# BRIEFING — 2026-10-01T19:26:00Z

## Mission
Investigate client-side rendering, isometric math, collision, fog of war, minimap, mobile performance, and monster systems for tile grid migration in FreeExile.

## 🔒 My Identity
- Archetype: explorer
- Roles: Client Map Explorer, read-only investigation, architectural synthesis
- Working directory: c:\Projects\FreeExile\.agents\teamwork\explorer_survey_client
- Original parent: 1cc48fc5-ce57-4f48-8964-24cab4bfcacc
- Milestone: Wilderness Tile Grid & Map System Survey

## 🔒 Key Constraints
- Read-only investigation — do NOT implement
- Write only to own folder (`c:\Projects\FreeExile\.agents\teamwork\explorer_survey_client`)
- Produce comprehensive report at `report.md` and handoff at `handoff.md`
- Send final completion message to caller via `send_message`

## Current Parent
- Conversation ID: 1cc48fc5-ce57-4f48-8964-24cab4bfcacc
- Updated: not yet

## Investigation State
- **Explored paths**:
  - `client/webapp/js/engine/world_renderer.js` (Lines 1–461)
  - `client/webapp/js/engine/iso_math.js` (Lines 1–426)
  - `client/webapp/js/engine/canvas_renderer.js` (Lines 1–325)
  - `client/webapp/js/engine/entity_renderer.js` (Lines 1–431)
  - `client/webapp/js/engine/collision_engine.js` (Lines 1–218)
  - `client/webapp/js/engine/monster_system.js` (Lines 1–486)
  - `client/webapp/js/data/wilderness_zone_packs.js` (Lines 1–254)
  - `client/webapp/index.html` (Lines 1–198)
  - `server/world/map_data_types.py` & `server/world/procedural_map_engine.py`
  - `tests/unit/test_war_fog_and_procedural_map.py`
- **Key findings**:
  - World renderer lines 12–28 run a 2,025-iteration math formula loop every frame; can be replaced with view-culling frustum tile rendering.
  - 1 world unit = 1 tile isometric; `tx = Math.floor(wx)`, `ty = Math.floor(wy)` gives direct 1:1 mapping with no coordinate translation.
  - Upgrading `isPositionBlocked(wx, wy)` in `collision_engine.js` automatically enables 2-axis wall sliding along tile walls and locked boss gates without touching character physics.
  - Full chunk pre-rendering of 48 chunks would consume 96 MB RAM; an LRU bounded active pool of 3–4 `OffscreenCanvas` instances guarantees the $\le 8$ MB RAM budget while cutting draw calls by $> 98\%$.
  - Top-right HUD space at `top-12 right-3` in `index.html` is completely unencumbered for the 120×80 Minimap canvas.
- **Unexplored areas**: None within client scope. Ready for handoff.

## Key Decisions Made
- Confirmed that coordinate system direct mapping (`floor(wx), floor(wy)`) is optimal.
- Designed the LRU bounded chunk cache pool to solve the 96 MB vs 8 MB mobile constraint.
- Formulated Fog of War masking inside `entity_renderer.js` to suppress monster rendering in `EXPLORED_FOGGED` tiles.

## Artifact Index
- `c:\Projects\FreeExile\.agents\teamwork\explorer_survey_client\DISPATCH.md` — Assignment instructions
- `c:\Projects\FreeExile\.agents\teamwork\explorer_survey_client\BRIEFING.md` — Persistent working memory
- `c:\Projects\FreeExile\.agents\teamwork\explorer_survey_client\progress.md` — Progress tracking & liveness heartbeat
- `c:\Projects\FreeExile\.agents\teamwork\explorer_survey_client\report.md` — Comprehensive Client Map Architecture Survey Report
- `c:\Projects\FreeExile\.agents\teamwork\explorer_survey_client\handoff.md` — 5-Component Handoff Report