applications/utilities/mesh/generation/cfMesh/python/Salome/extractFeatureEdges.py

   1 #!python
   2 # =============================================================================
   3 # Salome GEOM script to extract the feature edges from a body and add them
   4 # to the group named 'featureEdges'.
   5 # Tested on Salome 7.4.0 and python 2.7 on 64-bit Windows
   6 #
   7 # Author: Ivor Clifford <ivor.clifford@psi.ch>
   8 #
   9 # =============================================================================
  10
  11 def extractFeatureEdges(body, minFeatureAngle = 5):
  12     '''
  13     Find all feature edges on the supplied body and return them as a list
  14     of edge ids.
  15
  16         body - A Salome solid, compound, shell or face object to find all
  17                 feature edges on.
  18         minFeatureAngle - the angle (in degrees) between adjacent surfaces
  19                 above which the edge will be considered a feature angle.
  20     '''
  21     import salome
  22     salome.salome_init()
  23
  24     import GEOM
  25     from salome.geom import geomBuilder
  26     geompy = geomBuilder.New(salome.myStudy)
  27
  28     # Check the body type
  29     if not (body.GetShapeType() in [GEOM.SHELL, GEOM.SOLID, GEOM.FACE, GEOM.COMPOUND]):
  30        raise RuntimeError('Supplied object is not a solid, shell or face.')
  31
  32     print 'Extracting edges of %s with feature angle > %g.' % (body.GetName(), minFeatureAngle)
  33
  34     # Extract basic info
  35     faces = geompy.SubShapeAll(body, geompy.ShapeType["FACE"])
  36     curves = geompy.SubShapeAll(body, geompy.ShapeType["EDGE"])
  37     points = geompy.SubShapeAll(body, geompy.ShapeType["VERTEX"])
  38
  39     faceIds = geompy.GetSubShapesIDs(body, faces)
  40     curveIds = geompy.GetSubShapesIDs(body, curves)
  41     nodeIds = geompy.GetSubShapesIDs(body, points)
  42
  43     maxFaceId = max(faceIds)
  44     maxCurveId = max(curveIds)
  45     maxNodeId = max(nodeIds)
  46
  47     # Reverse mapping from curve id to local curve arrays
  48     faceMap = [-1 for i in xrange(maxFaceId+1)]
  49     for localId, id in enumerate(faceIds):
  50         faceMap[id] = localId
  51
  52     curveMap = [-1 for i in xrange(maxCurveId+1)]
  53     for localId, id in enumerate(curveIds):
  54         curveMap[id] = localId
  55
  56     nodeMap = [-1 for i in xrange(maxNodeId+1)]
  57     for localId, id in enumerate(nodeIds):
  58         nodeMap[id] = localId
  59
  60
  61     # Get curves on each face
  62     faceCurveIds = [[curveMap[id] for id in geompy.GetSubShapesIDs(
  63             body,
  64             geompy.SubShapeAll(face, geompy.ShapeType["EDGE"])
  65         )] for face in faces]
  66
  67     # Get faces attached to each curve
  68     curveFaceIds = [[] for id in curveIds]
  69
  70     for faceI, ids in enumerate(faceCurveIds):
  71         for id in ids:
  72             curveFaceIds[id].append(faceI)
  73
  74     # Now that we have the connectivity for curves and faces find the
  75     # feature edges
  76     featureEdgeIds = []
  77     for curveId, curve, adjFaceIds in zip(curveIds, curves, curveFaceIds):
  78         if len(adjFaceIds) == 2:
  79             # Curve with 2 adjacent faces - Test feature angle
  80             # Determine break angle at each curve
  81             # If greater than the feature edge angle, add the curve to group featureEdges
  82             face1 = faces[adjFaceIds[0]]
  83             face2 = faces[adjFaceIds[1]]
  84             point = geompy.GetFirstVertex(curve)    # Test at the first vertex
  85             n1 = geompy.GetNormal(face1, point)
  86             n2 = geompy.GetNormal(face2, point)
  87             angle = geompy.GetAngle(n1, n2)
  88             if angle > minFeatureAngle:
  89                 featureEdgeIds.append(curveId)
  90
  91         elif len(adjFaceIds) == 1:
  92             # Curve on standalone face - Add by default
  93             featureEdgeIds.append(curveId)
  94
  95         elif len(adjFaceIds) == 0:
  96             # Standalone curve - Ignore
  97             None
  98
  99         else:
 100             raise RuntimeError('Curve found sharing %d faces. This is unexpected for fully enclosed bodies.' % len(adjFaceIds))
 101
 102     # Done
 103     print "%d feature edges found" % len(featureEdgeIds)
 104
 105     return featureEdgeIds
 106
 107
 108 # If run as a standalone script, use the current Salome GUI selection
 109 # and add the feature edges to group named 'featureEdges'
 110 if __name__ == '__main__':
 111     import salome
 112     salome.salome_init()
 113
 114     import GEOM
 115     from salome.geom import geomBuilder
 116     geompy = geomBuilder.New(salome.myStudy)
 117
 118     # Get current GUI selection
 119     selected = salome.sg.getAllSelected()
 120     if len(selected) != 1:
 121         raise RuntimeError('A single solid, shell or face object must be selected.')
 122
 123     body = salome.myStudy.FindObjectID(selected[0]).GetObject()
 124
 125     # Get feature edges and add to the group 'featureEdges'
 126     featureEdges = geompy.CreateGroup(body, geompy.ShapeType["EDGE"])
 127     geompy.UnionIDs(featureEdges, extractFeatureEdges(body))
 128     geompy.addToStudyInFather(body, featureEdges, 'featureEdges')
 129
 130     if salome.sg.hasDesktop():
 131         salome.sg.updateObjBrowser(1)