v1.4.0

Highlights

• Add adhesion potentials for sticky interactions, allowing for more realistic simulations of contact between objects.
  • Based on the paper "Augmented Incremental Potential Contact for Sticky Interactions" by Fang et al. [2023]
• Implement new barrier functions from the literature.
  • NormalizedClampedLogBarrier: unit-less clamped log barrier function.
  • ClampedLogSqBarrier: clamped log barrier with a quadratic log term from [Huang et al. 2024]
  • CubicBarrier: cubic barrier function from [Ando 2024]
• Add support for separate static and kinetic coefficients in tangential collisions.

What's Changed

• Adhesion by @zfergus in #85
  • Implement the adhesion potentials from "Augmented Incremental Potential Contact for Sticky Interactions" [Fang et al. 2023]
  • Files moved from ipc/friction to generic ipc/tangential and ipc/collisions/tangential folders.
  • Renamed Collision classes to NormalCollision
  • Renamed FrictionCollision classes to TangentialCollision
  • Renamed DistanceBasedPotential to NormalPotential
    • Added force_magnitude and force_magnitude_gradient methods to NormalPotential
  • Added TangentialPotential parent class to FrictionPotential and TangentialAdhesionPotential
  • Tutorial added by @antoinebou12 in #144
  • Use normal potential in tangential collisions by @maxpaik16 in #142
    • Replaces the const BarrierPotential& parameter with a const NormalPotential&
    • This allows tangential adhesion to be properly set up in simulation.
• Add NormalizedClampedLogBarrier by @zfergus in #143
• Add max_iterations parameter to Additive CCD by @zfergus in #145
• Add cubic barrier with elasticity-inclusive dynamic stiffness by @zfergus in #148
  • Implement the cubic barrier and elasticity-inclusive dynamic stiffness from [Ando 2024]
  • Implement $log^2$-barrier from GIPC [Huang et al. 2024]
  • Add compute_coefficients() to CollisionStencil – computes the coefficients $\vec{c}$ s.t. $d(x) = \Vert \sum c_i x_i\Vert^2$
  • Add compute_distance() to CollisionStencil taking $V$, $E$, $F$ directly
• Replace BroadPhaseMethod enum with shared_ptr<BroadPhase> by @zfergus in #152
  • Python BroadPhase by @zfergus in #155
• Remove ContinuousCollisionCandidate inheritance by @zfergus in #156
  • Replace it with the CollisionStencil class.
• Replace const Eigen::Matrix& with Eigen::ConstRef<Matrix> by @zfergus in #157
  • This allows for more efficient passing of matrices to functions.
• Separate Static and Kinetic Coefficients of Friction by @zfergus in #177
  • Enhancements to tangential collision handling by distinguishing between static and kinetic friction coefficients (mu_s and mu_k) and implementing smooth transitions between them.
  • Updated TangentialCollision class to replace mu with separate mu_s (static friction coefficient) and mu_k (kinetic friction coefficient). This change applies to the class definition and all related methods.
  • New smooth_mu functions: Added functions to compute smooth transitions between static and kinetic friction coefficients, including derivatives and related mathematical formulations. These functions improve the modeling of friction forces at varying tangential velocities.
  • Integration with adhesion module: Incorporated smooth friction coefficient calculations into the adhesion module.
  • Tutorial added by @zfergus in #178

Python Specific

• Add faster can_collide functions to Python by @zfergus in #135
• Add PyBroadPhase and PyNarrowPhaseCCD classes to wrap the BroadPhase and NarrowPhaseCCD classes, respectively, allowing for custom implementations of these classes in Python.
• Add new constructors to candidate classes (EdgeEdgeCandidate, EdgeFaceCandidate, EdgeVertexCandidate, FaceFaceCandidate, FaceVertexCandidate, VertexVertexCandidate) that accept tuples for easier initialization.
• Include a call to std::atexit to reset the thread limiter upon program exit to ensure proper cleanup.
• ⚠️ Python NarrowPhaseCCD implementations will not work with multi-threading because of GIL locking.
• Switch from py::arg to _a literals by @zfergus in #168

Miscellaneous

• Add /Wall and /MP compiler flags for MSVC by @zfergus in #134
• Enable CUDA by default if CUDA is detected by CMake by @zfergus in #134
• Devcontainer by @antoinebou12 in #136
• Update dependencies for CMake 4.0 by @zfergus in #158
• Organize folder structure for generated Xcode project by @zfergus in #159
  • Refactor CMake configurations and improve project structure
  • Updated CMake recipes for third-party libraries to set appropriate folder properties for IDE organization.
  • Changed the CPMAddPackage references for scalable-ccd to a more recent commit.
  • Enhanced logging functionality by adding a new log_and_throw_error function to improve error handling.
  • Improved documentation in the style guide for naming conventions.
  • Move generated config.hpp file from src/ipc to build/include/src/ipc
  • Update CUDA builds in CMakePresets.json
  • Remove virtual tag from BroadPhase::detect_collision_candidates
• Index typedef by @zfergus in #161
  • Add a index_t typedef for vertex/edge/face ids. Changes default from long to int32_t.
• Update Tight Inclusion package version to 1.0.6 by @zfergus in #165
• Fix cmake for non-top-level inclusion by @sin3point14 in #167
• Improve and clean up documentation:
  • Fix Error in Docs by @zfergus in #169
  • Update docs by @zfergus in #173
  • Update docs.yml by @zfergus in #174
  • Refactor and clean-up C++ API docs by @zfergus in #175

New Contributors

• @maxpaik16 made their first contribution in #142
• @sin3point14 made their first contribution in #167

Full Changelog: v1.3.1...v1.4.0