unwarranted limit to magnification

When I paste the drawing below into MarvinSketch applet here, I can magnify a bit (using the magnifying glass + tool on the toolbar), but then it stops magnifying. I don't see this problem in the desktop version. I've had this problem with other large drawings as well. There's no reason to stop magnifying.

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Dear Bob,

I could not reproduce this issue. I could scale up the drawing to a very large scale with the tool on the toolbar. Which Java version running when the problem occurs?

Regards,
István 

Darn it with the irreproducible problems! I just updated OS 10.9 and Safari on my desktop, maybe that made the difference. I'll let you know if it happens again.

Interesting! I can reproduce it on my MacBook Air, but not on my MacMini! Both are running OS 10.9.5. The MacBook Air is running Java 1.6.0_65, whereas the MacMini is running Java 1.7.0_25 (information from "java -version"). Maybe that's the difference. I don't know why the MacBook Air hasn't downloaded Java 1.7.

Stranger and stranger. On my MacBook Air, when I go to the Oracle Java site, it tells me I have Java 1.7 version 67. And when I go to my Java control panel, it tells me the same thing. But when I type java -version, it tells me I have only Java 1.6.0_65. ??

Dear Bob,

On Mac the browser pugin and the JRE can make strange things like that. I think you can trust the Verify Java result when you want to find out the java version for your applets, and the java -version result for your desktop application.

Regards,
István 

OK, but that still doesn't explain why on my MacBook Air, the MarvinSketch applet won't allow me to magnify the drawing more than a couple of times.

Hi Bob,

the maximum zoom level is 6400%, in the drop-down the maximum value is 400%

the minimum level of zoom is 1%.

These are the only limitations we have built in, we can not really say more about this issue, should we check it more deeply? I am skeptical a bit possibly but I am afraid we will not be able to find out what causes the difference, since in the code level there are not any more restrictions besides the aforementioned ones.

Regards,
Istvan 

Following the instructions I gave above, I still see this problem with MarvinSketch 15.2.2.0, Safari 8.03, OS 10.10.2, MacBook Air (13-inch, mid 2013).

Hi Bob,

We managed to reproduce this bug. It was connected to the MacBook's retina resolution.

The fix will be available next week.

Best regards,

Peter

Oh, of course, the retina resolution! Why didn't I think of that?

Thanks for looking into it. The bug really was inhibiting my ability to examine students' responses.

We haven't thought of it either and after we could not reproduce this on our mac mini with a 1080p monitor. :)

We decided to buy a MacBook Pro and I will continue the development and testing of Marvin on this to prepare us for the strange behavior can appear on this system.

Hopefully you won't hit any Mac-specific issue in the future. I can't guarantee that you won't hit any other issue though :)

 

BRs

Peter