Iges handler

.travis.yml

@@ -17,6 +17,7 @@ install:
     - conda create --yes -n test python=$TRAVIS_PYTHON_VERSION
     - source activate test
     - conda install --yes numpy scipy matplotlib pip nose vtk
+    - conda install --yes -c https://conda.anaconda.org/dlr-sc pythonocc-core
     - pip install setuptools
     - pip install enum34
     - pip install numpy-stl

docs/source/code.rst

@@ -14,4 +14,5 @@ Code Documentation
    stlhandler
    vtkhandler
    unvhandler
+   igeshandler
 

docs/source/igeshandler.rst

@@ -0,0 +1,9 @@
+Igeshandler
+=================
+
+.. automodule:: pygem.igeshandler
+
+.. autoclass:: IgesHandler
+    :members:
+    :private-members:
+    :special-members:

pygem/__init__.py

@@ -1,5 +1,5 @@
 
-__all__ = ['affine', 'filehandler', 'freeform', 'openfhandler', 'params', 'stlhandler', 'unvhandler', 'vtkhandler']
+__all__ = ['affine', 'filehandler', 'freeform', 'openfhandler', 'params', 'stlhandler', 'unvhandler', 'vtkhandler', 'igeshandler']
 
 from . import affine
 from . import freeform
@@ -9,3 +9,4 @@
 from . import stlhandler
 from . import unvhandler
 from . import vtkhandler
+from . import igeshandler

