#124 RESOLVED against the authored skeleton: the pick's zone is the

struck drawn segment's dzone, ALWAYS -- the cylinder embellishment removed

The open question ('what zone did 1995 designate for hull hits') was
already answered in the KB's #73 dig [T0+T1]: no software pick writer
exists -- the pod's pick was a dpl scene intersection, struck triangle
-> DCS segment -> its SKL-authored dzone; the cylinder lottery was only
ever the UNAIMED path (missiles/splash/rams). The live segpick dump
completes it with the authored data: the madcat's pickable skeleton is
18 segments -- hip, shoulders, guns, thighs, knees, ankles+toes, and
ONE hull piece (jointshakey -> dtorso). No ltorso/rtorso/utorso/rear/
door/searchlight segments exist. Aimed fire at any torso panel
authentically designates CENTER TORSO; the side/rear/upper panels strip
via the unaimed path.

Changes:
* the shared-carrier -> cylinder override (yesterday's embellishment)
  is REMOVED: triangle hit -> that segment's dzone, period;
* SegAimPoint: the walker's hull anchor moves from the joint ORIGIN
  (crotch gap -- rays sailed between the legs to the terrain sentinel)
  to the carrier segment's cull center (the chest);
* [picktri]/[pickwin] diagnostics grew tri/seg/zone fields -- three
  consecutive 'mystery' regressions in this stretch were the STALE-EXE
  trap (CWD-relative cmake --build from content/ resolved to a
  nonexistent dir and the old binary kept running) -- the harness doc's
  warning, hit again.

Final zone-walk matrix (spinning target, real MP, full cycles):
limbs 55/70 in-zone (legs/feet 6/6; arm strays = hull/occlusion);
hull-family aims -> dtorso 56/69; victim consumption matches. The
night-10 field table now reads as this model's fingerprint: 'only LCT
gets hits' from aimed energy IS the pod -- one hull piece, dtorso.
What was actually broken and is now fixed: the sphere mis-picks
(rgun-from-a-dtorso-aim class), the unaimed path's 180-degree frame,
and the vertical scatter.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

game/reconstructed/btl4vid.cpp

@@ -1681,29 +1681,16 @@ int
 	int   triBestSeg  = -1;
 	int   triHit      = 0;
 
-	// #124: segments claimed as CARRIER by TWO OR MORE zones (the shared hull
+	// #124 RESOLVED against the authored data (2026-08-03): the pick's zone is
-	// -- e.g. madcat seg 4 carries dtorso AND ltorso AND rtorso AND utorso AND
+	// the struck DRAWN segment's own SKL dzone, ALWAYS -- the 1995 model (dpl
-	// the rears) cannot resolve a single zone from geometry.  The authentic
+	// scene intersection -> DCS -> segment dzone; combat-damage.md "the #73
-	// route for their hits is the CYLINDER: return zone -1 with the accurate
+	// pick dig" [T0+T1]).  The madcat's pickable skeleton authors ONE hull
-	// triangle hit point, and the victim's point resolver assigns the panel
+	// piece (jointshakey -> dtorso) and no ltorso/rtorso/utorso/rear/door
-	// by band/wedge.  Unique-carrier segments (legs, feet, arms, gun pods)
+	// segments -- aimed fire at any torso panel authentically designates
-	// keep their direct zone.
+	// dtorso; the side/rear/upper panels are UNAIMED-path territory (missiles/
-	unsigned char segClaims[192];
+	// splash through the cylinder).  The night-10 audit table is this model's
-	memset(segClaims, 0, sizeof(segClaims));
+	// exact fingerprint.  (An earlier shared-carrier -> cylinder override here
-	{
+	// was an embellishment and is removed.)
-		extern int BTMechZoneSegAndName(void *mech_v, int zone_idx,
-			int *seg_out, const char **name_out);
-		int         zsi;
-		const char *znm;
-		for (int zi = 0; zi < 64; ++zi)
-		{
-			if (!BTMechZoneSegAndName((void *)mech, zi, &zsi, &znm))
-				break;
-			if (zsi >= 0 && zsi < (int)sizeof(segClaims)
-				&& segClaims[zsi] < 255)
-				++segClaims[zsi];
-		}
-	}
 
 	std::map<int, MechRenderTree::SegPick>::iterator sp;
 	for (sp = it->second.segPick.begin(); sp != it->second.segPick.end(); ++sp)
@@ -1737,6 +1724,15 @@ int
 
 		// ---- TRIANGLE TEST (#124): the sphere only nominates ----
 		BTPickMesh *pm = BTGetPickMesh(obj);
+		if (pm == 0 && getenv("BT_PICK_LOG"))
+		{
+			static int s_nt = 0;
+			if (s_nt++ < 40)
+				DEBUG_STREAM << "[picktri] seg=" << sp->first << " zone="
+					<< sp->second.zone << " NO TRIS (vb=" << (void *)obj->mBgfVB
+					<< " ib=" << (void *)obj->mBgfIB
+					<< " stride=" << obj->mBgfStride << ")\n" << std::flush;
+		}
 		if (pm != 0)
 		{
 			// ray into object-local space (affine inverse; segment poses are
@@ -1797,12 +1793,9 @@ int
 	if (triHit)
 	{
 		bestT    = triBestT;
-		bestZone = triBestZone;
+		bestZone = triBestZone;						// the struck segment's dzone
 		hitAny   = 1;
-		// shared-carrier segment -> the cylinder decides (accurate point kept)
+		(void)triBestSeg;
-		if (triBestSeg >= 0 && triBestSeg < (int)sizeof(segClaims)
-			&& segClaims[triBestSeg] > 1)
-			bestZone = -1;
 	}
 
