# st-tech/ppf-contact-solver

A contact solver for physics-based simulations involving 👚 shells, 🪵 solids, 🪢 rods, 🧱 rigid bodies and ⏳ sand.

Repository: https://github.com/st-tech/ppf-contact-solver
Canonical: https://ross.abutalabs.com/products/ppf-contact-solver
Language: Python
License: Apache-2.0
License Family: permissive
Topics: cloth, collision, contact, physics, simulation
Last push: 2026-08-19T11:05:36+00:00

## Health v2 (maintenance only)
Score: 87/100 (v2, computed 2026-09-03T02:39:23.370411+00:00)
- activity 98, release rhythm 97, longevity 46
- inputs: {"age_days": 651, "days_push": 14, "days_rel": 21, "gap_med": 0.0, "n_releases_24m": 31}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 4446, forks 327 (observed 2026-08-28T04:08:50.397255+00:00)

## What it is
A GPU-accelerated contact solver for physics-based simulations of shells (cloth), solids, rods, rigid bodies, and sand, originally developed in-house at ZOZO, Inc. It provides a Python API, a Blender add-on for remote simulation, and Docker-based setup for running examples.

## Use cases
- simulate cloth and garment physics on GPU
- resolve contacts between rigid bodies without penetration
- simulate rods, solids, and granular sand materials
- run physics simulations from Blender
- simulate large-scale scenes with hundreds of millions of contacts

## When to choose
- you need penetration-free contact resolution for cloth or deformable bodies
- you need GPU-accelerated physics with very large contact counts
- you want to simulate garments for fashion or e-commerce visualization
- you want a Blender-integrated physics solver

## When to avoid
- you need a general-purpose game engine with rendering and audio
- you have no NVIDIA GPU and cannot use Docker
- you need CPU-only double-precision simulation
- you need soft-body physics beyond shells, solids, rods, rigid bodies, and sand

## Facets
- artifact type: library
- maturity: active
- function: simulation, graphics, gpu-computing
- domain: simulation, graphics, gpu-computing
- platform: windows, python
- tags: cloth-simulation, contact-solver, physics-engine, gpu, blender-addon, rust, collision-detection, physics, game-development, linux, docker

## Member repositories
- st-tech/ppf-contact-solver (main) score 87

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:08:50.397255+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T18:20:48.248760+00:00, confidence not recorded.
  - readme: https://github.com/st-tech/ppf-contact-solver (fetched 2026-08-28T04:08:50.397255+00:00, sha f050a59bb767)
- Data as of 2026-08-30T08:39:29.467469+00:00.