Geometric Contact Potential (#191)

Implementation of the SIGGRAPH 2025 paper "Geometric Contact Potential". The implementation includes the collision and friction potential, and their gradient and Hessian.

---------

Co-authored-by: Daniel Zint <[email protected]>
Co-authored-by: Zachary Ferguson <[email protected]>

Author: 3 people

.clang-tidy

@@ -8,6 +8,7 @@ Checks: >
 
   # Bug Detection and Safety
   bugprone-*,
+  # misc-const-correctness,
 
   # Specific high-value checks (even if not in a group above)
   google-runtime-int,
@@ -27,7 +28,10 @@ Checks: >
   -readability-isolate-declaration,
   -readability-magic-numbers,
   -readability-math-missing-parentheses,
-  -readability-redundant-access-specifiers
+  -readability-redundant-access-specifiers,
+  -readability-uppercase-literal-suffix,
+  -readability-function-size,
+  -readability-convert-member-functions-to-static
 
 WarningsAsErrors: '*'
 HeaderFilterRegex: '.*(ipc/).*'

.github/workflows/coverage.yml

@@ -72,7 +72,7 @@ jobs:
           lcov --remove coverage.info --ignore-errors unused '/usr/*' "$HOME/.cache/*" "*tests/*" --output-file coverage.info
 
       - name: Upload coverage reports to Codecov
-        uses: codecov/codecov-action@v3.1.6
+        uses: codecov/codecov-action@v5.5.1
         with:
           fail_ci_if_error: true
           files: build/coverage.info

.pre-commit-config.yaml

@@ -1,11 +1,11 @@
 repos:
   - repo: https://github.com/pre-commit/mirrors-clang-format
-    rev: v14.0.0
+    rev: v21.1.2
     hooks:
       - id: clang-format
         name: clang-format
         description: "Use clang-format to format C/C++ code"
-        entry: clang-format-20
+        entry: clang-format
         args:
           - --style=file
           - --verbose

CMakeLists.txt

@@ -176,6 +176,11 @@ target_link_libraries(ipc_toolkit PRIVATE simple_bvh::simple_bvh)
 include(spdlog)
 target_link_libraries(ipc_toolkit PUBLIC spdlog::spdlog)
 
+# TinyAD
+include(tinyad)
+# TODO: Make this a private dependency once we stop exposing TinyAD types in the public API.
+target_link_libraries(ipc_toolkit PUBLIC TinyAD::TinyAD)
+
 # CCD
 if(IPC_TOOLKIT_WITH_INEXACT_CCD)
   # Etienne Vouga's CTCD Library for the floating point root finding algorithm

cmake/ipc_toolkit/ipc_toolkit_tests_data.cmake

@@ -30,7 +30,7 @@ else()
         SOURCE_DIR ${IPC_TOOLKIT_TESTS_DATA_DIR}
 
         GIT_REPOSITORY https://github.com/ipc-sim/ipc-toolkit-tests-data.git
-        GIT_TAG 0c6ce752d020db32f62da37d7b8ca9f73c204b36
+        GIT_TAG 7ca6db695adcc00d3d6d978767dfc0d81722a515
 
         CONFIGURE_COMMAND ""
         BUILD_COMMAND ""

cmake/recipes/scalable_ccd.cmake

@@ -8,7 +8,7 @@ message(STATUS "Third-party: creating target 'scalable_ccd::scalable_ccd'")
 
 include(CPM)
 CPMAddPackage(
-    URI "gh:continuous-collision-detection/scalable-ccd#4fa806f533b19132e696a2dddeab16537025b5f9"
+    URI "gh:continuous-collision-detection/scalable-ccd#c80af01cab083b3eeb8dac80312ec9cfe479a5cf"
     OPTIONS "SCALABLE_CCD_WITH_CUDA ${IPC_TOOLKIT_WITH_CUDA}"
 )
 

cmake/recipes/spdlog.cmake

@@ -10,7 +10,7 @@ option(SPDLOG_INSTALL "Generate the install target" ON)
 set(CMAKE_INSTALL_DEFAULT_COMPONENT_NAME "spdlog")
 
 include(CPM)
-CPMAddPackage("gh:gabime/spdlog@1.11.0")
+CPMAddPackage("gh:gabime/spdlog@1.15.3")
 
 set_target_properties(spdlog PROPERTIES POSITION_INDEPENDENT_CODE ON)
 

cmake/recipes/tinyad.cmake

@@ -0,0 +1,16 @@
+# TinyAD (https://github.com/patr-schm/tinyad)
+# License: MIT
+if(TARGET TinyAD::TinyAD)
+    return()
+endif()
+
+message(STATUS "Third-party: creating target 'TinyAD::TinyAD'")
+
+include(CPM)
+CPMAddPackage(
+    URI "gh:zfergus/tinyad#957ede5bcf4b8d924f27230083508c664a9f7a7d"
+    OPTIONS "TINYAD_PARALLEL_BACKEND onetbb"
+)
+
+# Folder name for IDE
+set_target_properties(TinyAD PROPERTIES FOLDER "ThirdParty")

docs/source/developers/tools.rst

@@ -0,0 +1,25 @@
+Tools for Developers
+=====================
+
+Using Pre-Commit Hooks
+----------------------
+
+Use the ``.pre-commit-config.yaml`` file to apply clang-format on before commits.
+
+Steps:
+1. ``pip install pre-commit``
+2. ``pre-commit install``
+3. ``git add . && git commit -m "My commit message"``
+
+Hopefully, that will avoid upsetting the GitHub checks :slightly_smiling_face:
+
+Clang-Tidy
+----------
+
+To run locally:
+
+1. `Install clang-tidy on mac <https://stackoverflow.com/questions/53111082/how-to-install-clang-tidy-on-macos/78243685#78243685>`_
+2. ``cd build; cmake -DCMAKE_EXPORT_COMPILE_COMMANDS=ON ..``: this exports a JSON describing how all the files will be compiled
+3. ``cd ..; run-clang-tidy -quiet -p build $(find src -name '*.cpp')``
+
+You can also tack on a ``-j <N>`` to run-clang-tidy to make it parallel.

python/src/bindings.cpp

@@ -88,6 +88,8 @@ PYBIND11_MODULE(ipctk, m)
     define_smooth_friction_mollifier(m);
     define_smooth_mu(m);
 
+    define_smooth_potential(m);
+
     // implicits
     define_plane_implicit(m);