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FA-86741 / Procedural level generation constraints / Open access

Rotated prefab stamping: Transparent cells overwrite terrain · case 01

Prefab holes erase existing walls.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

Floor, not space, is treated as transparent.

VERIFIED REPAIR

Restore `if t == ' ':` at the transparency step.

Unsuccessful approach: Also treating floor as transparent stops prefabs from carving floors.

Case contract

The prefab (rows of chars, ' ' transparent) is rotated clockwise rot times (rot taken mod 4, negative allowed) and stamped with its top-left at column ox, row oy. If any non-transparent tile would land out of bounds or on a locked 'X' tile, the stamp is rejected and the original grid returned with False; otherwise the new grid with True.

Why this case matters

Procedural generators silently emit unplayable or unfair levels when a single constraint check uses the wrong boundary, axis, neighborhood or update order; the defect is visible in exact generated geometry.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(grid, prefab, ox, oy, rot):
    p = [list(row) for row in prefab]
    for _ in range(rot % 4):
        p = [list(row) for row in zip(*p[::-1])]
    g = [list(row) for row in grid]
    for r, line in enumerate(p):
        for c, t in enumerate(line):
            if t == '.':
                continue
            y, x = oy + r, ox + c
            if not (0 <= y < len(g) and 0 <= x < len(g[0])) or g[y][x] == 'X':
                return [grid, False]
            g[y][x] = t
    return [[''.join(row) for row in g], True]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[('transparent overhang #1', [['..', '..'], [' #', ' #'], -1, 0, 0], [['#.', '#.'], True]),
  ('regression transparency #1',
   [['...', '#..', 'X..', '...', '#X.', '..X'], ['.D.', '#.D'], 0, 0, -1],
   [['...', '#..', 'X..', '...', '#X.', '..X'], False]),
  ('fault site transparency #1', [['.#.', '#..'], ['  ', 'DD', '#.'], 0, -1, 4], [['DD.', '#..'], True]),
  ('regression transparency #2',
   [['##.', '..#', '#..', '.X.', '.#X', '#..'], ['.', 'D', '.'], 1, 1, 6],
   [['##.', '..#', '#..', '.X.', '.#X', '#..'], False]),
  ('partial repair boundary #1',
   [['......', '...X..', 'X.#...'], [' ', '.', ' '], -1, -1, 4],
   [['......', '...X..', 'X.#...'], False]),
  ('quarter turn #1', [['....', '....'], ['#D'], 0, 0, 1], [['#...', 'D...'], True]),