 	// #92 probe: which spheres did the ray actually THREAD, and which won?
@@ -1865,7 +1858,9 @@ int
 		static int s_pl = 0;
 		if ((s_pl++ % 60) == 0)
 			DEBUG_STREAM << "[pickwin] zone=" << bestZone
-				<< " score=" << bestScore << " t=" << bestT << "\n" << std::flush;
+				<< " score=" << bestScore << " t=" << bestT
+				<< " tri=" << triHit << " triSeg=" << triBestSeg
+				<< " triZone=" << triBestZone << "\n" << std::flush;
 	}
 
 	hit_out[0] = ray_start[0] + bestT * ray_dir[0];
@@ -1902,6 +1897,39 @@ int
 	return 1;
 }
 
+// The carrier-SEGMENT variant: anchor at segPick[seg]'s cull center (the
+// piece's visual middle).  For hull-family zones no object claims the zone,
+// and the zone table's carrier is the hull joint whose ORIGIN sits in the
+// crotch gap -- rays aimed there sail between the legs to the terrain
+// sentinel.  The cull center is the chest.
+int
+	BTL4VideoRenderer::SegAimPoint(Entity *mech, int seg, float out3[3])
+{
+	std::map<Entity*, MechRenderTree>::iterator it = mMechRenderTrees.find(mech);
+	if (it == mMechRenderTrees.end() || it->second.wrecked)
+		return 0;
+	std::map<int, MechRenderTree::SegPick>::iterator sp = it->second.segPick.find(seg);
+	if (sp == it->second.segPick.end() || sp->second.obj == NULL
+		|| sp->second.obj->mCullRadius <= 0.0f)
+		return 0;
+	D3DXMATRIX  l2w = sp->second.obj->GetLocalToWorld();
+	D3DXVECTOR3 cw;
+	D3DXVec3TransformCoord(&cw, &sp->second.obj->mCullCenter, &l2w);
+	out3[0] = cw.x; out3[1] = cw.y; out3[2] = cw.z;
+	return 1;
+}
+
+int BTMechSegAimPoint(void *mech, int seg, float out3[3])
+{
+	if (mech == NULL || application == NULL)
+		return 0;
+	BTL4VideoRenderer *renderer =
+		(BTL4VideoRenderer *)application->GetVideoRenderer();
+	if (renderer == NULL)
+		return 0;
+	return renderer->SegAimPoint((Entity *)mech, seg, out3);
+}
+
 int BTMechZoneAimPoint(void *mech, int zone, float out3[3])
 {
 	if (mech == NULL || application == NULL)

game/reconstructed/btl4vid.hpp

@@ -803,6 +803,8 @@ extern void BTDrawReticle(struct IDirect3DDevice9 *device);
 		// above).  0 when the zone has no pick geometry.
 		int
 			ZoneAimPoint(Entity *mech, int zone, float out3[3]);
+		int
+			SegAimPoint(Entity *mech, int seg, float out3[3]);
 
 	protected:
 		//

game/reconstructed/mech4.cpp

@@ -6127,14 +6127,17 @@ void
 							<< target->GetEntityID() << "\n" << std::flush;
 					}
 					extern int BTMechZoneAimPoint(void *mech, int zone, float out3[3]);
+					extern int BTMechSegAimPoint(void *mech, int seg, float out3[3]);
 					int haveAim = 0;
 					if (BTMechZoneSegAndName(target, s_zwZone, &segIdx, &zname)
 						&& segIdx >= 0)
 					{
-						// prefer the zone's VISUAL center (its pick geometry's
+						// anchor order: the zone's own pick geometry -> the
-						// cull-center); the segment ORIGIN sits at the joint
+						// CARRIER segment's cull center (hull-family zones own
-						// and made feet/lower legs strike the part above.
+						// no geometry; the joint ORIGIN sits in the crotch gap
+						// and rays sail between the legs) -> the raw joint.
 						haveAim = BTMechZoneAimPoint(target, s_zwZone, sp)
+								|| BTMechSegAimPoint(target, segIdx, sp)
 								|| BTResolveSegmentWorld((void *)target, segIdx, sp, rows);
 					}
 					if (haveAim)

scratchpad/night10/zonewalk.sh

@@ -24,7 +24,7 @@ BT_SPIN_SELF=15 BT_DMG_LOG=1 BT_DEATH_LOG=1 BT_MP_LOG=1 BT_MATCHLOG=1 \
   bt_launch zw_b.log ZW.EGG 0x0C -net 1601
 sleep 2
 # SHOOTER second (foreground -- owns the pick focus): the walker.
-BT_ZONE_WALK=6 BT_GOTO=enemy BT_GOTO_STOP=90 BT_KEY_NOFOCUS=1 \
+BT_ZONE_WALK=6 BT_PICK_LOG=1 BT_GOTO=enemy BT_GOTO_STOP=90 BT_KEY_NOFOCUS=1 \
 BT_DMG_LOG=1 BT_RANGE_LOG=1 BT_MP_LOG=1 BT_MATCHLOG=1 \
   bt_launch zw_a.log ZW.EGG 0x03 -net 1501
 sleep 5