Scent fixes

[Sparlight]

Short description

Day one fixes for ScentSystem.

Why we need to add this

Consistent and sensible logic for this system is important.

Media (Video/Screenshots)

(all fixes tested/verified; rollerbed clip shown here)
(also tested making a long dispo loop and verifying no new scent emissions once flushed)
(also tested having a terror spider with attached ScentComponent in dispo pipes)
(also tested replays)

Scents no longer stick to the rollerbed:

Myserver.-.Starlight.2026-08-03.13-26-11.mp4

Scents now only show up if a vent crawler is at a pipe system terminus:

2026-08-03.13-59-11.mp4

Scents now no longer show up in replays:

Starlight.2026-08-03.21-00-32.mp4

Checks

• I do not require assistance to complete the PR.
• Before posting/requesting review of a PR, I have verified that the changes work.
• I have added screenshots/videos of the changes, or this PR does not change in-game mechanics.
• I affirm that my changes are licensed under the MIT License and grant permission for use in this repository under its conditions.

Changelog

🆑 Sparlight

• tweak: Dying makes you lose your currently-tracked scent.
• fix: Scent emissions now no longer get stuck on mechs/rollerbeds.
• fix: Scent emissions no longer travel down disposal tubes and emit while being disposed.
• fix: Scent emissions no longer emit from vent-crawling entities unless they are at a vent terminus.
• fix: Scents no longer appear in replays.

[coderabbitai]

Caution

Review failed

The head commit changed during the review from 35c2bcc to 019e19a.

📝 Walkthrough

Walkthrough

Scent markers now record their airtight container. Emission excludes disposed entities and hidden vent-crawl entities. Client tracking uses current containment. Dead smellers lose tracked scent when their mob state changes to Dead.

Changes

Scent lifecycle

Layer / File(s)	Summary
Containment-aware scent emission Content.Shared/_Starlight/Scent/Components/ScentMarkerComponent.cs, Content.Server/_Starlight/Scent/Systems/ScentSystem.cs	Markers replace WasContained with ContainedIn. Emission filters disposed and hidden vent-crawl entities, records airtight containment, and refreshes it during merging.
Current containment marker tracking Content.Client/_Starlight/Scent/Systems/ScentTrackingSystem.cs	Markers are hidden without a local SmellerComponent. Visibility, enclosure comparison, and marker sizing use ContainedIn.
Dead smeller cleanup Content.Shared/_Starlight/Scent/Systems/SharedScentSystem.cs	Tracked scent is cleared when a smeller becomes Dead.

Estimated code review effort: 3 (Moderate) | ~20 minutes

Sequence Diagram(s)

sequenceDiagram
  participant Entity
  participant ScentSystem
  participant ScentMarkerComponent
  Entity->>ScentSystem: Emit scent
  ScentSystem->>ScentSystem: Check disposal and hidden vent-crawl state
  ScentSystem->>ScentSystem: GetAirtightContainer
  ScentSystem->>ScentMarkerComponent: SpawnAtPosition and set ContainedIn

Loading

Suggested reviewers: redmushie

🚥 Pre-merge checks | ✅ 6 | ❌ 2

❌ Failed checks (1 warning, 1 inconclusive)

Check name	Status	Explanation	Resolution
No Magic Numbers	⚠️ Warning	The scent fixes are well targeted, but the systems still use un-named thresholds: 8, 360, 0.85f, 0.1f, and freshness factors 4f/2f/3f.	Extract scent-ID length, fade minimum, hue range, saturation, and freshness thresholds into clearly named shared or system constants.
Avoid Service Locator	❓ Inconclusive	The repository state requires parent comparison to distinguish pre-existing service resolution from code introduced by this pull request.	No verdict yet.

✅ Passed checks (6 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly identifies the pull request as a set of scent-related fixes and matches the main changes.
Description check	✅ Passed	The description accurately summarizes the scent fixes, testing performed, and gameplay effects.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
No Hardcoded Ecs Parameters	✅ Passed	The PR adds no hardcoded tuning values; it uses existing component state and the networked [DataField] ContainedIn field, while configurable scent values remain in ScentComponent.

✨ Finishing Touches 💡 1

🛠️ Fix failing CI checks 💡

• Create stacked PR
• Commit on current branch

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@Content.Server/_Starlight/Scent/Systems/ScentSystem.cs`:
- Line 451: Update the marker creation in the scent emission flow around
SpawnAtPosition to pass the map-space position from
ToMapCoordinates(xform.Coordinates).Position instead of EntityCoordinates.
Preserve ContainedIn solely as emission metadata and do not attach the spawned
marker to the emitter’s parent.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Repository UI (base), Organization UI (inherited)

Review profile: CHILL

Plan: Pro Plus

Run ID: b8fb4102-d6a6-4261-b24f-72702a89ca2e

📥 Commits

Reviewing files that changed from the base of the PR and between cfc147e and c90df0e.

📒 Files selected for processing (4)

• Content.Client/_Starlight/Scent/Systems/ScentTrackingSystem.cs
• Content.Server/_Starlight/Scent/Systems/ScentSystem.cs
• Content.Shared/_Starlight/Scent/Components/ScentMarkerComponent.cs
• Content.Shared/_Starlight/Scent/Systems/SharedScentSystem.cs

[github-actions]

This pull request has conflicts, please resolve those before we can evaluate the pull request.

[Sparlight]

Ran the tests locally, seems like we ran into a shard 5 flake. Gonna try rerunning CI tests.