{"action":"created","issue":{"url":"https://api.github.com/repos/phetsims/molecules-and-light/issues/114","labels_url":"https://api.github.com/repos/phetsims/molecules-and-light/issues/114/labels{/name}","comments_url":"https://api.github.com/repos/phetsims/molecules-and-light/issues/114/comments","events_url":"https://api.github.com/repos/phetsims/molecules-and-light/issues/114/events","html_url":"https://github.com/phetsims/molecules-and-light/issues/114","id":72199140,"number":114,"title":"Photon recentering interferes with playback","user":{"login":"samreid","id":679486,"avatar_url":"https://avatars.githubusercontent.com/u/679486?v=3","gravatar_id":"","url":"https://api.github.com/users/samreid","html_url":"https://github.com/samreid","followers_url":"https://api.github.com/users/samreid/followers","following_url":"https://api.github.com/users/samreid/following{/other_user}","gists_url":"https://api.github.com/users/samreid/gists{/gist_id}","starred_url":"https://api.github.com/users/samreid/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/samreid/subscriptions","organizations_url":"https://api.github.com/users/samreid/orgs","repos_url":"https://api.github.com/users/samreid/repos","events_url":"https://api.github.com/users/samreid/events{/privacy}","received_events_url":"https://api.github.com/users/samreid/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":{"login":"jessegreenberg","id":6396244,"avatar_url":"https://avatars.githubusercontent.com/u/6396244?v=3","gravatar_id":"","url":"https://api.github.com/users/jessegreenberg","html_url":"https://github.com/jessegreenberg","followers_url":"https://api.github.com/users/jessegreenberg/followers","following_url":"https://api.github.com/users/jessegreenberg/following{/other_user}","gists_url":"https://api.github.com/users/jessegreenberg/gists{/gist_id}","starred_url":"https://api.github.com/users/jessegreenberg/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/jessegreenberg/subscriptions","organizations_url":"https://api.github.com/users/jessegreenberg/orgs","repos_url":"https://api.github.com/users/jessegreenberg/repos","events_url":"https://api.github.com/users/jessegreenberg/events{/privacy}","received_events_url":"https://api.github.com/users/jessegreenberg/received_events","type":"User","site_admin":false},"milestone":null,"comments":1,"created_at":"2015-04-30T15:42:44Z","updated_at":"2015-04-30T15:43:47Z","closed_at":null,"body":"While instrumenting the sim for tandem, I saw this code in ObservationWindow.js\r\n\r\n```js\r\n// Set up the event listeners for adding and removing photons.\r\nphotonAbsorptionModel.photons.addItemAddedListener( function( addedPhoton ) {\r\n  var photonNode = new PhotonNode( addedPhoton, thisWindow.modelViewTransform );\r\n  photonNode.center = ( modelViewTransform.modelToViewPosition( photonAbsorptionModel.getPhotonEmissionLocation() ) );\r\n  photonLayer.addChild( photonNode );\r\n  //...\r\n}\r\n```\r\n\r\nPhotonNode sets the position by linking to the property, but it is overriden by this line:\r\n```js\r\nphotonNode.center = ( modelViewTransform.modelToViewPosition( photonAbsorptionModel.getPhotonEmissionLocation() ) );\r\n```\r\n\r\nthus preventing loading the positions of photons.  Can that line be eliminated?  I tried removing it and the sim seemed to function properly."},"comment":{"url":"https://api.github.com/repos/phetsims/molecules-and-light/issues/comments/97844932","html_url":"https://github.com/phetsims/molecules-and-light/issues/114#issuecomment-97844932","issue_url":"https://api.github.com/repos/phetsims/molecules-and-light/issues/114","id":97844932,"user":{"login":"samreid","id":679486,"avatar_url":"https://avatars.githubusercontent.com/u/679486?v=3","gravatar_id":"","url":"https://api.github.com/users/samreid","html_url":"https://github.com/samreid","followers_url":"https://api.github.com/users/samreid/followers","following_url":"https://api.github.com/users/samreid/following{/other_user}","gists_url":"https://api.github.com/users/samreid/gists{/gist_id}","starred_url":"https://api.github.com/users/samreid/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/samreid/subscriptions","organizations_url":"https://api.github.com/users/samreid/orgs","repos_url":"https://api.github.com/users/samreid/repos","events_url":"https://api.github.com/users/samreid/events{/privacy}","received_events_url":"https://api.github.com/users/samreid/received_events","type":"User","site_admin":false},"created_at":"2015-04-30T15:43:47Z","updated_at":"2015-04-30T15:43:47Z","body":"I removed the line in question above so that I can proceed with #112 but it would be great to hear from @jessegreenberg if that line was doing something important or if it is okay to be removed."}}