proto: liminal looks - pool rooms, backrooms grid, staircase to nowhere, terraced hills (L161)

Stamp vocabulary v7 (opt-in fillBox, carveBox, fillSteps; carveArch reused); flat-field liminal stamp fixtures; capsule
walk audit with doorway-width gate (1.2 m control fails as expected). Clang/GCC W1/W8/W12 identical; owner canonical
hashes unchanged; fast tier 273/273. Terraced wide view not yet legible.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016dhxM43dnWvUu2B5Ph1iG1

Standalone/Source/StreamBenchmarkPipeline.h

@@ -22,6 +22,7 @@
 #include <limits>
 #include <numeric>
 #include <queue>
+#include <sstream>
 #include <string_view>
 #include <thread>
 #include <tuple>
@@ -2385,7 +2386,8 @@ namespace StandaloneStreamBenchmark
         double MovingCameraDurationSeconds=12.0,double MovingCameraDwellSeconds=5.0,
         bool bColdWorkerTimeline=false,bool bAuditPassageSourceClamp=false,
         bool bAuditPassageCarveReach=false,bool bAuditPassageTileSeams=false,
-        bool bAuditLiminalRoadWalk=false)
+        bool bAuditLiminalRoadWalk=false,
+        const std::filesystem::path& LiminalStampWalkAuditPath={})
     {
         using Clock=std::chrono::steady_clock;
         const std::clock_t ColdCpuOrigin=std::clock();
@@ -2555,7 +2557,8 @@ namespace StandaloneStreamBenchmark
             ||bAuditOreVeinYield||bAuditLandmarkReachability||bAuditStrateTransitions
             ||bAuditResolvedLayoutPassages||bAuditResolvedLayoutBoundaries
             ||bAuditTileShapeReadiness||bAuditBasePageEquivalence||bAuditRouteParity
-            ||bAuditPassageSourceClamp||bAuditPassageCarveReach||bAuditLiminalRoadWalk;
+            ||bAuditPassageSourceClamp||bAuditPassageCarveReach||bAuditLiminalRoadWalk
+            ||!LiminalStampWalkAuditPath.empty();
         const bool bDeferFarWorld=bIncludeFarWorld&&!bMovingCameraTrace&&!bFarWorldAudit;
         VoxelForgeCore::ShapeBuildRequest ShapeRequest;
         ShapeRequest.minVoxel={FineMin.X,FineMin.Y,FineMin.Z};
@@ -2821,7 +2824,8 @@ namespace StandaloneStreamBenchmark
             Streamer.Stop();
             return passed?0:11;
         }
-        if(bAuditResolvedLayoutPassages||bAuditLiminalRoadWalk)
+        if(bAuditResolvedLayoutPassages||bAuditLiminalRoadWalk
+            ||!LiminalStampWalkAuditPath.empty())
         {
             if(ResolvedLayout==nullptr||!CoreSnapshot.resolvedLayout())
             {Streamer.Stop();std::fprintf(stderr,"[ResolvedWalkAudit] missing resolved-layout snapshot\n");return 2;}
@@ -3230,6 +3234,82 @@ namespace StandaloneStreamBenchmark
                 }
                 return passed;
             };
+            if(!LiminalStampWalkAuditPath.empty())
+            {
+                struct FDoorwayWidthGate
+                {
+                    std::string prefix;
+                    std::uint32_t widthAxis=0;
+                    double minimumWidthMetres=0.0;
+                };
+                std::ifstream auditFile(LiminalStampWalkAuditPath);
+                std::vector<std::array<double,3>> walkPath;
+                std::vector<FDoorwayWidthGate> doorwayGates;
+                bool inputValid=static_cast<bool>(auditFile);
+                std::string line;
+                while(inputValid&&std::getline(auditFile,line))
+                {
+                    if(line.empty()||line[0]=='#')continue;
+                    std::istringstream fields(line);
+                    char record=0;fields>>record;
+                    if(record=='P')
+                    {
+                        std::array<double,3> point{};
+                        fields>>point[0]>>point[1]>>point[2];
+                        inputValid=inputValid&&static_cast<bool>(fields)
+                            &&std::isfinite(point[0])&&std::isfinite(point[1])
+                            &&std::isfinite(point[2]);
+                        if(inputValid)
+                            walkPath.push_back({point[0]/coreMetres,
+                                point[1]/coreMetres,point[2]/coreMetres});
+                    }
+                    else if(record=='D')
+                    {
+                        FDoorwayWidthGate gate;
+                        fields>>gate.prefix>>gate.widthAxis>>gate.minimumWidthMetres;
+                        inputValid=inputValid&&static_cast<bool>(fields)
+                            &&!gate.prefix.empty()&&gate.widthAxis<2
+                            &&std::isfinite(gate.minimumWidthMetres)
+                            &&gate.minimumWidthMetres>=1.5;
+                        if(inputValid)doorwayGates.push_back(std::move(gate));
+                    }
+                    else inputValid=false;
+                }
+                std::uint64_t doorwayCount=0;
+                double narrowestDoorway=std::numeric_limits<double>::infinity();
+                bool doorwayWidthsPass=inputValid;
+                for(const auto& gate:doorwayGates)
+                {
+                    std::uint64_t found=0;
+                    for(const auto& stamp:ResolvedLayout->stamps)
+                    {
+                        if(!stamp.stableId.starts_with(gate.prefix))continue;
+                        ++found;++doorwayCount;
+                        const double width=2.0*stamp.halfExtentsMicrometres[gate.widthAxis]/1.0e6;
+                        narrowestDoorway=std::min(narrowestDoorway,width);
+                        if(width+1.0e-9<gate.minimumWidthMetres)doorwayWidthsPass=false;
+                    }
+                    doorwayWidthsPass=doorwayWidthsPass&&found>0;
+                }
+                if(doorwayCount==0)narrowestDoorway=0.0;
+                const FWalkAudit walkAudit=inputValid&&walkPath.size()>=2
+                    ?auditPlayerPath(Shape,walkPath,0.125,0.125,1.125,3,0.45):FWalkAudit{};
+                const bool passed=inputValid&&doorwayWidthsPass&&walkAudit.passed;
+                std::printf("[LiminalStampWalkAudit] path_points=%zu stations=%llu capsule_samples=%llu "
+                    "blocked=%llu support_samples=%llu unsupported=%llu grade_failures=%llu "
+                    "doorways=%llu narrowest_doorway_m=%.3f minimum_doorway_m=1.500 "
+                    "status=%s\n",walkPath.size(),
+                    static_cast<unsigned long long>(walkAudit.centers),
+                    static_cast<unsigned long long>(walkAudit.capsuleSamples),
+                    static_cast<unsigned long long>(walkAudit.blocked),
+                    static_cast<unsigned long long>(walkAudit.supportSamples),
+                    static_cast<unsigned long long>(walkAudit.unsupported),
+                    static_cast<unsigned long long>(walkAudit.gradeFailures),
+                    static_cast<unsigned long long>(doorwayCount),narrowestDoorway,
+                    passed?"PASS":"FAIL");
+                Streamer.Stop();
+                return passed?0:14;
+            }
             if(bAuditLiminalRoadWalk&&!bAuditResolvedLayoutPassages)
             {
                 const bool passed=auditLiminalRoadWalk(true);