diff --git a/src/bin/flat/tube/mod.rs b/src/bin/flat/tube/mod.rs
index 81ee9e6..7bcf8de 100644
--- a/src/bin/flat/tube/mod.rs
+++ b/src/bin/flat/tube/mod.rs
@@ -185,7 +185,7 @@ fn test_rect() {
 
 mod coords {
 	use glam::{Mat2, Vec2, vec2};
-	use crate::riemann::{Decomp2, Metric};
+	use crate::riemann::Metric;
 	use crate::types::{Location, Ray};
 	use super::{Rect, Tube};
 
@@ -201,14 +201,11 @@ mod coords {
 
 	trait MetricCS: FlatCoordinateSystem<Vec2> {
 		fn global_metric(&self) -> &impl Metric;
-		fn sqrt_at_global(&self, pos: Vec2) -> Decomp2 {
-			self.global_metric().sqrt_at(pos)
-		}
 		fn flat_to_global_tfm_at(&self, pos: Vec2) -> Mat2 {
-			self.sqrt_at_global(self.flat_to_global(pos)).inverse().into()
+			self.global_metric().sqrt_at(self.flat_to_global(pos)).inverse().into()
 		}
 		fn global_to_flat_tfm_at(&self, pos: Vec2) -> Mat2 {
-			self.sqrt_at_global(pos).into()
+			self.global_metric().sqrt_at(pos).into()
 		}
 	}