Function map_vertex_attribute

python/pymesh/map_attributes.py:6–49

Map vertex attribute from mesh1 to mesh2 based on closest points. Args: mesh1 (:class:`Mesh`): Source mesh, where the attribute is defined. mesh2 (:class:`Mesh`): Target mesh, where the attribute is mapped to. attr_name (``string``): Attribute name. bvh (:class:

(mesh1, mesh2, attr_name, bvh=None)

from .aabb_tree import BVH

def map_vertex_attribute(mesh1, mesh2, attr_name, bvh=None):
    """ Map vertex attribute from mesh1 to mesh2 based on closest points.

    Args:
        mesh1 (:class:`Mesh`): Source mesh, where the attribute is defined.
        mesh2 (:class:`Mesh`): Target mesh, where the attribute is mapped to.
        attr_name (``string``): Attribute name.
        bvh (:class:`BVH`): Pre-computed Bounded volume hierarchy if available.

    A new attribute with name ``attr_name`` is added to ``mesh2``.
    """

    assert(mesh1.dim == mesh2.dim)
    assert(mesh1.vertex_per_face == 3)
    assert(mesh2.vertex_per_face == 3)
    assert(mesh1.has_attribute(attr_name))
    values = mesh1.get_vertex_attribute(attr_name)

    if bvh is None:
        bvh = BVH(dim=mesh1.dim)
        bvh.load_mesh(mesh1)
    dists, closest_faces, p = bvh.lookup(mesh2.vertices)

    vertices = mesh1.vertices
    faces = mesh1.faces
    v0 = vertices[faces[closest_faces,0],:]
    v1 = vertices[faces[closest_faces,1],:]
    v2 = vertices[faces[closest_faces,2],:]

    a01 = np.linalg.norm(np.cross(v0-p, v1-p), axis=1).reshape((-1,1))
    a12 = np.linalg.norm(np.cross(v1-p, v2-p), axis=1).reshape((-1,1))
    a20 = np.linalg.norm(np.cross(v2-p, v0-p), axis=1).reshape((-1,1))

    a = a01 + a12 + a20

    val_0 = values[faces[closest_faces, 0],:]
    val_1 = values[faces[closest_faces, 1],:]
    val_2 = values[faces[closest_faces, 2],:]

    target_val = (val_0 * a12 + val_1 * a20 + val_2 * a01) / a

    if not mesh2.has_attribute(attr_name):
        mesh2.add_attribute(attr_name)
    mesh2.set_attribute(attr_name, target_val)


def map_face_attribute(mesh1, mesh2, attr_name, bvh=None):