diff --git a/web/app/3d/cad-utils.js b/web/app/3d/cad-utils.js
index 8401e688..7980915f 100644
--- a/web/app/3d/cad-utils.js
+++ b/web/app/3d/cad-utils.js
@@ -5,8 +5,8 @@ import * as math from '../math/math'
 import {Matrix3, AXIS, ORIGIN} from '../math/l3space'
 import Counters from './counters'
 import {Solid} from './solid'
+import DPR from '../utils/dpr'
 
-export const DPR = (window.devicePixelRatio) ? window.devicePixelRatio : 1;
 export const FACE_COLOR =  0xB0C4DE;
 
 export function createSquare(width) {
diff --git a/web/app/3d/solid.js b/web/app/3d/solid.js
index 24b46438..cb731cde 100644
--- a/web/app/3d/solid.js
+++ b/web/app/3d/solid.js
@@ -3,7 +3,8 @@ import Vector from '../math/vector'
 import Counters from './counters'
 import {reconstructSketchBounds} from './workbench'
 import {Matrix3, AXIS} from '../math/l3space'
-import {DPR, arrFlatten1L} from './cad-utils'
+import {arrFlatten1L} from './cad-utils'
+import DPR from '../utils/dpr'
 
 /** @constructor */
 export function Solid(csg, material, type) {
@@ -201,12 +202,8 @@ function SketchFace(solid, csgGroup) {
   this.curvedSurfaces = null;
 }
 
-if (typeof THREE !== "undefined") {
-  SketchFace.prototype.SKETCH_MATERIAL = new THREE.LineBasicMaterial({
-    color: 0xFFFFFF, linewidth: 3/DPR});
-  SketchFace.prototype.WIREFRAME_MATERIAL = new THREE.LineBasicMaterial({
-    color: 0x2B3856, linewidth: 3/DPR});
-}
+SketchFace.prototype.SKETCH_MATERIAL = new THREE.LineBasicMaterial({color: 0xFFFFFF, linewidth: 3/DPR});
+SketchFace.prototype.WIREFRAME_MATERIAL = new THREE.LineBasicMaterial({color: 0x2B3856, linewidth: 3/DPR});
 
 SketchFace.prototype.calcBasis = function() {
   var normal = new Vector().setV(this.csgGroup.plane.normal);
diff --git a/web/app/3d/viewer.js b/web/app/3d/viewer.js
index 15c73f2d..6b6c1b44 100644
--- a/web/app/3d/viewer.js
+++ b/web/app/3d/viewer.js
@@ -1,5 +1,6 @@
 import * as cad_utils from './cad-utils'
 import {Matrix3, AXIS, ORIGIN} from '../math/l3space'
+import DPR from '../utils/dpr'
 
 function Viewer(bus) {
   this.bus = bus;
@@ -18,7 +19,7 @@ function Viewer(bus) {
   scene.add(light);
 
   var renderer = new THREE.WebGLRenderer();
-  renderer.setPixelRatio(cad_utils.DPR);
+  renderer.setPixelRatio(DPR);
   renderer.setClearColor(0x808080, 1);
   renderer.setSize( window.innerWidth, window.innerHeight );
   document.body.appendChild( renderer.domElement );
@@ -75,7 +76,7 @@ function Viewer(bus) {
   }
 
   function addAxis(axis, color) {
-    var lineMaterial = new THREE.LineBasicMaterial({color: color, linewidth: 1/cad_utils.DPR});
+    var lineMaterial = new THREE.LineBasicMaterial({color: color, linewidth: 1/DPR});
     var axisGeom = new THREE.Geometry();
     axisGeom.vertices.push(axis.multiply(-1000).three());
     axisGeom.vertices.push(axis.multiply(1000).three());
@@ -172,7 +173,7 @@ function SelectionManager(viewer, selectionColor, readOnlyColor, defaultColor) {
     arrow.matrixAutoUpdate = false;
     arrow.line.renderOrder = 1e11;
     arrow.cone.renderOrder = 1e11;
-    arrow.line.material.linewidth =  1/cad_utils.DPR;
+    arrow.line.material.linewidth =  1/DPR;
     arrow.line.material.depthWrite = false;
     arrow.line.material.depthTest = false;
     arrow.cone.material.depthWrite = false;
diff --git a/web/app/3d/wizards/wizards.js b/web/app/3d/wizards/wizards.js
index a9de72d9..2a33f03b 100644
--- a/web/app/3d/wizards/wizards.js
+++ b/web/app/3d/wizards/wizards.js
@@ -2,18 +2,19 @@ import Vector from '../../math/vector'
 import * as cad_utils from '../cad-utils'
 import * as math from '../../math/math'
 import {Matrix3, AXIS, ORIGIN, IDENTITY_BASIS} from '../../math/l3space'
+import DPR from '../../utils/dpr'
 
 
 var IMAGINE_MATERIAL = new THREE.LineBasicMaterial({
   color: 0xFA8072,
-  linewidth: 1/cad_utils.DPR,
+  linewidth: 1/DPR,
   depthWrite: false,
   depthTest: false
 });
 
 var BASE_MATERIAL = new THREE.LineBasicMaterial({
   color: 0x8B0000,
-  linewidth: 3/cad_utils.DPR,
+  linewidth: 3/DPR,
   depthWrite: false,
   depthTest: false
 });
diff --git a/web/app/utils/dpr.js b/web/app/utils/dpr.js
new file mode 100644
index 00000000..70d0cf33
--- /dev/null
+++ b/web/app/utils/dpr.js
@@ -0,0 +1,2 @@
+const DPR = (window.devicePixelRatio) ? window.devicePixelRatio : 1;
+export default DPR;
\ No newline at end of file