Update script.js

script.js

-MIT License
-
-Copyright (c) 2020 Jiyoung Moon
-
-Permission is hereby granted, free of charge, to any person obtaining a copy
-of this software and associated documentation files (the "Software"), to deal
-in the Software without restriction, including without limitation the rights
-to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-copies of the Software, and to permit persons to whom the Software is
-furnished to do so, subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.
-
 var gl;
 
 var shaderProgram;
@@ -37,7 +15,6 @@ function initialStep(canvas) {
     catch (e) {
     }
     
-    ////// new code!
     var drag=false;
 
     var original_x, original_y;
@@ -45,10 +22,10 @@ function initialStep(canvas) {
     var Downward=function(e) {
 
         drag=true;
-        original_x=e.pageX, original_y=e.pageY;
+        original_x = e.pageX;
+        original_y = e.pageY;
         e.preventDefault();
 
-        return false;
     };
 
     var Upward=function(e){
@@ -56,13 +33,14 @@ function initialStep(canvas) {
     };
 
     var Moving=function(e) {
-        if (drag==false) return false;
+        if (!drag) return false;
         
         var gap_x = e.pageX - original_x;
         var gap_y = e.pageY - original_y;
         
-        y_rad += gap_x*2*Math.PI/canvas.width;
-        x_rad += gap_y*2*Math.PI/canvas.height;
+        y_rad += gap_x*3/canvas.width;
+        x_rad += gap_y*3/canvas.height;
+
         original_x = e.pageX;
         original_y = e.pageY;
 
@@ -71,8 +49,8 @@ function initialStep(canvas) {
 
     canvas.addEventListener("mousedown", Downward, false);
     canvas.addEventListener("mouseup", Upward, false);
+    canvas.addEventListener("mouseout", Upward, false);
     canvas.addEventListener("mousemove", Moving, false);
-    //////
 
 }