diff --git a/src/physics_worker.rs b/src/physics_worker.rs
index e7c278c..7c294ac 100644
--- a/src/physics_worker.rs
+++ b/src/physics_worker.rs
@@ -37,7 +37,7 @@ impl MouseInterpolator{
 		let t0=self.queue[0].time;
 		let mut iter=self.queue.iter();
 		//find a mouse input
-		let mouse0=None;
+		let mut mouse0=None;
 		iter.take_while(|&ins|{
 			match ins.instruction{
 				InputInstruction::MoveMouse(m)=>{
@@ -50,6 +50,9 @@ impl MouseInterpolator{
 				},
 			}
 		});
+		if mouse0.is_none(){
+			return;
+		}
 		let mut mouse1=None;
 		for ins in iter{
 			//fill mouse0