coco_playgame/scripts/slice-imagegen-assets.py

from pathlib import Path
from PIL import Image

ROOT = Path(__file__).resolve().parents[1]
SRC = ROOT / "assets" / "resources" / "sprites" / "imagegen"
OUT = SRC / "frames"


def alpha_crop(tile, padding=6):
    alpha = tile.getchannel("A")
    bbox = alpha.getbbox()
    if not bbox:
      return tile
    left, top, right, bottom = bbox
    left = max(0, left - padding)
    top = max(0, top - padding)
    right = min(tile.width, right + padding)
    bottom = min(tile.height, bottom + padding)
    return tile.crop((left, top, right, bottom))


def slice_row(file_name, names):
    image = Image.open(SRC / file_name).convert("RGBA")
    tile_w = image.width / len(names)
    OUT.mkdir(parents=True, exist_ok=True)
    for index, name in enumerate(names):
        left = round(index * tile_w)
        right = round((index + 1) * tile_w)
        tile = image.crop((left, 0, right, image.height))
        alpha_crop(tile).save(OUT / f"{name}.png")


def slice_grid(file_name, names, cols, rows):
    image = Image.open(SRC / file_name).convert("RGBA")
    tile_w = image.width / cols
    tile_h = image.height / rows
    OUT.mkdir(parents=True, exist_ok=True)
    for index, name in enumerate(names):
        col = index % cols
        row = index // cols
        left = round(col * tile_w)
        top = round(row * tile_h)
        right = round((col + 1) * tile_w)
        bottom = round((row + 1) * tile_h)
        tile = image.crop((left, top, right, bottom))
        alpha_crop(tile, 4).save(OUT / f"{name}.png")


slice_row("hero_spritesheet.png", [
    "hero_idle",
    "hero_walk_1",
    "hero_walk_2",
    "hero_walk_3",
    "hero_walk_4",
    "hero_jump_rise",
    "hero_jump_fall",
    "hero_landing",
])

slice_row("enemies_spritesheet.png", [
    "spore_idle",
    "spore_walk_1",
    "spore_walk_2",
    "spore_hit",
    "wing_idle",
    "wing_flap_1",
    "wing_flap_2",
    "wing_hit",
    "turret_idle",
    "turret_aim",
    "turret_fire",
    "turret_damaged",
])

slice_row("boss_star_hive_spritesheet.png", [
    "boss_idle_closed",
    "boss_idle_pulse",
    "boss_attack_charge",
    "boss_tentacle_sweep",
    "boss_damaged",
    "boss_core_enraged",
])

slice_grid("projectiles_spritesheet.png", [
    "rifle_1",
    "rifle_2",
    "rifle_3",
    "rifle_4",
    "flame_1",
    "flame_2",
    "flame_3",
    "flame_4",
    "rail_1",
    "rail_2",
    "acid_1",
    "acid_2",
    "acid_3",
    "acid_4",
    "impact_1",
    "impact_2",
    "impact_3",
    "impact_4",
    "muzzle_1",
    "muzzle_2",
], 10, 2)

for path in sorted(OUT.glob("*.png")):
    with Image.open(path) as image:
        print(f"{path.name}: {image.width}x{image.height}")