Fix rotatable objects rotation when y velocity is zero, see #137

phetsims · Aug 11, 2017 · 9d8d243 · 9d8d243
1 parent 657fe95
commit 9d8d243
Showing 1 changed file with 6 additions and 2 deletions.
diff --git a/js/common/view/ProjectileNode.js b/js/common/view/ProjectileNode.js
@@ -197,8 +197,12 @@ define( function( require ) {
 
       // only rotate the object if it doesn't have an assigned benchmark, or it is an object that rotates
       if ( objectType ? objectType.rotates : true ) {
-        var angle = Math.atan( dataPoint.velocity.y / dataPoint.velocity.x ) ||
-          ( dataPoint.velocity.y > 0 ? Math.PI / 2 : 3 * Math.PI / 2 );
+        if ( dataPoint.velocity.x ) { // if x velocity is not zero
+          var angle = Math.atan( dataPoint.velocity.y / dataPoint.velocity.x );
+        }
+        else { // x velocity is zero
+          angle = dataPoint.velocity.y > 0 ? Math.PI / 2 : 3 * Math.PI / 2;
+        }
         projectileObjectView.setRotation( -angle );
       }