High-res interface icons: tools, towers, traps, doors, spells, orders and siege

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tools/cut_icons.py

@@ -0,0 +1,72 @@
+#!/usr/bin/env python3
+"""Cut a generated sheet of icons (a grid on a flat magenta background) into transparent icons
+for the high-res atlas: every cell keyed (only nearly pure magenta goes, so violet glows stay),
+cropped to its icon, centred in a square with a small margin and scaled down without fringes,
+the alpha made hard.
+
+Usage:
+  cut_icons.py raw.png out_prefix --grid ROWSxCOLS [--count N] [--margin 0.06]
+
+Writes out_prefix-64.png and out_prefix-128.png: the icons side by side in reading order, and
+out_prefix-preview.png (on a grey background, 2x). Needs Pillow.
+"""
+import argparse
+
+from PIL import Image
+
+
+def keyed(p):
+    r, g, b = p[:3]
+    return r > 170 and b > 170 and g < 90 and abs(r - b) < 70
+
+
+def main():
+    ap = argparse.ArgumentParser()
+    ap.add_argument("raw")
+    ap.add_argument("out")
+    ap.add_argument("--grid", required=True)
+    ap.add_argument("--count", type=int, default=0)
+    ap.add_argument("--margin", type=float, default=0.06)
+    a = ap.parse_args()
+    rows, cols = (int(v) for v in a.grid.split("x"))
+    n = a.count or rows * cols
+
+    img = Image.open(a.raw).convert("RGBA")
+    px = img.load()
+    for y in range(img.height):
+        for x in range(img.width):
+            if keyed(px[x, y]):
+                px[x, y] = (0, 0, 0, 0)
+    icons = []
+    for i in range(n):
+        r, c = divmod(i, cols)
+        cell = img.crop((c * img.width // cols, r * img.height // rows, (c + 1) * img.width // cols, (r + 1) * img.height // rows))
+        box = cell.getchannel("A").point(lambda v: 255 if v > 0 else 0).getbbox() or (0, 0, cell.width, cell.height)
+        icon = cell.crop(box)
+        side = int(max(icon.size) * (1 + 2 * a.margin))
+        sq = Image.new("RGBA", (side, side), (0, 0, 0, 0))
+        sq.paste(icon, ((side - icon.width) // 2, (side - icon.height) // 2))
+        icons.append(sq)
+    for size in (64, 128):
+        strip = Image.new("RGBA", (size * n, size), (0, 0, 0, 0))
+        for k, sq in enumerate(icons):
+            small = sq.resize((size, size), Image.BOX)
+            sp = small.load()
+            for y in range(size):
+                for x in range(size):
+                    r, g, b, al = sp[x, y]
+                    if al < 110:
+                        sp[x, y] = (0, 0, 0, 0)
+                    else:
+                        f = 255 / al
+                        sp[x, y] = (min(255, int(r * f)), min(255, int(g * f)), min(255, int(b * f)), 255)
+            strip.paste(small, (k * size, 0))
+        strip.save(f"{a.out}-{size}.png")
+    prev = Image.new("RGBA", (64 * n, 64), (80, 76, 84, 255))
+    prev.alpha_composite(Image.open(f"{a.out}-64.png"))
+    prev.resize((prev.width * 2, prev.height * 2), Image.NEAREST).save(f"{a.out}-preview.png")
+    print(f"{a.out}: {n} icons")
+
+
+if __name__ == "__main__":
+    main()