diff --git a/src/body.rs b/src/body.rs
index c2a3b20..f80726e 100644
--- a/src/body.rs
+++ b/src/body.rs
@@ -58,18 +58,13 @@ impl MouseInterpolationState {
 		match self.interpolation {
 			MouseInterpolation::First => self.mouse0,
 			MouseInterpolation::Lerp => {
-				//a 5 hour run uses 45 bits of TIME
-				//mouse positions may accumulate on a map where the player spins, especially for high dpi...
-				let x0=self.mouse0.x as i128;
-				let y0=self.mouse0.y as i128;
-				let x1=self.mouse1.x as i128;
-				let y1=self.mouse1.y as i128;
-				let t1t=(self.time1-time) as i128;
-				let tt0=(time-self.time0) as i128;
-				let dt=(self.time1-self.time0) as i128;
-				glam::ivec2(
-					((x0*t1t+x1*tt0)/dt) as i32,
-					((y0*t1t+y1*tt0)/dt) as i32)
+				let m0=self.mouse0.as_i64vec2();
+				let m1=self.mouse1.as_i64vec2();
+				//these are deltas
+				let t1t=(self.time1-time) as i64;
+				let tt0=(time-self.time0) as i64;
+				let dt=(self.time1-self.time0) as i64;
+				((m0*t1t+m1*tt0)/dt).as_ivec2()
 			}
 		}
 	}