diff --git a/res/threejs/SolveSpaceControls.js b/res/threejs/SolveSpaceControls.js
index cde7eb24..fbee7da2 100644
--- a/res/threejs/SolveSpaceControls.js
+++ b/res/threejs/SolveSpaceControls.js
@@ -155,8 +155,8 @@ SolvespaceControls = function(object, domElement) {
 
         switch (event.button) {
             case 0:
-                _rotateCur.set(event.screenX / window.devicePixelRatio,
-                               event.screenY / window.devicePixelRatio);
+                _rotateCur.set(event.screenX,
+                               event.screenY);
                 _rotatePrev.copy(_rotateCur);
                 document.addEventListener('mousemove', mousemove_rotate, false);
                 document.addEventListener('mouseup', mouseup, false);
@@ -184,8 +184,8 @@ SolvespaceControls = function(object, domElement) {
     }
 
     function mousemove_rotate(event) {
-        _rotateCur.set(event.screenX / window.devicePixelRatio,
-                       event.screenY / window.devicePixelRatio);
+        _rotateCur.set(event.screenX,
+                       event.screenY);
         var diff = new THREE.Vector2().subVectors(_rotateCur, _rotatePrev)
             .multiplyScalar(1 / object.zoomScale);
         object.rotate(-0.3 * Math.PI / 180 * diff.x * object.zoomScale,
@@ -199,7 +199,7 @@ SolvespaceControls = function(object, domElement) {
         _offsetCur.set(event.screenX / window.devicePixelRatio,
                        event.screenY / window.devicePixelRatio);
         var diff = new THREE.Vector2().subVectors(_offsetCur, _offsetPrev)
-            .multiplyScalar(1 / object.zoomScale);
+            .multiplyScalar(window.devicePixelRatio / object.zoomScale);
         object.offsetProj(diff.x, -diff.y);
         _changed = true;
         _offsetPrev.copy(_offsetCur);
@@ -507,3 +507,4 @@ solvespace = function(obj, params) {
         return new THREE.LineSegments(geometry, material);
     }
 };
+