  ('counter-clockwise turn #1', [['...', '...'], ['#.', '..'], 0, 0, -1], [['...', '#..'], True]),
  ('control #1', [['.#...#', '.#.#..'], ['  ', '# '], 1, -1, 6], [['.#...#', '.#.#..'], False])],
 [('transparent overhang #1', [['..', '..'], [' #', ' #'], -1, 0, 0], [['#.', '#.'], True]),
  ('fault site transparency #1', [['.#.', '#..'], ['  ', 'DD', '#.'], 0, -1, 4], [['DD.', '#..'], True]),
  ('fault site transparency #2',
   [['..#X.', '.....', '.....', '.XX#.'], ['##D', '#. ', '.# '], 0, 0, 0],
   [['##DX.', '#....', '.#...', '.XX#.'], True]),
  ('partial repair boundary #1',
   [['......', '...X..', 'X.#...'], [' ', '.', ' '], -1, -1, 4],
   [['......', '...X..', 'X.#...'], False]),
  ('regression transparency #1',
   [['.....', 'X..X#', 'X.X.X'], ['. .'], 1, 1, 2],
   [['.....', 'X..X#', 'X.X.X'], False]),
  ('quarter turn #1', [['....', '....'], ['#D'], 0, 0, 1], [['#...', 'D...'], True]),
  ('counter-clockwise turn #1', [['...', '...'], ['#.', '..'], 0, 0, -1], [['...', '#..'], True]),
  ('control #1', [['.#...#', '.#.#..'], ['  ', '# '], 1, -1, 6], [['.#...#', '.#.#..'], False])],
 [('transparent overhang #1', [['..', '..'], [' #', ' #'], -1, 0, 0], [['#.', '#.'], True]),
  ('fault site transparency #1',
   [['...#..', '.#....', '#.....'], ['#.', ' .', '#D'], 2, 0, 5],
   [['..###.', '.#D...', '#.....'], True]),
  ('fault site transparency #2',
   [['#.#', '#..', '#..', '#.X', 'X#.'], [' '], 1, 4, 3],
   [['#.#', '#..', '#..', '#.X', 'X#.'], True]),
  ('regression transparency #1',
   [['..#.X.', '......', '.#..#.', 'XX.#.#', 'X..#.X'], ['  ', ' .', 'D.'], 4, 0, 2],
   [['..#.X.', '......', '.#..#.', 'XX.#.#', 'X..#.X'], False]),
  ('regression transparency #2',
   [['.....#', '#.#..X', 'X.....', '..#XX.', '.#..X.', '...#X.'], ['D', '.'], 2, 3, -1],
   [['.....#', '#.#..X', 'X.....', '..#XX.', '.#..X.', '...#X.'], False]),
  ('quarter turn #1', [['....', '....'], ['#D'], 0, 0, 1], [['#...', 'D...'], True]),
  ('counter-clockwise turn #1', [['...', '...'], ['#.', '..'], 0, 0, -1], [['...', '#..'], True]),
  ('control #1', [['.#...#', '.#.#..'], ['  ', '# '], 1, -1, 6], [['.#...#', '.#.#..'], False])],
 [('transparent overhang #1', [['..', '..'], [' #', ' #'], -1, 0, 0], [['#.', '#.'], True]),
  ('fault site transparency #1',
   [['..#', '...', '...', '##.'], [' #', 'D#'], 1, 2, -3],
   [['..#', '...', '.D.', '###'], True]),
  ('regression transparency #1',
   [['##.', '..#', '#..', '.X.', '.#X', '#..'], ['.', 'D', '.'], 1, 1, 6],
   [['##.', '..#', '#..', '.X.', '.#X', '#..'], False]),
