| name | ss14-transform-physics |
| description | Work with SS14 transforms, coordinates, grids, maps, anchoring, containers, movement, collision, fixtures, physics bodies, thrown entities, or spatial queries. |
SS14 Transform And Physics
Use this skill when a change moves entities, changes collision, depends on map/grid coordinates, or edits physics behavior.
Spatial code is fragile because transform, map grids, containers, and physics all interact. Prefer the established entity systems over direct component mutation.
Workflow
- Choose the right coordinate space.
- Use entity coordinates for relative positions and map coordinates for world/map-space decisions.
- Convert deliberately at system boundaries; do not compare coordinates from different maps or grids without conversion.
- Handle nullspace, deleted entities, and entities leaving PVS or containers.
- Use systems for spatial mutations.
- Prefer
SharedTransformSystem, SharedPhysicsSystem, container systems, and movement systems over direct field writes.
- Anchoring, parenting, and grid changes should go through the existing APIs so broadphase, fixtures, and dirty state stay coherent.
- Do not make shared predicted movement depend on server-only systems.
- Keep collision data data-driven.
- Prefer prototype fixture and body settings when content should tune collision.
- If code changes fixture masks, layers, density, or collision state, check the nearby component and prototype patterns.
- Respect server authority and prediction.
- Server systems own authoritative physics outcomes.
- Shared predicted code may provide local responsiveness, but must converge with server state.
- Avoid random impulses or non-deterministic client-only motion in predicted paths.
- Validate with focused coverage.
- Build affected shared/server/client projects.
- For movement or collision bugs, prefer an in-game pass or a targeted integration test when practical.
Reference Map
../ss14-prediction/SKILL.md../ss14-netcode/SKILL.md../ss14-standard-optimizations/SKILL.md../ss14-ecs-systems/SKILL.md
Good File Anchors
Content.Shared/**/Movement/**Content.Shared/**/Physics/**Content.Server/**/Movement/**Content.Server/**/Physics/**Resources/Prototypes/**
Common Pitfalls
- Mutating transform or physics component fields directly.
- Mixing map and entity coordinates without an explicit conversion.
- Forgetting containers, anchoring, or grid changes when moving entities.
- Adding client-only movement that cannot reconcile with server state.
