{"abstract":"Ordinary repeat wraps instead of reversing every alternate texture copy.","category":"Raster memory layout","checks":5,"contract":"Mirror-repeat integer texel indices with duplicated edge texels and period twice the positive texture size.","contract_signature":"coordinate, size","evaluation_group":"xg-texture-mirror-repeat-period","failed_approach":"Edge clamping never traverses reflected texels beyond the texture.","family":"xg-texture-mirror-repeat-period","id":"FA-10771","implementations":{"attempt":{"sha256":"d4dc2ceddd1c6bdd817f5d22eeb7847689cd279bfce6ff0398f5f6cabf7e5735","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(coordinate, size):\n    return min(size-1,max(0,coordinate))\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve(*(4, 4)), 3)\ncheck('fixture 2', solve(*(5, 4)), 2)\ncheck('fixture 3', solve(*(-1, 4)), 0)\ncheck('fixture 4', solve(*(8, 4)), 0)\ncheck('fixture 5', solve(*(2, 4)), 2)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"10ffe12e6cc957962875000d5825b4a9859a130b584bf4a453775abd6cd69e88","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(coordinate, size):\n    return coordinate%size\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve(*(4, 4)), 3)\ncheck('fixture 2', solve(*(5, 4)), 2)\ncheck('fixture 3', solve(*(-1, 4)), 0)\ncheck('fixture 4', solve(*(8, 4)), 0)\ncheck('fixture 5', solve(*(2, 4)), 2)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":" This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"xg-texture-mirror-repeat-period","generated_at":"2026-09-29T14:38:41.970420+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A deterministic software graphics stage with explicit channel and coordinate conventions; no hardware, device profile or API behavior is inferred.","root_cause":"Ordinary repeat wraps instead of reversing every alternate texture copy.","sha256":"fbb0b943d94a20bced65cd3596da0bf420da63633f1f2e85ce7661c387b1e4f4","title":"Texture mirror repeat period · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":40.051,"exit_code":1,"observations":[{"actual":3,"check":"fixture 1","expected":3,"passed":true},{"actual":3,"check":"fixture 2","expected":2,"passed":false},{"actual":0,"check":"fixture 3","expected":0,"passed":true},{"actual":3,"check":"fixture 4","expected":0,"passed":false},{"actual":2,"check":"fixture 5","expected":2,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": 3, \"expected\": 3, \"passed\": true}, {\"check\": \"fixture 2\", \"actual\": 3, \"expected\": 2, \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": 3, \"expected\": 0, \"passed\": false}, {\"check\": \"fixture 5\", \"actual\": 2, \"expected\": 2, \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":38.021,"exit_code":1,"observations":[{"actual":0,"check":"fixture 1","expected":3,"passed":false},{"actual":1,"check":"fixture 2","expected":2,"passed":false},{"actual":3,"check":"fixture 3","expected":0,"passed":false},{"actual":0,"check":"fixture 4","expected":0,"passed":true},{"actual":2,"check":"fixture 5","expected":2,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": 0, \"expected\": 3, \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": 1, \"expected\": 2, \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": 3, \"expected\": 0, \"passed\": false}, {\"check\": \"fixture 4\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"fixture 5\", \"actual\": 2, \"expected\": 2, \"passed\": true}], \"passed\": false}\n"}},"member_only":{"stages":["fixed"],"fields":["implementations.fixed","verification.fixed","harness","repair"],"note":"The verified repair, its recorded checks, the repair description, and the scoring harness are available to members."}}