  ('partial repair boundary #1',
   [['.X.', '...', 'X..', '..X', '..#'], ['D.', '. '], 0, -1, 3],
   [['.X.', '...', 'X..', '..X', '..#'], False]),
  ('regression transparency #2',
   [['#...#.', '.##X..', '...X#.', '..XX..', '..#X.#'], ['.', '.'], 1, 1, -1],
   [['#...#.', '...X..', '...X#.', '..XX..', '..#X.#'], True]),
  ('quarter turn #1', [['....', '....'], ['#D'], 0, 0, 1], [['#...', 'D...'], True]),
  ('counter-clockwise turn #1', [['...', '...'], ['#.', '..'], 0, 0, -1], [['...', '#..'], True]),
  ('control #1',
   [['#X', '..', '..', '#.', '#.'], [' D', '.#', '.#'], -1, 2, 3],
   [['#X', '..', '..', '#.', '#.'], False])],
 [('transparent overhang #1', [['..', '..'], [' #', ' #'], -1, 0, 0], [['#.', '#.'], True]),
  ('regression transparency #1',
   [['.....', 'X..X#', 'X.X.X'], ['. .'], 1, 1, 2],
   [['.....', 'X..X#', 'X.X.X'], False]),
  ('regression transparency #2',
   [['..#.X.', '......', '.#..#.', 'XX.#.#', 'X..#.X'], ['  ', ' .', 'D.'], 4, 0, 2],
   [['..#.X.', '......', '.#..#.', 'XX.#.#', 'X..#.X'], False]),
  ('regression transparency #3',
   [['...', '...', '...', 'X#.', 'X#.', '...'], ['.', '.', ' '], 1, 3, -1],
   [['...', '...', '...', 'X..', 'X#.', '...'], True]),
  ('partial repair boundary #1',
   [['..', 'X.', '.X', '.#', '.#', '#.'], ['. '], -1, 3, 1],
   [['..', 'X.', '.X', '.#', '.#', '#.'], False]),
  ('quarter turn #1', [['....', '....'], ['#D'], 0, 0, 1], [['#...', 'D...'], True]),
  ('counter-clockwise turn #1', [['...', '...'], ['#.', '..'], 0, 0, -1], [['...', '#..'], True]),
  ('control #1',
   [['XX', 'X.', '..', '..', '..'], ['D', 'D', ' '], 0, 4, -3],
   [['XX', 'X.', '..', '..', '..'], False])]]
for label, args, expected in cases[N-1]:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
transparent overhang #1[['..', '..'], False][['#.', '#.'], True]Failed
regression transparency #1[['.D.', 'D..', 'X#.', '...', '#X.', '..X'], True][['...', '#..', 'X..', '...', '#X.', '..X'], False]Failed
fault site transparency #1[['.#.', '#..'], False][['DD.', '#..'], True]Failed
regression transparency #2[['##.', '..#', '#D.', '.X.', '.#X', '#..'], True][['##.', '..#', '#..', '.X.', '.#X', '#..'], False]Failed
partial repair boundary #1[['......', '...X..', 'X.#...'], False][['......', '...X..', 'X.#...'], False]Passed
quarter turn #1[['#...', 'D...'], True][['#...', 'D...'], True]Passed
counter-clockwise turn #1[['...', '#..'], True][['...', '#..'], True]Passed
control #1[['.#...#', '.#.#..'], False][['.#...#', '.#.#..'], False]Passed

