splatter-tennis/assets/_regen.py

# _regen.py — redraw a batch of sprites at real pixel-art resolution, end to end.
#
#   python3 assets/_regen.py shambler_a            # one batch
#   python3 assets/_regen.py --list                # what batches exist
#   python3 assets/_regen.py --all                 # everything not already done
#
# Per batch it: builds a reference sheet from the sprites in the repo, asks the generator to redraw
# them at HIGH art resolution (the style block below is the whole point — the previous prompts asked
# for "big chunky pixel blocks", which is a specification for coarse art), slices with _fine.py,
# colour-matches each frame onto what it replaces, and installs — but only if the sheet passes its
# checks: right number of frames, nothing touching a canvas edge (that is what clipped z_f1), and a
# real gain in inner-edge density (the number that tracks "is the drawing actually finer").
#
# Failures leave the sprites alone and print why, so a batch can just be re-run.
import json, os, subprocess, sys
import numpy as np
from PIL import Image

HERE = os.path.dirname(os.path.abspath(__file__))
SCRATCH = os.environ.get('SPLAT_SCRATCH', '/tmp/splatter-regen')
GEN = os.path.expanduser('~/.claude/skills/generate-image/scripts/generate_image.py')
PY = os.environ.get('SPLAT_PY', sys.executable)

STYLE = (
    "Redraw them as HIGH-RESOLUTION pixel art. The art pixels must be SMALL: build each figure out "
    "of roughly 90 to 110 pixels of height instead of the reference's 40, so there is room for real "
    "detail, and spend it — a face with teeth, sunken eyes and a jawline; individual fingers; "
    "clothing with visible seams, hems, folds and frayed torn edges; laced shoes; four or five "
    "distinct shades per material with fine hatched shading where the light falls away. Keep every "
    "pose, every body proportion, every height, every facing and every wound EXACTLY as in the "
    "reference — only the drawing resolution and the amount of fine detail change. Keep the same "
    "colours. Hard black outline around each figure. The background must be ONE FLAT solid magenta "
    "#FF00FF across the entire canvas — no scenery, no gradient, no vignette. Keep at least 200 "
    "pixels of empty magenta between figures and at least 150 pixels of empty magenta at every edge "
    "of the canvas: no figure or limb may touch or run off an edge. No shadow, no ground line, no text."
)

def batches():
    with open(os.path.join(HERE, '_regen_batches.json')) as f:
        return json.load(f)

# ---------------------------------------------------------------- helpers ----
def ref_sheet(names, out, scale=2.0, gap=220, pad=150):
    ims = [Image.open(os.path.join(HERE, n + '.png')).convert('RGBA') for n in names]
    ims = [i.resize((max(1, int(i.width * scale)), max(1, int(i.height * scale))), Image.NEAREST) for i in ims]
    w = sum(i.width for i in ims) + gap * (len(ims) - 1) + pad * 2
    h = max(i.height for i in ims) + pad * 2
    s = Image.new('RGBA', (w, h), (255, 0, 255, 255))
    x = pad
    for i in ims:
        s.paste(i, (x, h - pad - i.height), i); x += i.width + gap
    s.save(out)
    return out

def density(path):
    """Inner-edge density: how much detail lives INSIDE the silhouette. Coarse art ~0.15, the
    redrawn runner ~0.45. This is the number that matched Oliver's eye."""
    a = np.array(Image.open(path).convert('RGBA'))
    solid = a[..., 3] > 128
    d = np.abs(np.diff(a[..., :3].astype(int), axis=1)).sum(2)
    return round(float(((d > 40) & solid[:, :-1]).sum() / max(1, solid.sum())), 3)

def touches_edge(sheet):
    a = np.array(Image.open(sheet).convert('RGB')).astype(int)
    bg = a[0, 0]
    fg = (((a - bg) ** 2).sum(2) > 3600) & ~(np.minimum(a[..., 0], a[..., 2]) > a[..., 1] + 40)
    return bool(fg[0].any() or fg[-1].any() or fg[:, 0].any() or fg[:, -1].any())

