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synced 2026-11-11 12:27:47 +01:00
Krzysztof kuhy Rudnicki
d1ca1e3d5b
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Flutter repos now fail the repo contract when a launcher icon's ink is not on the shared 340px circle (png_ink), the launcher label breaks the naming rule (capital, ASCII letters, <= 10 chars, <= 522 wide in GoogleSansFlex), or an applicationIdSuffix variant still carries the LAUNCHER category. hook_sync rewrites a repo's stale repo-contract `files:` line to the widened template. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_017k9j5dbjenpfZj7dh2faPN
93 lines
2.8 KiB
Python
93 lines
2.8 KiB
Python
"""Tiny RGBA PNG encoder for icon fixtures (stdlib only, like the gate)."""
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from __future__ import annotations
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import math
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import struct
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import zlib
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from collections.abc import Callable
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from pathlib import Path
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SIG = b"\x89PNG\r\n\x1a\n"
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SIZE = 1024
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INK = bytes((0xB8, 0x86, 0x2E, 0xFF))
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FAINT = bytes((0xB8, 0x86, 0x2E, 0x7F)) # alpha 127: fringe, not ink
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CLEAR = bytes(4)
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def disk_rows(
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radius: float, cx: float = 512.0, cy: float = 512.0, size: int = SIZE
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) -> list[bytes]:
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"""RGBA rows of a solid disk; pixel centres within `radius` are inked."""
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rows = []
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for y in range(size):
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dy = y + 0.5 - cy
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if abs(dy) >= radius:
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rows.append(CLEAR * size)
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continue
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half = math.sqrt(radius * radius - dy * dy)
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x0 = max(0, math.ceil(cx - half - 0.5))
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x1 = min(size, math.floor(cx + half - 0.5) + 1)
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rows.append(CLEAR * x0 + INK * (x1 - x0) + CLEAR * (size - x1))
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return rows
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def _paeth(a: int, b: int, c: int) -> int:
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p = a + b - c
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pa, pb, pc = abs(p - a), abs(p - b), abs(p - c)
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if pa <= pb and pa <= pc:
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return a
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return b if pb <= pc else c
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def _filter(kind: int, row: bytes, prior: bytes) -> bytes:
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"""Apply PNG filter `kind` (0-4, 4 bytes per pixel) to one raw row."""
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if kind == 0:
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return row
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out = bytearray(len(row))
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for i, value in enumerate(row):
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a = row[i - 4] if i >= 4 else 0
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b = prior[i]
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c = prior[i - 4] if i >= 4 else 0
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pred = (0, a, b, (a + b) // 2, _paeth(a, b, c))[kind]
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out[i] = (value - pred) & 255
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return bytes(out)
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def chunk(kind: bytes, body: bytes) -> bytes:
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"""One PNG chunk: length, type, body, CRC."""
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crc = struct.pack(">I", zlib.crc32(kind + body))
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return struct.pack(">I", len(body)) + kind + body + crc
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def encode(
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rows: list[bytes],
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*,
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filters: Callable[[int], int] | None = None,
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size: int = SIZE,
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depth: int = 8,
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colour: int = 6,
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interlace: int = 0,
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iend: bool = True,
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) -> bytes:
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"""PNG bytes for `rows`; `filters(y)` picks each row's filter type."""
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prior = bytes(len(rows[0]))
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raw = bytearray()
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for y, row in enumerate(rows):
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kind = filters(y) if filters else 0
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raw.append(kind)
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raw += _filter(kind, row, prior)
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prior = row
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ihdr = struct.pack(">IIBBBBB", size, size, depth, colour, 0, 0, interlace)
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body = chunk(b"IHDR", ihdr) + chunk(b"IDAT", zlib.compress(bytes(raw), 1))
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return SIG + body + (chunk(b"IEND", b"") if iend else b"")
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def write_icon(
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path: Path, radius: float = 340, cx: float = 512, cy: float = 512
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) -> Path:
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"""Write a disk icon foreground to `path` (parents created)."""
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path.parent.mkdir(parents=True, exist_ok=True)
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path.write_bytes(encode(disk_rows(radius, cx, cy)))
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return path
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