libigl_Martin/python/tutorial/704_SignedDistance.py

from __future__ import print_function

# Add the igl library to the modules search path
import sys, os
sys.path.insert(0, os.getcwd() + "/../")

import pyigl as igl
from iglhelpers import e2p
import math
TUTORIAL_SHARED_PATH = "../../tutorial/shared/"

global V, F, T, tree, FN, VN, EN, E, EMAP, max_distance, slice_z, overlay

V = igl.eigen.MatrixXd()
F = igl.eigen.MatrixXi()
T = igl.eigen.MatrixXi()
tree = igl.AABB()
FN = igl.eigen.MatrixXd()
VN = igl.eigen.MatrixXd()
EN = igl.eigen.MatrixXd()
E = igl.eigen.MatrixXi()
EMAP = igl.eigen.MatrixXi()

max_distance = 1
slice_z = 0.5
overlay = False

viewer = igl.viewer.Viewer()

def update_visualization(viewer):
    global V, F, T, tree, FN, VN, EN, E, EMAP, max_distance, slice_z, overlay
    plane = igl.eigen.MatrixXd([0.0, 0.0, 1.0, -((1-slice_z) * V.col(2).minCoeff() + slice_z * V.col(2).maxCoeff())])
    V_vis = igl.eigen.MatrixXd()
    F_vis = igl.eigen.MatrixXi()

    # Extract triangle mesh slice through volume mesh and subdivide nasty triangles
    J = igl.eigen.MatrixXi()
    bary = igl.eigen.SparseMatrixd()
    igl.slice_tets(V, T, plane, V_vis, F_vis, J, bary)
    max_l = 0.03
#    while True:
#        l = igl.eigen.MatrixXd()
#        igl.edge_lengths(V_vis, F_vis, l)
#        l /= (V_vis.colwise().maxCoeff() - V_vis.colwise().minCoeff()).norm()
#        
#        if l.maxCoeff() < max_l:
#            break
#        
#        bad = e2p(l.rowwiseMaxCoeff())
#        bad = bad > max_l
#        F_vis_bad = igl.eigen.MatrixXi()
#        F_vis_good = igl.eigen.MatrixXi()
#        igl::slice_mask(F_vis, bad, 1, F_vis_bad);
#        igl::slice_mask(F_vis, (bad!=true).eval(), 1, F_vis_good);
#        igl.upsample(V_vis, F_vis_bad)
#        F_vis = igl.cat(1, F_vis_bad, F_vis_good)


#    #Compute signed distance
#    S_vis = igl.eigen.MatrixXd()
#    I = igl.eigen.MatrixXi()
#    N = igl.eigen.MatrixXd()
#    C = igl.eigen.MatrixXd()

#    # Bunny is a watertight mesh so use pseudonormal for signing
#    igl.signed_distance_pseudonormal(V_vis, V, F, tree, FN, VN, EN, EMAP, S_vis, I, C, N)

#    # push to [0,1] range
#    S_vis.array() = 0.5*(S_vis.array()/max_distance)+0.5;
#    C_vis = igl.eigen.MatrixXi()
#    # color without normalizing
#    igl.parula(S_vis, False, C_vis)


#    const auto & append_mesh = [&C_vis,&F_vis,&V_vis](const Eigen::MatrixXd & V, const Eigen::MatrixXi & F, const RowVector3d & color)

#    F_vis.conservativeResize(F_vis.rows() + F.rows(), 3)
#    F_vis.bottomRows(F.rows()) = F.array() + V_vis.rows()
#    V_vis.conservativeResize(V_vis.rows() + V.rows(), 3)
#    V_vis.bottomRows(V.rows()) = V
#    C_vis.conservativeResize(C_vis.rows() + V.rows(), 3)
#    C_vis.bottomRows(V.rows()).rowwise() = color

#    if overlay:
#        append_mesh(V, F, RowVector3d(0.8,0.8,0.8))

    viewer.data.clear()
    viewer.data.set_mesh(V_vis, F_vis)
#    viewer.data.set_colors(C_vis)
    viewer.core.lighting_factor = overlay




def key_down(viewer, key, modifier):
    global slice_z, overlay

    if key == ord(' '):
        overlay = not overlay
    elif key == ord('.'):
        slice_z = min(slice_z + 0.01, 0.99)
    elif key == ord(','):
        slice_z = max(slice_z - 0.01, 0.01)
    else:
        return False

    update_visualization(viewer)
    return True


print("Press [space] to toggle showing surface.")
print("Press '.'/',' to push back/pull forward slicing plane.")

#Load mesh: (V,T) tet-mesh of convex hull, F contains original surface triangles
igl.readMESH(TUTORIAL_SHARED_PATH + "bunny.mesh", V, T, F);

#Call to point_mesh_squared_distance to determine bounds
sqrD = igl.eigen.MatrixXd()
I = igl.eigen.MatrixXi()
C = igl.eigen.MatrixXd()
igl.point_mesh_squared_distance(V, V, F, sqrD, I, C)
max_distance = math.sqrt(sqrD.maxCoeff())

#Precompute signed distance AABB tree
tree.init(V, F)

#Precompute vertex, edge and face normals
igl.per_face_normals(V, F, FN)
igl.per_vertex_normals(V, F, igl.PER_VERTEX_NORMALS_WEIGHTING_TYPE_ANGLE, FN, VN)
igl.per_edge_normals(V, F, igl.PER_EDGE_NORMALS_WEIGHTING_TYPE_UNIFORM, FN, EN, E, EMAP)

#Plot the generated mesh
update_visualization(viewer);
viewer.callback_key_down = key_down
viewer.core.show_lines = False
viewer.launch()