diff --git a/crates/cord-decompile/src/sparse_grid.rs b/crates/cord-decompile/src/sparse_grid.rs
index 5b97e05..3dd038a 100644
--- a/crates/cord-decompile/src/sparse_grid.rs
+++ b/crates/cord-decompile/src/sparse_grid.rs
@@ -150,7 +150,7 @@ fn sdf_gradient(mesh: &TriangleMesh, bvh: &BVH, p: Vec3) -> Vec3 {
     let dx = bvh.signed_distance(mesh, Vec3::new(p.x + eps, p.y, p.z))
            - bvh.signed_distance(mesh, Vec3::new(p.x - eps, p.y, p.z));
     let dy = bvh.signed_distance(mesh, Vec3::new(p.x, p.y + eps, p.z))
-           - bvh.signed_distance(mesh, Vec3::new(p.x, p.y, p.z - eps));
+           - bvh.signed_distance(mesh, Vec3::new(p.x, p.y - eps, p.z));
     let dz = bvh.signed_distance(mesh, Vec3::new(p.x, p.y, p.z + eps))
            - bvh.signed_distance(mesh, Vec3::new(p.x, p.y, p.z - eps));
     Vec3::new(dx, dy, dz).normalized()