pygem/igeshandler.py

@@ -0,0 +1,226 @@
+"""
+Utilities for reading and writing different CAD files.
+"""
+import numpy as np
+import pygem.filehandler as fh
+from OCC.IGESControl import (IGESControl_Reader, IGESControl_Writer)
+from OCC.BRep import BRep_Tool
+from OCC.BRepBuilderAPI import (BRepBuilderAPI_NurbsConvert, BRepBuilderAPI_MakeWire, BRepBuilderAPI_MakeEdge, BRepBuilderAPI_MakeFace)
+from OCC.GeomConvert import geomconvert_SurfaceToBSplineSurface
+import OCC.TopoDS
+from OCC.TopAbs import (TopAbs_FACE, TopAbs_EDGE)
+from OCC.TopExp import TopExp_Explorer
+from OCC.Geom import Geom_BSplineSurface
+from OCC.gp import (gp_Pnt, gp_XYZ)
+from OCC.Display.SimpleGui import init_display
+from OCC.ShapeFix import ShapeFix_ShapeTolerance
+
+
+class IgesHandler(fh.FileHandler):
+	"""
+	Iges file handler class
+
+	:cvar string infile: name of the input file to be processed.
+	:cvar string outfile: name of the output file where to write in.
+	:cvar string extension: extension of the input/output files. It is equal to '.iges'.
+	:cvar list control_point_position: index of the first NURBS control point (or pole) of each face of the iges file.
+	"""
+	def __init__(self):
+		super(IgesHandler, self).__init__()
+		self.extension = '.iges'	# TODO: also igs could be accepted
+		self._control_point_position = None
+
+
+	def parse(self, filename):
+		"""
+		Method to parse the file `filename`. It returns a matrix with all the coordinates.
+
+		:return: mesh_points: it is a `n_points`-by-3 matrix containing the coordinates of
+			the points of the mesh
+		:rtype: numpy.ndarray
+
+		.. todo::
+
+			- specify when it works
+		"""
+		self._check_filename_type(filename)
+		self._check_extension(filename)
+
+		self.infile = filename
+
+		## read in the IGES file
+		reader = IGESControl_Reader()
+		reader.ReadFile(self.infile)
+		reader.TransferRoots()
+		shape = reader.Shape()
+
+		## cycle on the faces to get the control points
+		# init some quantities
+		n_faces = 0
+		control_point_position = [0]
+		faces_explorer = TopExp_Explorer(shape, TopAbs_FACE)
+		mesh_points = np.zeros(shape=(0,3))
+
+		while faces_explorer.More():
+
+			# performing some conversions to get the right format (BSplineSurface)
+			iges_face = OCC.TopoDS.topods_Face(faces_explorer.Current())
+			iges_nurbs_converter = BRepBuilderAPI_NurbsConvert(iges_face)
+			iges_nurbs_converter.Perform(iges_face)
+			nurbs_face = iges_nurbs_converter.Shape()
+			brep_face = BRep_Tool.Surface(OCC.TopoDS.topods_Face(nurbs_face))
+			bspline_face = geomconvert_SurfaceToBSplineSurface(brep_face)
+
+			# openCascade object
+			occ_face = bspline_face.GetObject()
+
+			# extract the Control Points of each face
+			n_poles_u = occ_face.NbUPoles()
+			n_poles_v = occ_face.NbVPoles()
+			control_polygon_coordinates = np.zeros(shape=(n_poles_u*n_poles_v,3))
+
+			# cycle over the poles to get their coordinates
+			i = 0
+			for pole_u_direction in xrange(n_poles_u):
+				for pole_v_direction in xrange(n_poles_v):
+					control_point_coordinates = occ_face.Pole(pole_u_direction+1,pole_v_direction+1)
+					weight = occ_face.Weight(pole_u_direction+1,pole_v_direction+1)
+					control_polygon_coordinates[i,:] = [control_point_coordinates.X(), control_point_coordinates.Y(), control_point_coordinates.Z()]
+					i += 1	
+
+			# pushing the control points coordinates to the mesh_points array (used for FFD)
+			mesh_points = np.append(mesh_points, control_polygon_coordinates, axis=0)
+			control_point_position.append(control_point_position[-1] + n_poles_u*n_poles_v)
+
+			n_faces += 1
+			faces_explorer.Next()
+
+		print control_point_position
+
+		self._control_point_position = control_point_position
+
+		return mesh_points
+
+
+	def write(self, mesh_points, filename):
+		"""
+		Writes a iges file, called filename, copying all the structures from self.filename but
+		the coordinates. mesh_points is a matrix that contains the new coordinates to
+		write in the iges file.
+
+		:param numpy.ndarray mesh_points: it is a `n_points`-by-3 matrix containing
+			the coordinates of the points of the mesh
+		:param string filename: name of the output file.
+		"""
+		self._check_filename_type(filename)
+		self._check_extension(filename)
+		self._check_infile_instantiation(self.infile)
+
+		self.outfile = filename	
+
+		## init the ouput file writer
+		writer = IGESControl_Writer()
+
+		## read in the IGES file
+		reader = IGESControl_Reader()
+		reader.ReadFile(self.infile)
+		reader.TransferRoots()
+		shape_read = reader.Shape()
+
+		## cycle on the faces to update the control points position
+		# init some quantities
+		faces_explorer = TopExp_Explorer(shape_read, TopAbs_FACE)
+		n_faces = 0
+		control_point_position = self._control_point_position
+
+		while faces_explorer.More():
+
+			# similar to the parser method
+			iges_face = OCC.TopoDS.topods_Face(faces_explorer.Current())
+			iges_nurbs_converter = BRepBuilderAPI_NurbsConvert(iges_face)
+			iges_nurbs_converter.Perform(iges_face)
+			nurbs_face = iges_nurbs_converter.Shape()
+			face_aux = OCC.TopoDS.topods_Face(nurbs_face)
+			brep_face = BRep_Tool.Surface(OCC.TopoDS.topods_Face(nurbs_face))
+			bspline_face = geomconvert_SurfaceToBSplineSurface(brep_face)
+			occ_face = bspline_face.GetObject()
+
+			n_poles_u = occ_face.NbUPoles()
+			n_poles_v = occ_face.NbVPoles()
+
+			i = 0
+			for pole_u_direction in xrange(n_poles_u):
+				for pole_v_direction in xrange(n_poles_v):
+					control_point_coordinates = mesh_points[i+control_point_position[n_faces],:]
+					point_xyz = gp_XYZ(control_point_coordinates[0], control_point_coordinates[1], control_point_coordinates[2])
+					gp_point = gp_Pnt(point_xyz)
+					occ_face.SetPole(pole_u_direction+1,pole_v_direction+1,gp_point)
+					i += 1
+
+			## construct the deformed wire for the trimmed surfaces
+			wireMaker = BRepBuilderAPI_MakeWire()
+			tol = ShapeFix_ShapeTolerance()
+			brep = BRepBuilderAPI_MakeFace(occ_face.GetHandle(), 1e-4).Face()
+			brep_face = BRep_Tool.Surface(brep)
+
+			# cycle on the edges
+			edge_explorer = TopExp_Explorer(nurbs_face, TopAbs_EDGE)
+			while edge_explorer.More():
+				edge = OCC.TopoDS.topods_Edge(edge_explorer.Current())
+				# edge in the (u,v) coordinates
+				edge_uv_coordinates = OCC.BRep.BRep_Tool.CurveOnSurface(edge, face_aux)
+				# evaluating the new edge: same (u,v) coordinates, but different (x,y,x) ones
+				edge_phis_coordinates_aux = BRepBuilderAPI_MakeEdge(edge_uv_coordinates[0], brep_face)
+				edge_phis_coordinates = edge_phis_coordinates_aux.Edge()
+				tol.SetTolerance(edge_phis_coordinates, 1e-4)
+				wireMaker.Add(edge_phis_coordinates)
+				edge_explorer.Next()
+
+			#grouping the edges in a wire
+			wire = wireMaker.Wire()
+
+			## trimming the surfaces
+			brep_surf = BRepBuilderAPI_MakeFace(occ_face.GetHandle(), wire).Face()
+			writer.AddShape(brep_surf)
+
+			#print writer
+
+			n_faces += 1
+			faces_explorer.Next()	
+
+		## write out the iges file
+		writer.Write(self.outfile)
+
+
+	def plot(self, plot_file=None, save_fig=False):
+		"""
+		Method to plot an iges file. If `plot_file` is not given it plots `self.infile`.
+
+		:param string plot_file: the iges filename you want to plot.
+		:param bool save_fig: a flag to save the figure in png or not. If True the
+			plot is not shown.
+
+		.. warning::
+			It does not work well up to now
+		"""
+		if plot_file is None:
+			plot_file = self.infile
+		else:
+			self._check_filename_type(plot_file)
+
+		## read in the IGES file
+		reader = IGESControl_Reader()
+		reader.ReadFile(plot_file)
+		reader.TransferRoots()
+		shape = reader.Shape()
+
+		display, start_display, add_menu, add_function_to_menu = init_display()
+		display.FitAll()
+		display.DisplayShape(shape, update=True)
+
+		# Show the plot to the screen
+		if not save_fig:
+			start_display()
+		else:
+			display.View.Dump(plot_file.split('.')[0] + '.ppm')
+

