From a20796cf9baf9bdf11190ff452cef12888c68c72 Mon Sep 17 00:00:00 2001
From: Davide Cappellini <signorsasso@gmail.com>
Date: Thu, 17 Sep 2026 08:38:37 +0200
Subject: [PATCH] feat(reservoir): warm-start grid with analytical lead values

Pre-populate all LeadGrid cells with arcsin(vPerp/bulletSpeed) so the
grid starts warm instead of cold, avoiding the early-round 0-data
fallback to -999 (no-lead) firing.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
---
 SNNBot_garage/src/reservoir.nim | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/SNNBot_garage/src/reservoir.nim b/SNNBot_garage/src/reservoir.nim
index 34377d0..bf6ae4e 100644
--- a/SNNBot_garage/src/reservoir.nim
+++ b/SNNBot_garage/src/reservoir.nim
@@ -16,8 +16,18 @@ type
   LeadGrid* = object
     cells: array[VPERP_BINS * DIST_BINS, GridCell]  # 17 × 8 = 136 cells
 
+const BULLET_SPEED = 14.0  # power 2 bullet speed in pixels/tick
+
 proc initLeadGrid*(): LeadGrid =
-  result = LeadGrid()
+  for vBin in 0..<VPERP_BINS:
+    for dBin in 0..<DIST_BINS:
+      let vPerp = float(vBin) - 8.0
+      let sinVal = clamp(vPerp / BULLET_SPEED, -1.0, 1.0)
+      let offsetRad = arcsin(sinVal)
+      let idx = vBin * DIST_BINS + dBin
+      result.cells[idx].sumSin = sin(offsetRad)
+      result.cells[idx].sumCos = cos(offsetRad)
+      result.cells[idx].count = 1
 
 proc cellIndex(vPerp: float, distance: float): int {.inline.} =
   let vBin = clamp(int(vPerp + 8.5), 0, VPERP_BINS - 1)