diff --git a/index.js b/index.js
index 91352d4..feff417 100644
--- a/index.js
+++ b/index.js
@@ -103,8 +103,7 @@ const stuff = {
 function handleKeys(params) {
     const move = (forward, right) => {
         const dir = [right, 0, -forward, 1.0];
-        const camori = params.camera.orientation;
-        const ori = se3.rotxyz(...camori);
+        const ori = se3.roty(params.camera.orientation[1]);
         const tf = se3.apply(ori, dir);
 
         if (params.flying) {
@@ -439,6 +438,10 @@ async function main() {
         const moveListener = e => {
             params.camera.orientation[1] -= e.movementX / 500;
             params.camera.orientation[0] -= e.movementY / 500;
+
+            params.camera.orientation[0] = Math.min(Math.max(
+                params.camera.orientation[0], -Math.PI / 2
+            ), Math.PI / 2);
         };
         const changeListener = () => {
             if (document.pointerLockElement === canvas) {