{"action":"opened","issue":{"url":"https://api.github.com/repos/catapult-project/catapult/issues/1865","labels_url":"https://api.github.com/repos/catapult-project/catapult/issues/1865/labels{/name}","comments_url":"https://api.github.com/repos/catapult-project/catapult/issues/1865/comments","events_url":"https://api.github.com/repos/catapult-project/catapult/issues/1865/events","html_url":"https://github.com/catapult-project/catapult/issues/1865","id":123390870,"number":1865,"title":"Visual glitches in event boundaries at high zoom levels in Trace-Viewer","user":{"login":"benthaman","id":254681,"avatar_url":"https://avatars.githubusercontent.com/u/254681?v=3","gravatar_id":"","url":"https://api.github.com/users/benthaman","html_url":"https://github.com/benthaman","followers_url":"https://api.github.com/users/benthaman/followers","following_url":"https://api.github.com/users/benthaman/following{/other_user}","gists_url":"https://api.github.com/users/benthaman/gists{/gist_id}","starred_url":"https://api.github.com/users/benthaman/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/benthaman/subscriptions","organizations_url":"https://api.github.com/users/benthaman/orgs","repos_url":"https://api.github.com/users/benthaman/repos","events_url":"https://api.github.com/users/benthaman/events{/privacy}","received_events_url":"https://api.github.com/users/benthaman/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":0,"created_at":"2015-12-22T01:09:41Z","updated_at":"2015-12-22T01:09:41Z","closed_at":null,"body":"I've noticed three bugs that appear around the boundaries of events at high zoom levels. I'm reporting as one issue only since I guess that they all stem from the same miscalculation (rounding errors?) of event boundaries.\r\n\r\nThe glitches are demonstrated in the following video:\r\nhttp://beta.suse.com/private/bpoirier/tv-bug/mini.mp4\r\nTimes between brackets below refer to the video.\r\n\r\n1. When panning, the time scale and tick marks move fluidly but event boundaries jump. [00:00-00:23]\r\n2. When zooming in, event boundaries jump. [00:24-00:35]\r\n3. When selecting, the selection box may be over the end of an event (as it is displayed) but the resulting selection does not include the event. Conversely, the selection box may not be over the end of an event but the resulting selection includes the event. [00:41-00:53]\r\n\r\nThe impact of these problems is made worse by the fact that the drawing errors are not the same for two events that have a different start time but a duration such that the two events have the same end time. The two events used to demonstrate the glitches in the previous video have the following properties:\r\n\r\n    start 5609.031ms\r\n    duration 1572.869ms\r\n    \r\n    start 5609.037ms\r\n    duration 1572.863ms\r\n\r\nHence they end at the same time and should be displayed as such. This is what initially tipped me off to these problems.\r\n\r\nThe trace data is available here\r\nhttp://beta.suse.com/private/bpoirier/tv-bug/mini.json\r\n\r\nIt was exported to html using trace2html from git 417f85b\r\nhttp://beta.suse.com/private/bpoirier/tv-bug/mini.html\r\n\r\n\r\n\r\n\r\n"}}