tests/test_datasets/parameters_test_ffd_iges.prm

@@ -0,0 +1,75 @@
+
+[Box info]
+# This section collects all the properties of the FFD bounding box.
+
+# n control points indicates the number of control points in each direction (x, y, z).
+# For example, to create a 2 x 3 x 2 grid, use the following: n control points: 2, 3, 2
+n control points x: 2
+n control points y: 2
+n control points z: 2
+
+# box lenght indicates the length of the FFD bounding box along the three canonical directions (x, y, z).
+# It uses the local coordinate system.
+# For example to create a 2 x 1.5 x 3 meters box use the following: lenght box: 2.0, 1.5, 3.0
+box lenght x: 2200.0
+box lenght y: 2200.0
+box lenght z: 5100.0
+
+# box origin indicates the x, y, and z coordinates of the origin of the FFD bounding box. That is center of
+# rotation of the bounding box. It corresponds to the point coordinates with position [0][0][0].
+# See section "Parameters weights" for more details.
+# For example, if the origin is equal to 0., 0., 0., use the following: origin box: 0., 0., 0.
+box origin x: -1100.0
+box origin y: -1100.0
+box origin z: 5000.0
+
+# rotation angle indicates the rotation angle around the x, y, and z axis of the FFD bounding box in degrees.
+# The rotation is done with respect to the box origin.
+# For example, to rotate the box by 2 deg along the z direction, use the following: rotation angle: 0., 0., 2.
+rotation angle x: 0
+rotation angle y: 0
+rotation angle z: 0
+
+
+[Parameters weights]
+# This section describes the weights of the FFD control points.
+# We adopt the following convention:
+# For example with a 2x2x2 grid of control points we have to fill a 2x2x2 matrix of weights.
+# If a weight is equal to zero you can discard the line since the default is zero.
+#
+# | x index | y index | z index | weight |
+#  --------------------------------------
+# |    0    |    0    |    0    |  1.0   |
+# |    0    |    1    |    1    |  0.0   | --> you can erase this line without effects
+# |    0    |    1    |    0    | -2.1   |
+# |    0    |    0    |    1    |  3.4   |
+
+# parameter x collects the displacements along x, normalized with the box lenght x.
+parameter x: 0   0   0   0.0
+			 0   0   1   0.0
+			 0   1   0   0.0
+			 0   1   1   0.0
+			 1   0   0   0.0
+			 1   0   1   0.0
+			 1   1   0   0.0
+			 1   1   1   0.3
+
+# parameter y collects the displacements along y, normalized with the box lenght y.
+parameter y: 0   0   0   0.0
+			 0   0   1   0.0
+			 0   1   0   0.0
+			 0   1   1   0.0
+			 1   0   0   0.0
+			 1   0   1   0.0
+			 1   1   0   0.0
+			 1   1   1   0.4
+
+# parameter z collects the displacements along z, normalized with the box lenght z.
+parameter z: 0   0   0   0.0
+			 0   0   1   0.5
+			 0   1   0   0.0
+			 0   1   1   0.5
+			 1   0   0   0.0
+			 1   0   1   0.2
+			 1   1   0   0.0
+			 1   1   1   0.2