCC.Geom import Geom_RectangularTrimmedSurface from OCC.GeomConvert import GeomConvert_SurfaceToBSplineSurface from OCC.GeomAPI import GeomAPI_PointsToBSpline from OCC.Utils.Common import point_list_to_TColgp_Array1OfPnt from OCC.BRepAlgo import BRepAlgo_NormalProjection from OCC.BRepAlgoAPI import BRepAlgoAPI_Section # # radius = 300. length = 600. pi = 3.14159265359 angle_of_segment = pi/2. # ###################### # Surface # ###################### aAx2 = gp_Ax2(gp_Pnt(0,0,0), gp_Dir(0,1,0)) # in y direction aCircle = gp_Circ(aAx2,radius) # Trim arc to 90 degree arc aCurve = GC_MakeArcOfCircle(aCircle,0,angle_of_segment,1).Operator() handle_sweptSurface = Geom_SurfaceOfLinearExtrusion(aCurve, gp_Dir(gp_Vec(gp_Pnt(0,0,0),gp_Pnt(0,1,0)))).GetHandle() # in y direction handle_sweptSurface_trimmed = Geom_RectangularTrimmedSurface(handle_sweptSurface,0,angle_of_segment,0,length/2.).GetHandle() # handle_sweptSurface_trimmed_bsplinesurf = GeomConvert_SurfaceToBSplineSurface(handle_sweptSurface_trimmed) # ###################### # Curve # ###################### P1 = gp_Pnt(240,400,100) P2 = gp_Pnt(150,-100,100) handle_splitterCurve = GeomAPI_PointsToBSpline(point_list_to_TColgp_Array1OfPnt([P1,P2])).Curve() # ###################### # extruded Surface from curve # ###################### handle_sweptSurface_cutter = Geom_SurfaceOfLinearExtrusion(handle_splitterCurve, gp_Dir(gp_Vec(gp_Pnt(0,0,0),gp_Pnt(0,0,1)))).GetHandle() # in z direction handle_sweptSurface_cutter_trimmed = Geom_RectangularTrimmedSurface(handle_sweptSurface_cutter,0,500,0,1).GetHandle() # handle_sweptSurface_cutter_trimmed_bsplinesurf = GeomConvert_SurfaceToBSplineSurface(handle_sweptSurface_cutter_trimmed) # ###################### # Curve projection on surface or curve intersection of the two surfaces # ###################### # normal PROJECTION is not equal to intersection depending on extrusion direction! aFace = makeFace(handle_sweptSurface_trimmed_bsplinesurf) aEdge = makeEdge(handle_splitterCurve) # projection = BRepAlgo_NormalProjection(aFace) projection.Add(aEdge) projection.Build() if projection.IsDone(): aProjCurveShape = projection.Projection() # INTERSECTION aFace_orig = makeFace(handle_sweptSurface_trimmed_bsplinesurf) aFace_cutter = makeFace(handle_sweptSurface_cutter_trimmed_bsplinesurf) aSectionGenerator = BRepAlgoAPI_Section(aFace_orig,aFace_cutter,False) aSectionGenerator.ComputePCurveOn1(True) aSectionGenerator.Approximation(True) aSectionGenerator.Build() if aSectionGenerator.IsDone(): aSectionCurveShape = aSectionGenerator.Shape() # ############### # Display geometry for debug # ############### # shapes_to_display = [aProjCurveShape,handle_sweptSurface_trimmed_bsplinesurf,aSectionCurveShape,handle_sweptSurface_cutter_trimmed_bsplinesurf] # shapes_to_display = [aProjCurveShape,handle_sweptSurface_trimmed_bsplinesurf,handle_splitterCurve,handle_sweptSurface_cutter_trimmed_bsplinesurf] # display_shape(shapes_to_display) return handle_splitterCurve, aProjCurveShape, aSectionCurveShape,handle_sweptSurface_trimmed_bsplinesurf,handle_sweptSurface_cutter_trimmed_bsplinesurf # ################################# # display functions # ################################# def display_shape(shapes=[]): """displays geometry or shapes in list""" from OCC.Display.SimpleGui import init_display backend_str = "wx" backend_str = "pyqt4" #much preferred backend_str = "qt" display, start_display, add_menu, add_function_to_menu = init_display(backend_str=backend_str) # convert entities to displayable shapes shapes_to_display = [] for entity in shapes: # print entity shapes_to_display.append(convertGeomToShape(entity)) display.DisplayShape(shapes_to_display) display.FitAll() start_display() def convertGeomToShape(geom): """ converts geometric entities to shapes""" from OCC.TopoDS import TopoDS_Shape from OCC.Geom import Handle_Geom_BSplineSurface from OCC.Geom import Handle_Geom_BSplineCurve from OCC.Geom import Handle_Geom_Surface # ################# # Shape types # ################# if isinstance(geom,TopoDS_Shape): return geom # ################# # Surface types # ################# elif isinstance(geom,Handle_Geom_BSplineSurface): return makeFace(geom) elif isinstance(geom,Handle_Geom_Surface): return makeFace(geom) # ################# # Curve types # ################# elif isinstance(geom,Handle_Geom_BSplineCurve): return makeEdge(geom) else: raise Exception("-ERROR: instance not known. Can not convert to Shape. Instance of type %s" % (type(geom))) def makeFace(surface): """ Create a OCC face from a geometric surface. shape :Parameters: surface : OCC surface shape :Returns: face.Shape() : OCC face shape """ from OCC.BRepBuilderAPI import BRepBuilderAPI_MakeFace tol_degen = 1e-6 face = BRepBuilderAPI_MakeFace(surface, tol_degen) face.Build() return face.Face() def makeEdge(curve): """ Create a OCC edge from a geometric curve shape. :Parameters: curve : OCC curve shape :Returns: spline.Shape() : OCC spline shape """ from OCC.BRepBuilderAPI import BRepBuilderAPI_MakeEdge edge = BRepBuilderAPI_MakeEdge(curve) edge.Build() return edge.Edge() if __name__=='__main__': # main()