feat: improve first-session combat and visual assets

scripts/build-equipment-icons.py

@@ -0,0 +1,61 @@
+from __future__ import annotations
+
+import argparse
+from pathlib import Path
+
+from PIL import Image
+
+
+ROOT = Path(__file__).resolve().parents[1]
+DEFAULT_SOURCE_DIR = ROOT / "tmp" / "imagegen"
+OUTPUT_ROOT = ROOT / "src" / "assets" / "images" / "ui" / "equipment-icons"
+
+
+def parse_args() -> argparse.Namespace:
+    parser = argparse.ArgumentParser(
+        description="Build centered 128px and 32px equipment icons from transparent source art."
+    )
+    parser.add_argument("ids", nargs="+", help="Equipment ids whose <id>-alpha.png source should be built.")
+    parser.add_argument("--source-dir", type=Path, default=DEFAULT_SOURCE_DIR)
+    return parser.parse_args()
+
+
+def fit_icon(source: Image.Image, size: int) -> Image.Image:
+    rgba = source.convert("RGBA")
+    bounds = rgba.getchannel("A").getbbox()
+    if bounds is None:
+        raise ValueError("source image has no visible pixels")
+
+    cropped = rgba.crop(bounds)
+    inner_size = max(1, round(size * 0.88))
+    scale = min(inner_size / cropped.width, inner_size / cropped.height)
+    resized_size = (
+        max(1, round(cropped.width * scale)),
+        max(1, round(cropped.height * scale)),
+    )
+    resized = cropped.resize(resized_size, Image.Resampling.LANCZOS)
+    canvas = Image.new("RGBA", (size, size), (0, 0, 0, 0))
+    offset = ((size - resized.width) // 2, (size - resized.height) // 2)
+    canvas.alpha_composite(resized, offset)
+    return canvas
+
+
+def main() -> None:
+    args = parse_args()
+    for size in (128, 32):
+        (OUTPUT_ROOT / str(size)).mkdir(parents=True, exist_ok=True)
+
+    for item_id in args.ids:
+        source_path = args.source_dir / f"{item_id}-alpha.png"
+        if not source_path.exists():
+            raise FileNotFoundError(f"missing transparent source: {source_path}")
+
+        with Image.open(source_path) as source:
+            for size in (128, 32):
+                output_path = OUTPUT_ROOT / str(size) / f"{item_id}.png"
+                fit_icon(source, size).save(output_path, optimize=True)
+                print(f"Wrote {output_path.relative_to(ROOT)}")
+
+
+if __name__ == "__main__":
+    main()