diff --git a/static/cq-viewer.html b/static/cq-viewer.html
index 89754b1..197b63d 100644
--- a/static/cq-viewer.html
+++ b/static/cq-viewer.html
@@ -26,15 +26,33 @@
 		let viewer = null;
 		let model = [ {}, {} ];
 
+		let cam = {
+			position:undefined,
+			target:undefined,
+			quaternion:undefined,
+			zoom:undefined,
+		}
+		Object.assign(options, cam);
+
 		function nc(change) {
-			// console.debug('viewer info:', JSON.stringify(change, null, 2));
+			// position, quaternion, target, zoom
+			if(change.position)
+				cam.position = change.position.new;
+			if(change.quaternion)
+				cam.quaternion = change.quaternion.new;
+			if(change.target)
+				cam.target = change.target.new;
+			if(change.zoom)
+				cam.zoom = change.zoom.new;
+			Object.assign(options, cam);
 		}
 
 		function update_viewer() {
-			container.innerHTML = '';
-			viewer = new Viewer(container, options, nc);
-			viewer.trimUI(["axes", "axes0", "grid", "ortho", "more", "help"], false);
-			render(model);
+			// container.innerHTML = '';
+			if(!viewer)
+				viewer = new Viewer(container, options, nc);
+			// viewer.trimUI(["axes", "axes0", "grid", "ortho", "more", "help"], false);
+			render(model); 
 		}
 
 		function render() {