icons: ship the leather mark, with a simplified version for tab size

Christian's leather patch art is the app icon at 180px and up. It cannot be
the favicon: leather grain and stitching turn to mud below 48px, and the
pulse is black on brown, which is not enough contrast in a tab bar.

So the set is two-tier. Sizes 180 and above come from the leather art;
16, 32, 48 and the .ico come from a flat source whose spike geometry was
measured off the original (left tail at 52% height, peak at 42% width,
trough at 54%, right tail at 84%). Same colours sampled from the leather
body, so the small mark reads as the same object rather than a different
logo.

make_icons.py gained --small-from for this: one command builds both tiers.

Signed-off-by: Christian Sass <csass@binaryranch.com>

icons/source-flat.svg

@@ -0,0 +1,6 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="1024" height="1024" viewBox="0 0 1024 1024">
+  <rect width="1024" height="1024" rx="224" fill="#583828"/>
+  <path d="M164 533 H352 L433 200 L540 840 L655 533 H859"
+        fill="none" stroke="#f0ede8" stroke-width="74"
+        stroke-linecap="square" stroke-linejoin="miter"/>
+</svg>

icons/source-small.svg

@@ -0,0 +1,6 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="1024" height="1024" viewBox="0 0 1024 1024">
+  <rect width="1024" height="1024" rx="224" fill="#583828"/>
+  <path d="M180 520 H420 L512 250 L604 790 L700 520 H844"
+        fill="none" stroke="#f0ede8" stroke-width="132"
+        stroke-linecap="square" stroke-linejoin="miter"/>
+</svg>

tools/make_icons.py

@@ -61,21 +61,29 @@ def main():
     ap = argparse.ArgumentParser()
     ap.add_argument("source", help="square-ish .svg or .png/.jpg mark")
     ap.add_argument("--out-dir", default="icons")
+    ap.add_argument("--small-from", default="",
+                    help="optional simpler source used for 16/32/48 and the .ico, "
+                         "because fine detail dies at tab size")
+    ap.add_argument("--small-max", type=int, default=48)
     args = ap.parse_args()
 
     if not os.path.exists(args.source):
         sys.exit(f"no such file: {args.source}")
 
     master = load_square(args.source)
+    small = load_square(args.small_from) if args.small_from else None
     os.makedirs(args.out_dir, exist_ok=True)
     for size in SIZES:
+        src = small if (small and size <= args.small_max) else master
         out = os.path.join(args.out_dir, f"icon-{size}.png")
-        master.resize((size, size), RESAMPLE).save(out)
-        print(f"  {out}")
+        src.resize((size, size), RESAMPLE).save(out)
+        print(f"  {out}{'  (simplified)' if src is small else ''}")
 
     ico_path = os.path.join(args.out_dir, "favicon.ico")
-    master.resize((256, 256), RESAMPLE).save(ico_path, sizes=[(s, s) for s in ICO_SIZES])
-    print(f"  {ico_path}  ({', '.join(str(s) for s in ICO_SIZES)})")
+    (small or master).resize((256, 256), RESAMPLE).save(
+        ico_path, sizes=[(s, s) for s in ICO_SIZES])
+    print(f"  {ico_path}  ({', '.join(str(s) for s in ICO_SIZES)})"
+          f"{'  (simplified)' if small else ''}")
 
     print(f"\n{len(SIZES) + 1} files in {args.out_dir}/")
     print("upload icon-512.png as the org avatar on both forges; the rest ship with the app")