SHA-256 / c99cf2efe87b6725d117cf51958db6100a121380edd1d6e162ab134f31a3de6b

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(grid, prefab, ox, oy, rot):
    p = [list(row) for row in prefab]
    for _ in range(rot % 4):
        p = [list(row) for row in zip(*p[::-1])]
    g = [list(row) for row in grid]
    for r, line in enumerate(p):
        for c, t in enumerate(line):
            if t in ' .':
                continue
            y, x = oy + r, ox + c
            if not (0 <= y < len(g) and 0 <= x < len(g[0])) or g[y][x] == 'X':
                return [grid, False]
            g[y][x] = t
    return [[''.join(row) for row in g], True]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[('transparent overhang #1', [['..', '..'], [' #', ' #'], -1, 0, 0], [['#.', '#.'], True]),
  ('regression transparency #1',
   [['...', '#..', 'X..', '...', '#X.', '..X'], ['.D.', '#.D'], 0, 0, -1],
   [['...', '#..', 'X..', '...', '#X.', '..X'], False]),
  ('fault site transparency #1', [['.#.', '#..'], ['  ', 'DD', '#.'], 0, -1, 4], [['DD.', '#..'], True]),
  ('regression transparency #2',
   [['##.', '..#', '#..', '.X.', '.#X', '#..'], ['.', 'D', '.'], 1, 1, 6],
   [['##.', '..#', '#..', '.X.', '.#X', '#..'], False]),
  ('partial repair boundary #1',
   [['......', '...X..', 'X.#...'], [' ', '.', ' '], -1, -1, 4],
   [['......', '...X..', 'X.#...'], False]),
  ('quarter turn #1', [['....', '....'], ['#D'], 0, 0, 1], [['#...', 'D...'], True]),
  ('counter-clockwise turn #1', [['...', '...'], ['#.', '..'], 0, 0, -1], [['...', '#..'], True]),
  ('control #1', [['.#...#', '.#.#..'], ['  ', '# '], 1, -1, 6], [['.#...#', '.#.#..'], False])],
 [('transparent overhang #1', [['..', '..'], [' #', ' #'], -1, 0, 0], [['#.', '#.'], True]),
  ('fault site transparency #1', [['.#.', '#..'], ['  ', 'DD', '#.'], 0, -1, 4], [['DD.', '#..'], True]),
  ('fault site transparency #2',
   [['..#X.', '.....', '.....', '.XX#.'], ['##D', '#. ', '.# '], 0, 0, 0],
   [['##DX.', '#....', '.#...', '.XX#.'], True]),
  ('partial repair boundary #1',
   [['......', '...X..', 'X.#...'], [' ', '.', ' '], -1, -1, 4],
   [['......', '...X..', 'X.#...'], False]),
  ('regression transparency #1',
   [['.....', 'X..X#', 'X.X.X'], ['. .'], 1, 1, 2],
   [['.....', 'X..X#', 'X.X.X'], False]),
  ('quarter turn #1', [['....', '....'], ['#D'], 0, 0, 1], [['#...', 'D...'], True]),
  ('counter-clockwise turn #1', [['...', '...'], ['#.', '..'], 0, 0, -1], [['...', '#..'], True]),
  ('control #1', [['.#...#', '.#.#..'], ['  ', '# '], 1, -1, 6], [['.#...#', '.#.#..'], False])],
 [('transparent overhang #1', [['..', '..'], [' #', ' #'], -1, 0, 0], [['#.', '#.'], True]),
  ('fault site transparency #1',
   [['...#..', '.#....', '#.....'], ['#.', ' .', '#D'], 2, 0, 5],
   [['..###.', '.#D...', '#.....'], True]),
  ('fault site transparency #2',
   [['#.#', '#..', '#..', '#.X', 'X#.'], [' '], 1, 4, 3],
   [['#.#', '#..', '#..', '#.X', 'X#.'], True]),
  ('regression transparency #1',
   [['..#.X.', '......', '.#..#.', 'XX.#.#', 'X..#.X'], ['  ', ' .', 'D.'], 4, 0, 2],
   [['..#.X.', '......', '.#..#.', 'XX.#.#', 'X..#.X'], False]),
  ('regression transparency #2',
   [['.....#', '#.#..X', 'X.....', '..#XX.', '.#..X.', '...#X.'], ['D', '.'], 2, 3, -1],
