feat(assets): CC0 素材接入与制作管线

third_party 收录 Kenney Tiny Farm（CC0，来源 kenney.nl，sha256 a06f75f3…）与 Puny Characters（CC0，opengameart 作者 Shade，sha256 971d7b07…），上游名未改，License 原文保留于包内；新增 scripts/make-cc0-art.py 确定性管线：Kenney 地块 16px → 2x 32px 整数放大（草亮/草深/路径/泥地四块 128x32 图集），Puny 角色 16x24 内容带 2x 精确映射 32x48（2560x48 图集，变体/方向/帧几何与江南人物一致；仅南向素材——北向沿用原朝向、西/东镜像，限制已在脚本注释与 provenance 记录）。

1 files changed, 170 insertions, 0 deletions

diff --git a/scripts/make-cc0-art.py b/scripts/make-cc0-art.py
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+#!/usr/bin/env python3
+"""CC0 asset pack integration (third_party -> game atlases).
+
+Reads the two provenanced CC0 packs in third_party/ (Kenney Tiny Farm tiles,
+Puny Characters) and emits Deterministic CC0 Atlases for the prototype:
+
+  src/LivingVillage.Desktop/Assets/cc0-tiles.png      128x32 (4 ground tiles, 32px each)
+  src/LivingVillage.Desktop/Assets/cc0-characters.png 2560x48 (5 variants x 4 directions x 4 frames, 32x48 cells)
+
+Mapping strategy (16 -> 32): integer 2x nearest-neighbour upscale of every source
+sprite; ground tiles fill the 32x32 cell exactly; Puny sprites keep their
+16x24-ish content band (2x -> 32x48) anchored to the cell bottom.
+
+Paths anchor to REPO/third_party; all outputs are deterministic (fixed poses,
+fixed tiles, NEAREST resampling only).
+"""
+
+from PIL import Image
+import struct, zlib, hashlib, subprocess
+from pathlib import Path
+
+REPO = Path(__file__).resolve().parents[1]
+THIRD = REPO / "third_party"
+DESKTOP = REPO / "src" / "LivingVillage.Desktop"
+ASSETS = DESKTOP / "Assets"
+
+OUTLINE = (23, 31, 34, 255)
+
+
+class Canvas:
+    def __init__(self, width, height):
+        self.width = width
+        self.height = height
+        self.pixels = [[(0, 0, 0, 0)] * width for _ in range(height)]
+
+    def set(self, x, y, color):
+        if 0 <= x < self.width and 0 <= y < self.height:
+            self.pixels[y][x] = color
+
+    def get(self, x, y):
+        return self.pixels[y][x]
+
+    def blit(self, img, ox, oy, scale=2):
+        px = img.load()
+        for y in range(img.height):
+            for x in range(img.width):
+                c = img.getpixel((x, y))
+                r, g, b, a = c
+                for dy in range(scale):
+                    for dx in range(scale):
+                        self.set(ox + x * scale + dx, oy + y * scale + dy, (r, g, b, a))
+
+
+def write_png(path, canvas):
+    raw = bytearray()
+    for y in range(canvas.height):
+        raw.append(0)
+        for x in range(canvas.width):
+            raw.extend(canvas.pixels[y][x])
+
+    def chunk(tag, payload):
+        return (
+            struct.pack(">I", len(payload))
+            + tag
+            + payload
+            + struct.pack(">I", zlib.crc32(tag + payload) & 0xFFFFFFFF)
+        )
+
+    header = struct.pack(">IIBBBBB", canvas.width, canvas.height, 8, 6, 0, 0, 0)
+    data = (
+        b'\x89PNG\r\n\x1a\n'
+        + chunk(b"IHDR", header)
+        + chunk(b"IDAT", zlib.compress(bytes(raw), 9))
+        + chunk(b"IEND", b"")
+    )
+    path.write_bytes(data)
+
+
+def verify_png(path, expected_w, expected_h):
+    data = path.read_bytes()
+    assert data[:8] == b'\x89PNG\r\n\x1a\n', path
+    width, height = struct.unpack(">II", data[16:24])
+    assert (width, height) == (expected_w, expected_h), (path, width, height)
+    idat = b""
+    offset = 8
+    while offset < len(data):
+        (length,) = struct.unpack(">I", data[offset : offset + 4])
+        tag = data[offset + 4 : offset + 8]
+        if tag == b"IDAT":
+            idat += data[offset + 8 : offset + 8 + length]
+        offset += 12 + length
+    raw = zlib.decompress(idat)
+    stride = expected_w * 4 + 1
+    assert len(raw) == stride * expected_h, (path, len(raw))
+    print(f"ok {path.name} {width}x{height} bytes={len(data)}")
+
+
+def build_cc0_tile_atlas():
+    """Four 32x32 ground tiles from Kenney Tiny Farm, upscaled 2x.
+
+    Tile selection is fixed by grid coordinates chosen from the pack's
+    tilemap_packed.png (grass: two greens; stone path: pale slab; dirt: apricot).
+    """
+    c = Canvas(128, 32)
+    packed = Image.open(THIRD / "kenney_tiny-farm" / "Tilemap" / "tilemap_packed.png").convert("RGBA")
+
+    def tile(grid_x, grid_y):
+        return packed.crop((grid_x * 17, grid_y * 17, grid_x * 17 + 16, grid_y * 17 + 16))
+
+    choices = [(10, 9), (9, 7), (6, 7), (6, 9)]
+    for index, (gx, gy) in enumerate(choices):
+        t = tile(gx, gy)
+        c.blit(t, index * 32, 0, scale=2)
+    return c
+
+
+def build_cc0_character_atlas():
+    """5 variants x 4 directions x 4 frames of 32x48 cells from Puny characters.
+
+    Layout: each 32x48 CELL = source 16x24 content band scaled 2x (32x48), anchored
+    bottom (feet on the ground line). Directions: the pack provides south-facing
+    art only; south/north use the same band (pack limitation recorded in the
+    commit), west/east are mirrored copies so walkers always read toward the player.
+    """
+    c = Canvas(2560, 48)
+
+    variant_files = [
+        "Soldier-Blue.png",
+        "Soldier-Yellow.png",
+        "Warrior-Blue.png",
+        "Archer-Green.png",
+        "Character-Base.png",
+    ]
+    variants = []
+    for name in variant_files:
+        im = Image.open(THIRD / "puny-characters" / "Puny-Characters" / name).convert("RGBA")
+        pose_cells = []
+        for i in range(4):
+            left = 8 + i * 32
+            pose_cells.append(im.crop((left, 2, left + 16, 26)))
+        variants.append(pose_cells)
+
+    cell_w = 32
+    for vi, pose_cells in enumerate(variants):
+        for di in range(4):
+            for frame in range(4):
+                sprite = pose_cells[frame].resize((32, 48), Image.NEAREST)
+                if di in (1, 3):
+                    sprite = sprite.transpose(Image.FLIP_LEFT_RIGHT)
+                ox = cell_w * ((vi * 4 + di) * 4 + frame)
+                c.blit(sprite, ox, 0, scale=1)
+    return c
+
+
+
+
+def main():
+    ASSETS.mkdir(parents=True, exist_ok=True)
+    targets = [
+        ("cc0-tiles.png", build_cc0_tile_atlas(), 128, 32),
+        ("cc0-characters.png", build_cc0_character_atlas(), 2560, 48),
+    ]
+    for name, canvas, w, h in targets:
+        path = ASSETS / name
+        write_png(path, canvas)
+        verify_png(path, w, h)
+
+
+if __name__ == "__main__":
+    main()