| // This file is part of libigl, a simple c++ geometry processing library. | |
| // | |
| // Copyright (C) 2018 Zhongshi Jiang <jiangzs@nyu.edu> | |
| // | |
| // 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/. | |
| namespace igl | |
| { | |
| namespace triangle | |
| { | |
| // Use a similar interface to igl::slim | |
| // Implement ready-to-use 2D version of the algorithm described in | |
| // SCAF: Simplicial Complex Augmentation Framework for Bijective Maps | |
| // Zhongshi Jiang, Scott Schaefer, Daniele Panozzo, ACM Trancaction on Graphics (Proc. SIGGRAPH Asia 2017) | |
| // For a complete implementation and customized UI, please refer to https://github.com/jiangzhongshi/scaffold-map | |
| struct SCAFData | |
| { | |
| double scaffold_factor = 10; | |
| igl::MappingEnergyType scaf_energy = igl::MappingEnergyType::SYMMETRIC_DIRICHLET; | |
| igl::MappingEnergyType slim_energy = igl::MappingEnergyType::SYMMETRIC_DIRICHLET; | |
| // Output | |
| int dim = 2; | |
| double total_energy; // scaffold + isometric | |
| double energy; // objective value | |
| long mv_num = 0, mf_num = 0; | |
| long sv_num = 0, sf_num = 0; | |
| long v_num{}, f_num = 0; | |
| Eigen::MatrixXd m_V; // input initial mesh V | |
| Eigen::MatrixXi m_T; // input initial mesh F/T | |
| // INTERNAL | |
| Eigen::MatrixXd w_uv; // whole domain uv: mesh + free vertices | |
| Eigen::MatrixXi s_T; // scaffold domain tets: scaffold tets | |
| Eigen::MatrixXi w_T; | |
| Eigen::VectorXd m_M; // mesh area or volume | |
| Eigen::VectorXd s_M; // scaffold area or volume | |
| Eigen::VectorXd w_M; // area/volume weights for whole | |
| double mesh_measure = 0; // area or volume | |
| double proximal_p = 0; | |
| Eigen::VectorXi frame_ids; | |
| Eigen::VectorXi fixed_ids; | |
| std::map<int, Eigen::RowVectorXd> soft_cons; | |
| double soft_const_p = 1e4; | |
| Eigen::VectorXi internal_bnd; | |
| Eigen::MatrixXd rect_frame_V; | |
| // multi-chart support | |
| std::vector<int> component_sizes; | |
| std::vector<int> bnd_sizes; | |
| // reweightedARAP interior variables. | |
| bool has_pre_calc = false; | |
| Eigen::SparseMatrix<double> Dx_s, Dy_s, Dz_s; | |
| Eigen::SparseMatrix<double> Dx_m, Dy_m, Dz_m; | |
| Eigen::MatrixXd Ri_m, Ji_m, Ri_s, Ji_s; | |
| Eigen::MatrixXd W_m, W_s; | |
| }; | |
| // Compute necessary information to start using SCAF | |
| // Inputs: | |
| // V #V by 3 list of mesh vertex positions | |
| // F #F by 3/3 list of mesh faces (triangles/tets) | |
| // data igl::SCAFData | |
| // slim_energy Energy type to minimize | |
| // b list of boundary indices into V (soft constraint) | |
| // bc #b by dim list of boundary conditions (soft constraint) | |
| // soft_p Soft penalty factor (can be zero) | |
| IGL_INLINE void scaf_precompute( | |
| const Eigen::MatrixXd &V, | |
| const Eigen::MatrixXi &F, | |
| const Eigen::MatrixXd &V_init, | |
| triangle::SCAFData &data, | |
| MappingEnergyType slim_energy, | |
| Eigen::VectorXi& b, | |
| Eigen::MatrixXd& bc, | |
| double soft_p); | |
| // Run iter_num iterations of SCAF, with precomputed data | |
| // Outputs: | |
| // V_o (in SLIMData): #V by dim list of mesh vertex positions | |
| IGL_INLINE Eigen::MatrixXd scaf_solve(triangle::SCAFData &data, int iter_num); | |
| // Set up the SCAF system L * uv = rhs, without solving it. | |
| // Inputs: | |
| // s: igl::SCAFData. Will be modified by energy and Jacobian computation. | |
| // Outputs: | |
| // L: m by m matrix | |
| // rhs: m by 1 vector | |
| // with m = dim * (#V_mesh + #V_scaf - #V_frame) | |
| IGL_INLINE void scaf_system(triangle::SCAFData &s, Eigen::SparseMatrix<double> &L, Eigen::VectorXd &rhs); | |
| namespace scaf | |
| { | |
| // Compute SCAF energy | |
| // Inputs: | |
| // s: igl::SCAFData | |
| // w_uv: (#V_mesh + #V_scaf) by dim matrix | |
| // whole: Include scaffold if true | |
| IGL_INLINE double compute_energy(SCAFData &s, const Eigen::MatrixXd &w_uv, bool whole); | |
| } | |
| } | |
| } | |