   [['.....#', '#.#..X', 'X.....', '..#XX.', '.#..X.', '...#X.'], False]),
  ('quarter turn #1', [['....', '....'], ['#D'], 0, 0, 1], [['#...', 'D...'], True]),
  ('counter-clockwise turn #1', [['...', '...'], ['#.', '..'], 0, 0, -1], [['...', '#..'], True]),
  ('control #1', [['.#...#', '.#.#..'], ['  ', '# '], 1, -1, 6], [['.#...#', '.#.#..'], False])],
 [('transparent overhang #1', [['..', '..'], [' #', ' #'], -1, 0, 0], [['#.', '#.'], True]),
  ('fault site transparency #1',
   [['..#', '...', '...', '##.'], [' #', 'D#'], 1, 2, -3],
   [['..#', '...', '.D.', '###'], True]),
  ('regression transparency #1',
   [['##.', '..#', '#..', '.X.', '.#X', '#..'], ['.', 'D', '.'], 1, 1, 6],
   [['##.', '..#', '#..', '.X.', '.#X', '#..'], False]),
  ('partial repair boundary #1',
   [['.X.', '...', 'X..', '..X', '..#'], ['D.', '. '], 0, -1, 3],
   [['.X.', '...', 'X..', '..X', '..#'], False]),
  ('regression transparency #2',
   [['#...#.', '.##X..', '...X#.', '..XX..', '..#X.#'], ['.', '.'], 1, 1, -1],
   [['#...#.', '...X..', '...X#.', '..XX..', '..#X.#'], True]),
  ('quarter turn #1', [['....', '....'], ['#D'], 0, 0, 1], [['#...', 'D...'], True]),
  ('counter-clockwise turn #1', [['...', '...'], ['#.', '..'], 0, 0, -1], [['...', '#..'], True]),
  ('control #1',
   [['#X', '..', '..', '#.', '#.'], [' D', '.#', '.#'], -1, 2, 3],
   [['#X', '..', '..', '#.', '#.'], False])],
 [('transparent overhang #1', [['..', '..'], [' #', ' #'], -1, 0, 0], [['#.', '#.'], True]),
  ('regression transparency #1',
   [['.....', 'X..X#', 'X.X.X'], ['. .'], 1, 1, 2],
   [['.....', 'X..X#', 'X.X.X'], False]),
  ('regression transparency #2',
   [['..#.X.', '......', '.#..#.', 'XX.#.#', 'X..#.X'], ['  ', ' .', 'D.'], 4, 0, 2],
   [['..#.X.', '......', '.#..#.', 'XX.#.#', 'X..#.X'], False]),
  ('regression transparency #3',
   [['...', '...', '...', 'X#.', 'X#.', '...'], ['.', '.', ' '], 1, 3, -1],
   [['...', '...', '...', 'X..', 'X#.', '...'], True]),
  ('partial repair boundary #1',
   [['..', 'X.', '.X', '.#', '.#', '#.'], ['. '], -1, 3, 1],
   [['..', 'X.', '.X', '.#', '.#', '#.'], False]),
  ('quarter turn #1', [['....', '....'], ['#D'], 0, 0, 1], [['#...', 'D...'], True]),
  ('counter-clockwise turn #1', [['...', '...'], ['#.', '..'], 0, 0, -1], [['...', '#..'], True]),
  ('control #1',
   [['XX', 'X.', '..', '..', '..'], ['D', 'D', ' '], 0, 4, -3],
   [['XX', 'X.', '..', '..', '..'], False])]]
for label, args, expected in cases[N-1]:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
transparent overhang #1[['#.', '#.'], True][['#.', '#.'], True]Passed
regression transparency #1[['.D.', 'D..', 'X#.', '...', '#X.', '..X'], True][['...', '#..', 'X..', '...', '#X.', '..X'], False]Failed
fault site transparency #1[['DD.', '#..'], True][['DD.', '#..'], True]Passed
regression transparency #2[['##.', '..#', '#D.', '.X.', '.#X', '#..'], True][['##.', '..#', '#..', '.X.', '.#X', '#..'], False]Failed
partial repair boundary #1[['......', '...X..', 'X.#...'], True][['......', '...X..', 'X.#...'], False]Failed
quarter turn #1[['#...', 'D...'], True][['#...', 'D...'], True]Passed
counter-clockwise turn #1[['...', '#..'], True][['...', '#..'], True]Passed
control #1[['.#...#', '.#.#..'], False][['.#...#', '.#.#..'], False]Passed

