[55]: Added snapping of drawing to other camps and fireroads

SETTINGS.ts

@@ -10,10 +10,29 @@ export const MAX_CLUSTER_SIZE: number = 1250;
 export const MAX_POWER_NEED: number = 8000;
 export const MAX_POINTS_BEFORE_WARNING: number = 10;
 export const FIRE_BUFFER_IN_METER: number = 5;
+/** Max snap distance when snapping to fireroads (m). */
+export const SNAP_DISTANCE_METERS: number = 2;
+/** Max snap distance when snapping to other camps (m) — tighter than fireroads. */
+export const CAMP_SNAP_DISTANCE_METERS: number = 1;
+/** Fireroad centerline buffer used for placement rules (m). */
+export const FIREROAD_CLEARANCE_METERS: number = 2.5;
+/** Extra buffer for snap targets so vertices land outside the clearance polygon (m). */
+export const FIREROAD_SNAP_OUTSET_METERS: number = 0.1;
+/** Shrink zone polygons before clearance overlap tests (fireroad, slope, etc.) (m). */
+export const SNAP_EDGE_TOLERANCE_METERS: number = 1;
+/** Offset outward from a camp edge when snapping (m). */
+export const CAMP_SNAP_GAP_METERS: number = 0.2;
+/**
+ * Camp-vs-camp: any shared area above this (m²) is invalid. Kept tiny for float noise only.
+ * Touching without overlapping has ~0 m² intersection and is allowed.
+ */
+export const MIN_CAMP_AREA_OVERLAP_SQM: number = 0.05;
+/** Min overlap (m²) for zone rules (fireroad buffers, etc.), not camp-vs-camp. */
+export const MIN_CAMP_OVERLAP_AREA_SQM: number = 1;
 
 export const TOTAL_MEMBERSHIPS_SOLD = 5432; // 2026, this is used for the stats page.
 export const SOUND_GUIDE_URL = 'https://docs.google.com/document/d/1aDBv3UWOxngdjWd_z4N34Wcm7r7GvD-gINGwQIr4ti8';
 export const POWER_GRID_GEOJSON_URL = 'https://bl.skookum.cc/api/bl26/v/default/power_grid';
 
 export const HAS_SEEN_PLACEMENT_WELCOME_COOKIE_KEY = 'hasSeenPlacementWelcome';
-export const HAS_SEEN_EDITOR_INSTRUCTIONS_COOKIE_KEY = 'hasSeenEditorInstructions';
+export const HAS_SEEN_EDITOR_INSTRUCTIONS_COOKIE_KEY = 'hasSeenEditorInstructions';

public/drawers/guide-usage.html

@@ -1,7 +1,10 @@
 <h2>Your Placement Tools<img title="" src="guide/tool.png" alt="Quick help" /></h2>
 <ol start="1">
     <li>Click the "Edit" button in the lower left</li>
-    <li>Start drawing a shape and close it by clicking on the first point</li>
+    <li>
+        Start drawing a shape and close it by clicking on the first point. While drawing, points will snap to a target
+        within 2m. Hold down ALT while drawing to disable snapping.
+    </li>
     <li>
         A box will pop up asking for your camp's information. Fill in all fields, including power needs, sound levels,
         and your contact information (so people can collaborate with you!)