Problems with zoom.it display (noise/residual imagery when initially rendering image)

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  • Updated 7 years ago


Hi everyone! I've noticed in the past several days that most/all of the zoom.it images I use to show samples of maps on our website have started to malfunction just a bit. An example of what is occurring is above. The zoom.it interface starts displaying the image, but then as it reduces the size of the image a bit (at first rendering), it is leaving a lot of "noise" on the left edge of the display. It's happening on most/all pages, though the page in this specific case is: http://www.mapformation.com/portfolio...

The only thing that has changed on my local computer since the problem began to rear its ugly head is that I disabled Java in my browser (Google Chrome). Is Java needed to dispay the zoom.it interface properly, or might something else be going on? Just curious. That would be nice...if it's "just me" that is seeing this weirdness. Thanks for the help! - Derek
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Derek Tonn

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  • concerned

Posted 7 years ago

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Bill Crow, Seadragon Group Manager

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It's a strange problem, Derek, but it appears to be an issue with Chrome.

I can duplicate your problem, but only with Chrome and only with the embed on your web page. There is no problem if you click the full screen button. It also works just fine in Internet Explorer in all display modes, with either Silverlight or JavaScript. It also works with no problem in Safari. Whatever is going on here, it's specific to Chrome.

Another strange data point is that your image displays just fine in Chrome on the zoom.it website, which is using the same embed: http://zoom.it/mqSy

So, my best guess is that a recent Chrome update has caused a regression. Presumably it previously worked in Chrome. It works fine with the other major browsers. So, this should be pursued with Google to figure out what they changed that caused this regression.

Since it does work in full-screen mode and on the zoom.it site, its possible you could find an interim work-around. One hypothesis is that is that there is some CSS or other attribute on your page that might be inadvertently tweaking Chrome in some way that is causing this incorrect rendering behavior with the zoom.it embed.

Have there been other recent changes to this page on your site? Is it possible for you to construct a new, clean-and-simple page that only includes the embed and see if that works? If so, then its a game of "process of elimination" to figure out exactly what element on your page is annoying Chrome and causing the incorrect behavior. That could serve as both a workaround for you as well as useful data for Google to debug what's going on with Chrome.

Zoom.it does not use Java in any way, so I doubt that change was a factor. You could always re-enable Java for a test, just to be sure its not effecting something in Chrome related to this rendering problem.

Hope this helped!
Bill Crow
(former) Seadragon Group Manager
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Aseem Kishore, Former Employee

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Great answer, Bill!
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caseywood

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I'm also having this problem. See the page I'm developing here: http://www.caseywood.net/ . A couple of points to add, I'm only encountering this with Chrome (as mentioned above) and only when the browser window is maximized. If the browser is not maximized, this problem doesn't exist.

Edit: I should also mention mine is a wordpress site.
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Nathanael Lawrence

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@Derek Tonn and @caseywood, do either of you encounter the same bug with the Canvas Zoom demo?

I know that Live Labs and the Seadragon group are long since disbanded, but I also know that Aseem maintains a mirror of the Seadragon AJAX source on GitHub. Perhaps it could be updated to reflect the changes in the Canvas Zoom viewer if there is any true advantage to that?

I thought that I remembered Aseem saying before that zoom.it already utilized Canvas in browsers that supported it, so perhaps I'm suggesting nonsense, but if Derek and Casey would take the time to test the alternate viewer to see whether the bug is resolved there, I'd appreciate it.

I know it's a big ask on my part, but if Aseem had the time and inclination to do this update for the GitHub check-in, perhaps someone would be so kind as to post those changes to zoom.it as well?
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caseywood

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I don't encounter the same problem in the Canvas Zoom demo you linked, but I also don't encounter the same problem here http://zoom.it/Ufke , which is the same graph from my website I linked in my previous post. Full screen doesn't seem to present the same issue.
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Derek Tonn

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@Nathanael: If it helps, I do not encounter the same issue (in Google Chrome) on the Canvas Zoom demo.
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caseywood

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I should mention I've changed my wordpress theme since my original post, and now the problem is not noise, but rather that I can see squares outlined in my picture.