diff --git a/script.js b/script.js
index d0db5af6..ad44c8d5 100644
--- a/script.js
+++ b/script.js
@@ -1470,11 +1470,11 @@ canvas.addEventListener('mousedown', e => {
     updatePointerDownData(pointer, -1, posX, posY);
 });
 
-canvas.addEventListener('mousemove', e => {
-    let pointer = pointers[0];
+window.addEventListener('mousemove', e => {
+    //let pointer = pointers[0];
     if (!pointer.down) return;
-    let posX = scaleByPixelRatio(e.offsetX);
-    let posY = scaleByPixelRatio(e.offsetY);
+    let posX = scaleByPixelRatio(e.clientX);
+    let posY = scaleByPixelRatio(e.clientY);
     updatePointerMoveData(pointer, posX, posY);
 });
 
@@ -1539,8 +1539,8 @@ function updatePointerDownData (pointer, id, posX, posY) {
 function updatePointerMoveData (pointer, posX, posY) {
     pointer.prevTexcoordX = pointer.texcoordX;
     pointer.prevTexcoordY = pointer.texcoordY;
-    pointer.texcoordX = posX / canvas.width;
-    pointer.texcoordY = 1.0 - posY / canvas.height;
+    pointer.texcoordX = posX / (window.width/2);
+    pointer.texcoordY = 1.0 - posY / (window.height/2);
     pointer.deltaX = correctDeltaX(pointer.texcoordX - pointer.prevTexcoordX);
     pointer.deltaY = correctDeltaY(pointer.texcoordY - pointer.prevTexcoordY);
     pointer.moved = Math.abs(pointer.deltaX) > 0 || Math.abs(pointer.deltaY) > 0;