diff -r ec07ddc1a4a4 -r fae0dd90663b rust/mapgen/src/lib.rs
--- a/rust/mapgen/src/lib.rs	Fri Nov 09 14:12:00 2018 +0300
+++ b/rust/mapgen/src/lib.rs	Fri Nov 09 14:15:22 2018 +0300
@@ -141,6 +141,7 @@
         if let Some(border_sprite) = theme.border_texture() {
             assert!(border_sprite.height() <= 512);
             let border_width = (border_sprite.height() / 2) as u8;
+            let border_sprite = border_sprite.to_tiled();
 
             let mut offsets = vec![255u8; land.width()];