Files
igl/python/tutorial/401_BiharmonicDeformation.py
T

123 lines
3.6 KiB
Python
Executable File

#!/usr/bin/env python
#
# This file is part of libigl, a simple c++ geometry processing library.
#
# Copyright (C) 2017 Sebastian Koch <s.koch@tu-berlin.de> and Daniele Panozzo <daniele.panozzo@gmail.com>
#
# This Source Code Form is subject to the terms of the Mozilla Public License
# v. 2.0. If a copy of the MPL was not distributed with this file, You can
# obtain one at http://mozilla.org/MPL/2.0/.
import sys, os
# Add the igl library to the modules search path
sys.path.insert(0, os.getcwd() + "/../")
import pyigl as igl
from shared import TUTORIAL_SHARED_PATH, check_dependencies
dependencies = ["glfw"]
check_dependencies(dependencies)
bc_frac = 1.0
bc_dir = -0.03
deformation_field = False
V = igl.eigen.MatrixXd()
U = igl.eigen.MatrixXd()
V_bc = igl.eigen.MatrixXd()
U_bc = igl.eigen.MatrixXd()
# Z = igl.eigen.MatrixXd()
F = igl.eigen.MatrixXi()
b = igl.eigen.MatrixXi()
def pre_draw(viewer):
global bc_frac, bc_dir, deformation_field, V, U, V_bc, U_bc, F, b
# Determine boundary conditions
if (viewer.core().is_animating):
bc_frac += bc_dir
bc_dir *= (-1.0 if bc_frac >= 1.0 or bc_frac <= 0.0 else 1.0)
U_bc_anim = V_bc + bc_frac * (U_bc - V_bc)
if (deformation_field):
D = igl.eigen.MatrixXd()
D_bc = U_bc_anim - V_bc
igl.harmonic(V, F, b, D_bc, 2, D)
U = V + D
else:
igl.harmonic(V, F, b, U_bc_anim, 2, U)
viewer.data().set_vertices(U)
viewer.data().compute_normals()
return False
def key_down(viewer, key, mods):
global bc_frac, bc_dir, deformation_field, V, U, V_bc, U_bc, F, b
if key == ord(' '):
viewer.core().is_animating = not viewer.core().is_animating
return True
if key == ord('D') or key == ord('d'):
deformation_field = not deformation_field
return True
return False
igl.readOBJ(TUTORIAL_SHARED_PATH + "decimated-max.obj", V, F)
U = igl.eigen.MatrixXd(V)
# S(i) = j: j<0 (vertex i not in handle), j >= 0 (vertex i in handle j)
S = igl.eigen.MatrixXd()
igl.readDMAT(TUTORIAL_SHARED_PATH + "decimated-max-selection.dmat", S)
S = S.castint()
b = igl.eigen.MatrixXd([[t[0] for t in [(i, S[i]) for i in range(0, V.rows())] if t[1] >= 0]]).transpose().castint()
# Boundary conditions directly on deformed positions
U_bc.resize(b.rows(), V.cols())
V_bc.resize(b.rows(), V.cols())
for bi in range(0, b.rows()):
V_bc.setRow(bi, V.row(b[bi]))
if S[b[bi]] == 0:
# Don't move handle 0
U_bc.setRow(bi, V.row(b[bi]))
elif S[b[bi]] == 1:
# Move handle 1 down
U_bc.setRow(bi, V.row(b[bi]) + igl.eigen.MatrixXd([[0, -50, 0]]))
else:
# Move other handles forward
U_bc.setRow(bi, V.row(b[bi]) + igl.eigen.MatrixXd([[0, 0, -25]]))
# Pseudo-color based on selection
C = igl.eigen.MatrixXd(F.rows(), 3)
purple = igl.eigen.MatrixXd([[80.0 / 255.0, 64.0 / 255.0, 255.0 / 255.0]])
gold = igl.eigen.MatrixXd([[255.0 / 255.0, 228.0 / 255.0, 58.0 / 255.0]])
for f in range(0, F.rows()):
if (S[F[f, 0]]) >= 0 and S[F[f, 1]] >= 0 and S[F[f, 2]] >= 0:
C.setRow(f, purple)
else:
C.setRow(f, gold)
# Plot the mesh with pseudocolors
viewer = igl.glfw.Viewer()
viewer.data().set_mesh(U, F)
viewer.data().show_lines = False
viewer.data().set_colors(C)
# viewer.core().trackball_angle = igl.eigen.Quaterniond(sqrt(2.0),0,sqrt(2.0),0)
# viewer.core().trackball_angle.normalize()
viewer.callback_pre_draw = pre_draw
viewer.callback_key_down = key_down
viewer.core().animation_max_fps = 30.0
print("Press [space] to toggle deformation.")
print("Press 'd' to toggle between biharmonic surface or displacements.")
viewer.launch()