diff --git a/src/circle.rs b/src/circle.rs
index 91da5c4..71cde03 100644
--- a/src/circle.rs
+++ b/src/circle.rs
@@ -55,6 +55,12 @@ impl Circle {
 
         debug!("bb: {}..{} {}..{}",bb.left(), bb.right(), bb.top(), bb.bottom() );
         
+        if bb.width() > 2048.0 || bb.height() > 2048.0 {
+            // BUG: intial window size for wasm32 target tends to be significantly
+            //      wider than in reality 
+            return Circle::default()
+        }
+
         Self {
             r: rand::thread_rng().gen_range(20.0..50.0),
             c: Pos2 {