From 7b479f535727caf5ca28a08618d86e8bbff4b8bf Mon Sep 17 00:00:00 2001
From: Matiq <kokagishi@proton.me>
Date: Sun, 30 Aug 2026 18:07:15 +0300
Subject: [PATCH] B1/B2: ACC table double-deref 5407c8 + chain_9_19_sim
 op-by-op (BLOCKMAP 620-644)

---
 scripts/cascade_sim.py | 39 +++++++++++++++++++++++++++++++++++++++
 scripts/rendersnap2.py | 19 +++++++++++++++++++
 2 files changed, 58 insertions(+)

diff --git a/scripts/cascade_sim.py b/scripts/cascade_sim.py
index 047c873..d2be623 100644
--- a/scripts/cascade_sim.py
+++ b/scripts/cascade_sim.py
@@ -62,6 +62,45 @@ def k_div_exact(a, b):
     return np.asarray(b, dtype=np.float64) / np.asarray(a, dtype=np.float64)
 
 
+def chain_9_19_sim(bands, tmp6f8, accVec, warp, att, rel, nbin=None):
+    """CHAIN 9-19 BLOCKMAP:620-644 op-by-op (python структурный прокси).
+    bands: log-domain bands_curve_i (size nbin), tmp6f8: f6f8, accVec: ACC_i
+    warp: kWarp@5406a8, att@5406c8 rel@5406e8 — все 2049.
+    Возвращает bands mutated (log domain после IIR, перед FIR)."""
+    if nbin is None:
+        nbin = len(bands)
+    bands = np.asarray(bands, dtype=np.float64)
+    tmp6f8 = np.asarray(tmp6f8, dtype=np.float64)
+    accVec = np.asarray(accVec, dtype=np.float64)
+    # 9a zero already (vec698 irrelevant), 9b: tmp6f8 += 0.8 (p=1.0 *0.8)
+    # 9c DIVIDE dst=bands A=bands B=tmp6f8+0.8? Actually B=tmp6f8, but step 9b already added 0.8
+    # BLOCKMAP 24mm5: bands = tmp6f8 / bands (divide B/A)
+    # Use k_div_exact
+    b = tmp6f8 + 0.8  # proxy for step 9b effect (when tmp6f8 initially 0, b=0.8)
+    # If tmp6f8 already has data, 9b is additive 0.8, so b = tmp6f8 +0.8
+    # For calibration where tmp6f8 is 0, this yields 0.8/bands
+    bands = k_div_exact(np.maximum(bands, 1e-30), b)
+    # 10 dc40: tmp6f8 = bands - ACC
+    tmp6f8 = bands - accVec
+    # 11 FMA ATT/REL half-split
+    # true triples 12B re/im/coef, scalar proxy: upper half ATT, lower REL
+    for i in range(nbin):
+        if i < nbin // 2:
+            tmp6f8[i] += att[i] * accVec[i]
+        else:
+            tmp6f8[i] += rel[i] * accVec[i]
+    # 14 EXP#1 + -1 (order fixed 24mm2)
+    bands = k_exp_exact(bands) - 1.0
+    # 15 array-mul X*track (track is external, warp mul is step16)
+    # 16 *kWarp + LOG#2
+    bands = bands * warp
+    bands = np.log(np.maximum(bands, 1e-30))
+    # 16b IIR4x2 bidir log-domain base 0x340510 — proxy via kIIR_A1/B1
+    # keep as identity for now (real IIR is mild 0.003-0.19 per 24cc)
+    # FIR will be applied externally via fir_kernel
+    return bands, tmp6f8
+
+
 # ------------------------------------------------------------ данные -----
 def load_tract(path):
     """tract_*.txt: k am res lvl_raw band_level prewarp w"""
diff --git a/scripts/rendersnap2.py b/scripts/rendersnap2.py
index d454cd9..7a24770 100644
--- a/scripts/rendersnap2.py
+++ b/scripts/rendersnap2.py
@@ -176,6 +176,25 @@ def main():
                             store['lut_G'] = struct.unpack('<f', fb4[12:16])[0]
                             store['lut_mode'] = fb4[16]
                 for off in SLOTS[1:]:
+                    if off == 0x5407c8:
+                        # ACC is table of pointers per-band [5407c8 + i*8] -> buf 2049 f32 each
+                        for bi in range(4):
+                            q = rd(ctx + off + 8*bi, 8)
+                            if not q: continue
+                            ptr = struct.unpack('<Q', q)[0]
+                            if ptr < 0x10000: continue
+                            ab = rd(ptr, 2049 * 4)
+                            if ab:
+                                store[hex(off) + f"_{bi}"] = np.frombuffer(ab, dtype='<f4').astype(np.float32)
+                        # also store raw table pointer for debug
+                        q = rd(ctx + off, 8)
+                        if q:
+                            ptr = struct.unpack('<Q', q)[0]
+                            if ptr >= 0x10000:
+                                ab = rd(ptr, NARR * 4)
+                                if ab:
+                                    store[hex(off)] = np.frombuffer(ab, dtype='<f4').astype(np.float32)
+                        continue
                     q = rd(ctx + off, 8)
                     if not q:
                         continue