Provisional additions of under-bump material and redistribution
layer vias (testing whether these layers can be derived or need
to be explicitly drawn).

sky130/magic/sky130.tech

diff --git a/sky130/magic/sky130.tech b/sky130/magic/sky130.tech
index 7d87b56..e003d7b 100644
--- a/sky130/magic/sky130.tech
+++ b/sky130/magic/sky130.tech
@@ -1218,6 +1218,20 @@
 	labels  *metrdl port
 	calma	74 5
 
+  layer PI1	*metrdl
+	and	padl,glass
+	# Test only---needs GDS layer number
+
+  layer	UBM	*metrdl
+	shrink	50000
+	grow	40000
+	# Test only---needs GDS layer number
+	
+  layer	PI2	*metrdl
+	shrink	50000
+	grow	25000
+	# Test only---needs GDS layer number
+
 #endif REDISTRIBUTION
 
 #----------------------------------------------------------------