SHA-256 / 1a01a6b67aac360cf284679927f97d398cfc0d68f0b9017f91a61983090ea9e5

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(grid, prefab, ox, oy, rot):
    p = [list(row) for row in prefab]
    for _ in range(rot % 4):
        p = [list(row) for row in zip(*p[::-1])]
    g = [list(row) for row in grid]
    for r, line in enumerate(p):
        for c, t in enumerate(line):
            if t == ' ':
                continue
            y, x = oy + r, ox + c
            if not (0 <= y < len(g) and 0 <= x < len(g[0])) or g[y][x] == 'X':
                return [grid, False]
            g[y][x] = t
    return [[''.join(row) for row in g], True]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[('transparent overhang #1', [['..', '..'], [' #', ' #'], -1, 0, 0], [['#.', '#.'], True]),
  ('regression transparency #1',
   [['...', '#..', 'X..', '...', '#X.', '..X'], ['.D.', '#.D'], 0, 0, -1],
   [['...', '#..', 'X..', '...', '#X.', '..X'], False]),
  ('fault site transparency #1', [['.#.', '#..'], ['  ', 'DD', '#.'], 0, -1, 4], [['DD.', '#..'], True]),
  ('regression transparency #2',
   [['##.', '..#', '#..', '.X.', '.#X', '#..'], ['.', 'D', '.'], 1, 1, 6],
   [['##.', '..#', '#..', '.X.', '.#X', '#..'], False]),
  ('partial repair boundary #1',
   [['......', '...X..', 'X.#...'], [' ', '.', ' '], -1, -1, 4],
   [['......', '...X..', 'X.#...'], False]),
  ('quarter turn #1', [['....', '....'], ['#D'], 0, 0, 1], [['#...', 'D...'], True]),
  ('counter-clockwise turn #1', [['...', '...'], ['#.', '..'], 0, 0, -1], [['...', '#..'], True]),
  ('control #1', [['.#...#', '.#.#..'], ['  ', '# '], 1, -1, 6], [['.#...#', '.#.#..'], False])],
 [('transparent overhang #1', [['..', '..'], [' #', ' #'], -1, 0, 0], [['#.', '#.'], True]),
  ('fault site transparency #1', [['.#.', '#..'], ['  ', 'DD', '#.'], 0, -1, 4], [['DD.', '#..'], True]),
  ('fault site transparency #2',
   [['..#X.', '.....', '.....', '.XX#.'], ['##D', '#. ', '.# '], 0, 0, 0],
   [['##DX.', '#....', '.#...', '.XX#.'], True]),
  ('partial repair boundary #1',
   [['......', '...X..', 'X.#...'], [' ', '.', ' '], -1, -1, 4],
   [['......', '...X..', 'X.#...'], False]),
  ('regression transparency #1',
   [['.....', 'X..X#', 'X.X.X'], ['. .'], 1, 1, 2],
   [['.....', 'X..X#', 'X.X.X'], False]),
  ('quarter turn #1', [['....', '....'], ['#D'], 0, 0, 1], [['#...', 'D...'], True]),
  ('counter-clockwise turn #1', [['...', '...'], ['#.', '..'], 0, 0, -1], [['...', '#..'], True]),
  ('control #1', [['.#...#', '.#.#..'], ['  ', '# '], 1, -1, 6], [['.#...#', '.#.#..'], False])],
 [('transparent overhang #1', [['..', '..'], [' #', ' #'], -1, 0, 0], [['#.', '#.'], True]),
  ('fault site transparency #1',
   [['...#..', '.#....', '#.....'], ['#.', ' .', '#D'], 2, 0, 5],
   [['..###.', '.#D...', '#.....'], True]),
  ('fault site transparency #2',
   [['#.#', '#..', '#..', '#.X', 'X#.'], [' '], 1, 4, 3],
   [['#.#', '#..', '#..', '#.X', 'X#.'], True]),
  ('regression transparency #1',
   [['..#.X.', '......', '.#..#.', 'XX.#.#', 'X..#.X'], ['  ', ' .', 'D.'], 4, 0, 2],
   [['..#.X.', '......', '.#..#.', 'XX.#.#', 'X..#.X'], False]),
  ('regression transparency #2',
   [['.....#', '#.#..X', 'X.....', '..#XX.', '.#..X.', '...#X.'], ['D', '.'], 2, 3, -1],
   [['.....#', '#.#..X', 'X.....', '..#XX.', '.#..X.', '...#X.'], False]),
  ('quarter turn #1', [['....', '....'], ['#D'], 0, 0, 1], [['#...', 'D...'], True]),
  ('counter-clockwise turn #1', [['...', '...'], ['#.', '..'], 0, 0, -1], [['...', '#..'], True]),
  ('control #1', [['.#...#', '.#.#..'], ['  ', '# '], 1, -1, 6], [['.#...#', '.#.#..'], False])],
 [('transparent overhang #1', [['..', '..'], [' #', ' #'], -1, 0, 0], [['#.', '#.'], True]),
  ('fault site transparency #1',
   [['..#', '...', '...', '##.'], [' #', 'D#'], 1, 2, -3],
   [['..#', '...', '.D.', '###'], True]),
  ('regression transparency #1',
   [['##.', '..#', '#..', '.X.', '.#X', '#..'], ['.', 'D', '.'], 1, 1, 6],
   [['##.', '..#', '#..', '.X.', '.#X', '#..'], False]),
  ('partial repair boundary #1',
   [['.X.', '...', 'X..', '..X', '..#'], ['D.', '. '], 0, -1, 3],
   [['.X.', '...', 'X..', '..X', '..#'], False]),
  ('regression transparency #2',
   [['#...#.', '.##X..', '...X#.', '..XX..', '..#X.#'], ['.', '.'], 1, 1, -1],
   [['#...#.', '...X..', '...X#.', '..XX..', '..#X.#'], True]),
  ('quarter turn #1', [['....', '....'], ['#D'], 0, 0, 1], [['#...', 'D...'], True]),
  ('counter-clockwise turn #1', [['...', '...'], ['#.', '..'], 0, 0, -1], [['...', '#..'], True]),
  ('control #1',
   [['#X', '..', '..', '#.', '#.'], [' D', '.#', '.#'], -1, 2, 3],
   [['#X', '..', '..', '#.', '#.'], False])],
 [('transparent overhang #1', [['..', '..'], [' #', ' #'], -1, 0, 0], [['#.', '#.'], True]),
  ('regression transparency #1',
   [['.....', 'X..X#', 'X.X.X'], ['. .'], 1, 1, 2],
   [['.....', 'X..X#', 'X.X.X'], False]),
  ('regression transparency #2',
   [['..#.X.', '......', '.#..#.', 'XX.#.#', 'X..#.X'], ['  ', ' .', 'D.'], 4, 0, 2],
   [['..#.X.', '......', '.#..#.', 'XX.#.#', 'X..#.X'], False]),
  ('regression transparency #3',
   [['...', '...', '...', 'X#.', 'X#.', '...'], ['.', '.', ' '], 1, 3, -1],
   [['...', '...', '...', 'X..', 'X#.', '...'], True]),
  ('partial repair boundary #1',
   [['..', 'X.', '.X', '.#', '.#', '#.'], ['. '], -1, 3, 1],
   [['..', 'X.', '.X', '.#', '.#', '#.'], False]),
  ('quarter turn #1', [['....', '....'], ['#D'], 0, 0, 1], [['#...', 'D...'], True]),
  ('counter-clockwise turn #1', [['...', '...'], ['#.', '..'], 0, 0, -1], [['...', '#..'], True]),
  ('control #1',
   [['XX', 'X.', '..', '..', '..'], ['D', 'D', ' '], 0, 4, -3],
   [['XX', 'X.', '..', '..', '..'], False])]]
for label, args, expected in cases[N-1]:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
transparent overhang #1[['#.', '#.'], True][['#.', '#.'], True]Passed
regression transparency #1[['...', '#..', 'X..', '...', '#X.', '..X'], False][['...', '#..', 'X..', '...', '#X.', '..X'], False]Passed
fault site transparency #1[['DD.', '#..'], True][['DD.', '#..'], True]Passed
regression transparency #2[['##.', '..#', '#..', '.X.', '.#X', '#..'], False][['##.', '..#', '#..', '.X.', '.#X', '#..'], False]Passed
partial repair boundary #1[['......', '...X..', 'X.#...'], False][['......', '...X..', 'X.#...'], False]Passed
quarter turn #1[['#...', 'D...'], True][['#...', 'D...'], True]Passed
counter-clockwise turn #1[['...', '#..'], True][['...', '#..'], True]Passed
control #1[['.#...#', '.#.#..'], False][['.#...#', '.#.#..'], False]Passed

SHA-256 / 30f2463d1d6f002d123abec125c60364ac56c9737897320cafaae3dca612b583

Verification & scope

Deterministic toy contract stipulated for this model; integer or exact arithmetic only, not a reproduction of any specific game engine. 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.

Observations recorded using Python 3.12.14 at 2026-09-29T14:50:52.430170+00:00.

Case digest / 84865a675d553251a1fc593af1207c28d05c53a8340b12366a744ff7cf503e3f