Port PebbleGame3D to solver/datagen/pebble_game.py #2

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forbes · 2026-02-02T19:32:03Z

forbes commented

2026-02-02 19:32:03 +00:00

Summary

Move PebbleGame3D class from data/synthetic/pebble-game.py (L130-367) into solver/datagen/pebble_game.py.

Class overview

The (6,6)-pebble game tests Tay sparsity conditions incrementally for 3D body-bar-hinge rigidity. Each vertex (rigid body) starts with K=6 pebbles. To insert an edge, L+1=7 pebbles must be collected on its two endpoints. If successful, the edge is independent; otherwise redundant.

Methods to port

__init__ — initializes PebbleState, edge counter, body set
add_body(body_id) — registers body with 6 free pebbles
add_joint(joint) — expands joint to multigraph edges, tests each
_try_insert_edge(edge_id, u, v) — core pebble collection + edge acceptance
_search_and_collect(target, forbidden) — DFS to find/move free pebbles
_reverse_path(edge_ids, pebble_source) — reverses directed edges along path
get_dof(), get_internal_dof(), is_rigid(), get_redundant_count()
classify_assembly(grounded) — returns well-constrained/under/over/mixed

Requirements

Import types from solver.datagen.types (JointType, Joint, PebbleState)
Full type annotations on all methods
Preserve algorithm docstrings and references (Lee & Streinu, Tay)
No behavioral changes
__all__ = ["PebbleGame3D"]

Depends on

#1 (shared types)

## Summary Move `PebbleGame3D` class from `data/synthetic/pebble-game.py` (L130-367) into `solver/datagen/pebble_game.py`. ## Class overview The (6,6)-pebble game tests Tay sparsity conditions incrementally for 3D body-bar-hinge rigidity. Each vertex (rigid body) starts with K=6 pebbles. To insert an edge, L+1=7 pebbles must be collected on its two endpoints. If successful, the edge is independent; otherwise redundant. ## Methods to port - `__init__` — initializes `PebbleState`, edge counter, body set - `add_body(body_id)` — registers body with 6 free pebbles - `add_joint(joint)` — expands joint to multigraph edges, tests each - `_try_insert_edge(edge_id, u, v)` — core pebble collection + edge acceptance - `_search_and_collect(target, forbidden)` — DFS to find/move free pebbles - `_reverse_path(edge_ids, pebble_source)` — reverses directed edges along path - `get_dof()`, `get_internal_dof()`, `is_rigid()`, `get_redundant_count()` - `classify_assembly(grounded)` — returns well-constrained/under/over/mixed ## Requirements - [ ] Import types from `solver.datagen.types` (JointType, Joint, PebbleState) - [ ] Full type annotations on all methods - [ ] Preserve algorithm docstrings and references (Lee & Streinu, Tay) - [ ] No behavioral changes - [ ] `__all__ = ["PebbleGame3D"]` ## Depends on - #1 (shared types)

forbes added the phase:1 port labels 2026-02-02 19:32:03 +00:00

forbes referenced this issue

2026-02-02 19:32:27 +00:00

Port analyze_assembly to solver/datagen/analysis.py #4

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2026-02-02 19:33:37 +00:00

Ground truth labeling pipeline #9

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2026-02-02 19:47:39 +00:00

feat: port PebbleGame3D to solver/datagen/pebble_game.py

forbes closed this issue

2026-02-02 19:47:39 +00:00