Beispiel #1
0
 def test_remove_mesh_boundary_faces(self):
     mesh_a = self.cutSphere_A.copy()
     mesh_a_save = mesh_a.copy()
     boundary = stop.mesh_boundary(mesh_a)
     mesh_processed = stop.remove_mesh_boundary_faces(mesh_a,
                                                      face_vertex_number=1)
     # Non modification
     assert (mesh_a.vertices == mesh_a_save.vertices).all()
     # Correctness
     # check that when removing all faces with any vertex on the boundary,
     # all the boundary vertices are removed from the mesh
     print(len(boundary[0]))
     print(len(mesh_a.vertices))
     print(len(mesh_processed.vertices))
     assert (len(mesh_processed.vertices) == len(mesh_a.vertices) -
             len(boundary[0]))
Beispiel #2
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def generate_paraboloid_regular(A, nstep=50, ax=1, ay=1,
                                random_sampling=False,
                                random_distribution_type='gaussian',
                                ratio=0.1):
    """
        generate a regular paraboloid mesh Z=K*Y^2
        ratio and random_distribution_type parameters are unused if
        random_sampling is set to False
        :param A: amplitude of the paraboloid
        :param nstep: nstepx or the sampling step stepx as a float !
        :param ax: half length of the domain
        :param ay: half width of the domain
        :param random_sampling:
        :param random_distribution_type:
        :param ratio:
        :return:
        """
    # Parameters
    xmin, xmax = [-ax, ax]
    ymax = ay    # ymin, ymax = [-ay, ay]
    # Define the sampling
    if isinstance(nstep, int):
        stepx = (xmax - xmin) / nstep
    else:
        stepx = nstep

    # Coordinates
    x = np.arange(xmin, xmax, stepx)
    # To generate y
    y, curve_samples = adaptive_sampling(ymax, A, stepx)

    X, Y = np.meshgrid(x, y)
    X[::2] += stepx / 2
    X = X.flatten()
    Y = Y.flatten()

    # Random perturbation
    if random_sampling:
        sigma = stepx * ratio  # characteristic size of the mesh * ratio
        nb_vert = len(x) * len(y)
        if random_distribution_type == 'gamma':
            theta = np.random.rand(nb_vert, ) * np.pi * 2
            mean = sigma
            variance = sigma ** 2
            radius = \
                np.random.gamma(mean ** 2 / variance, variance / mean, nb_vert)
            X = X + radius * np.cos(theta)
            Y = Y + radius * np.sin(theta)
        elif random_distribution_type == 'uniform':
            X = X + np.random.uniform(-1, 1, 100)
            Y = Y + np.random.uniform(-1, 1, 100)
        else:
            X = X + sigma * np.random.randn(nb_vert, )
            Y = Y + sigma * np.random.randn(nb_vert, )

    # Delaunay triangulation: be careful, to do on the curvilinear aspects to
    # avoid triangle flips
    Xtmp, S = np.meshgrid(x, curve_samples)
    S = S.flatten()
    # faces_tri = Triangulation(X, S)
    faces_tri = Delaunay(np.vstack((X, S)).T, qhull_options='QJ Qt Qbb')
    # alternative setting? 'Qbb Qc Qz Qj'

    Z = quadric(0, A)(X, Y)
    coords = np.array([X, Y, Z]).transpose()

    paraboloid_mesh = trimesh.Trimesh(faces=faces_tri.simplices,
                                      vertices=coords,
                                      process=False)
    # remove the faces having any vertex on the boundary to avoid
    # atypical faces geometry due to Delaunay triangulation in 2D
    # TO DO: same boundary removal as for generate_quadric
    return stop.remove_mesh_boundary_faces(paraboloid_mesh,
                                           face_vertex_number=1)
Beispiel #3
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visb_sc = splt.visbrain_plot(mesh=open_mesh, caption='open mesh')
# create points with vispy
for bound in open_mesh_boundary:
    points = open_mesh.vertices[bound]
    s_rad = SourceObj('rad', points, color='red', symbol='square',
                      radius_min=10)
    visb_sc.add_to_subplot(s_rad)
    lines = Line(pos=open_mesh.vertices[bound], width=10, color='b')
    # wrap the vispy object using visbrain
    l_obj = VispyObj('line', lines)
    visb_sc.add_to_subplot(l_obj)
visb_sc.preview()

###############################################################################
# eroding the mesh by removing the faces having 3 vertices on the boundary
eroded_mesh = stop.remove_mesh_boundary_faces(open_mesh, face_vertex_number=1)

###############################################################################
# show the result
visb_sc2 = splt.visbrain_plot(mesh=eroded_mesh, caption='eroded mesh')
# show again the boundary of original mesh which have been removed with
# corresponding faces by the erosion
for bound in open_mesh_boundary:
    points = open_mesh.vertices[bound]
    s_rad = SourceObj('rad', points, color='red', symbol='square',
                      radius_min=10)
    visb_sc2.add_to_subplot(s_rad)
    lines = Line(pos=open_mesh.vertices[bound], width=10, color='b')
    # wrap the vispy object using visbrain
    l_obj = VispyObj('line', lines)
    visb_sc2.add_to_subplot(l_obj)