def colour_match(src, dst_name):
    """Fit the new frame onto the palette statistics of the sprite it replaces, so a redrawn body
    does not change colour halfway through a walk cycle."""
    op = lambda x: x[..., 3] > 200
    old = np.array(Image.open(os.path.join(HERE, dst_name + '.png')).convert('RGBA'), dtype=float)
    new = np.array(Image.open(src).convert('RGBA'), dtype=float)
    po, pn = old[op(old)][:, :3], new[op(new)][:, :3]
    m = op(new)
    px = (new[m][:, :3] - pn.mean(0)) / np.maximum(pn.std(0), 1e-6) * po.std(0) + po.mean(0)
    new[m] = np.concatenate([np.clip(px, 0, 255), new[m][:, 3:]], axis=1)
    Image.fromarray(new.astype('uint8'), 'RGBA').save(src)

# ------------------------------------------------------------------- run ----
def run(name, spec, dry=False):
    os.makedirs(SCRATCH, exist_ok=True)
    sprites = spec['sprites']
    lead = spec.get('ref')                       # generated for scale, thrown away after
    ref = ref_sheet(([lead] if lead else []) + sprites, f'{SCRATCH}/{name}_ref.png', spec.get('scale', 2.0))
    sheet = f'{SCRATCH}/{name}_hi.png'
    prompt = f"{spec['subject']} {STYLE}"
    if dry:
        print(f'[{name}] would generate {len(sprites)} frames: {", ".join(sprites)}'); return True
    print(f'[{name}] generating {len(sprites)} frames...')
    r = subprocess.run([PY, GEN, prompt, '--input', ref, '--output', sheet],
                       capture_output=True, text=True, cwd=os.path.dirname(HERE))
    if not os.path.exists(sheet):
        print(f'[{name}] FAILED: generator returned no image\n{r.stdout[-400:]}'); return False
    if touches_edge(sheet):
        print(f'[{name}] REJECTED: a figure runs off the canvas edge — re-run'); return False
    outs = [f'{SCRATCH}/{name}_{i}.png' for i in range(len(sprites) + (1 if lead else 0))]
    cut = ['--cut', spec['cut']] if spec.get('cut') else []
    r = subprocess.run([PY, os.path.join(HERE, '_fine.py'), sheet, *outs,
                        '--anchor', str(spec.get('anchor', 0)), '--h', str(spec.get('h', 224)), *cut],
                       capture_output=True, text=True)
    print(r.stdout.strip() or r.stderr.strip())
    if r.returncode or not all(os.path.exists(o) for o in outs):
        print(f'[{name}] REJECTED: slicing failed (frames merged?) — re-run or add "cut"'); return False
    if lead: outs = outs[1:]                     # the scale reference is not installed
    before = [density(os.path.join(HERE, s + '.png')) for s in sprites]
    after = [density(o) for o in outs]
    # 1.25x, not 1.5x: a sheet that already has blood on it starts with a high edge density, so a
    # genuinely finer redraw of a wounded body scores a smaller gain than a clean one.
    if sum(after) / len(after) < sum(before) / len(before) * 1.25:
        print(f'[{name}] REJECTED: not finer than what it replaces {before} -> {after}'); return False
    for o, s in zip(outs, sprites):
        colour_match(o, s)
        Image.open(o).save(os.path.join(HERE, s + '.png'))
    print(f'[{name}] installed. detail {before} -> {after}')
    return True

if __name__ == '__main__':
    args = sys.argv[1:]
    B = batches()
    if not args or '--list' in args:
        for k, v in B.items(): print(f'{k:16s} {len(v["sprites"]):2d} frames  {", ".join(v["sprites"])}')
        sys.exit()
    dry = '--dry' in args
    tries = 3                                    # a rejected sheet is usually just a bad roll:
    for a in args:                               # frames merged, or a limb off the canvas
        if a.startswith('--tries='): tries = int(a.split('=')[1])
    names = list(B) if '--all' in args else [a for a in args if not a.startswith('--')]
    bad = []
    for n in names:
        for attempt in range(1, tries + 1):
            if run(n, B[n], dry): break
            print(f'[{n}] attempt {attempt}/{tries} rejected')
        else:
            bad.append(n)
    print('\nFAILED BATCHES (re-run):', ' '.join(bad) if bad else 'none')