fixed paths

gerber_to_pm4n.py

@@ -242,7 +242,16 @@ def main():
         if not p.exists():
             sys.exit(f"ERROR: {label} file not found: {p}")
 
-    out    = Path(args.output) if args.output else gbr.with_suffix('.pm4n')
+    if args.output:
+        out = Path(args.output)
+    else:
+        # If in 'output/gerbers/', default to 'output/pm4n/'
+        parent = gbr.parent
+        if parent.name == 'gerbers' and parent.parent.name == 'output':
+            out = parent.parent / 'pm4n' / gbr.with_suffix('.pm4n').name
+        else:
+            out = gbr.with_suffix('.pm4n')
+
     pos_mm = None
     if args.pos:
         try: