Problem with setInterval

[fbrzvnrnd]

Hi,

I downloaded the 4.9.1 version of Calibre and I have a strange problem with Calibre Reader, EPUB3 and setInterval function in javascript: seems that Calibre reader fails to handle the setInterval function. The events linked to the interval happens in wrong time and does not stop when I use a clearInterval.

Someone could verify this?


Fabrizio

[gbm]

Originally Posted by fbrzvnrnd

Hi,

I downloaded the 4.9.1 version of Calibre and I have a strange problem with Calibre Reader, EPUB3 and setInterval function in javascript: seems that Calibre reader fails to handle the setInterval function. The events linked to the interval happens in wrong time and does not stop when I use a clearInterval.

Someone could verify this?


Fabrizio

Don't use javascript, it is a epub not a program.

bernie

[fbrzvnrnd]

Originally Posted by gbm

Don't use javascript, it is a epub not a program.

bernie

Ok boomer.

[fbrzvnrnd]

(If anyone wants to seriously answer the problem, they are welcome.)

[Bookstooge]

With your response and attitude towards gbm, don't expect much help now.

[theducks]

Originally Posted by Bookstooge

With your response and attitude towards gbm, don't expect much help now.

[BetterRed]

I would have thought bernie was big and ugly enough to take offence for himself.

@gbm, a smiley would have helped - unless you were suggesting EPUB3 does not support javascript in all seriousness.

BR

[Bookstooge]

Originally Posted by BetterRed

I would have thought bernie was big and ugly enough to take offence for himself.

@gbm, a smiley would have helped - unless you were suggesting EPUB3 does not support javascript in all seriousness.

BR

Ok boomer

[DNSB]

I'll worry about calibre book viewer handling embedded Javascript after it starts handling fixed layout epub3. Considering the issues with QT that have been reported such as QT 5.12.1 using a minimum 1 sec resolution, I'm not holding my breath waiting for either.

Out of curiosity, how are you handling the fallbacks for non-scripted renderers?

[fbrzvnrnd]

Originally Posted by Bookstooge

With your response and attitude towards gbm, don't expect much help now.

I'm sorry, but I had written to highlight a Calibre problem thinking that it would be useful for the community to know about it. I found the answer not very contingent, self-referential and - in essence - not useful.

[fbrzvnrnd]

Originally Posted by DNSB

I'll worry about calibre book viewer handling embedded Javascript after it starts handling fixed layout epub3. Considering the issues with QT that have been reported such as QT 5.12.1 using a minimum 1 sec resolution, I'm not holding my breath waiting for either.

Thank you for the answer. I understand. It is strange that older version of Calibre were working fine with it.

Out of curiosity, how are you handling the fallbacks for non-scripted renderers?

The EPUB3 is an ebook of electronic literature (electronic poetry), so non-scripted renderers show "static" poetry. (If you have interest here you can find a video where I present the ebook (in Italian) for a mention received by the Moebius prize a few years ago).

Fabrizio

[davidfor]

Originally Posted by fbrzvnrnd

Thank you for the answer. I understand. It is strange that older version of Calibre were working fine with it.

The issue is that in the past, Javascript was not supported in epubs. The epub3 specs do have some Javascript support. But, it is optional. Not every ereader or app will support it. And some will explicitly not support it. And some effectively only support it by accident (they are basically a wrapper around a browser control and if that control supports Javascript, then the ereader does as well). I don't know where the calibre viewer falls with this.

As such, the reaction was basically an, "avoid Javascript because you don't know if it will work everywhere".

And you left out a very important piece of information in your report. If you used a previous version of calibre and the viewer did support you Javascript, and the current version doesn't, then you should have said so. That would have gotten a very different reaction.

And, I don't know the answer. I would expect the current view to support some Javascript, but, again, I don't know for sure as I don't think I have any books that contain Javascript. And I don't remember any recent discussion on it.

[fbrzvnrnd]

Originally Posted by davidfor

The issue is that in the past, Javascript was not supported in epubs.

Yes, I know. I started one of the first digital publishing house in Italy, uh, 10 years ago, and I manually created a lot of hypertext ePub2.

The epub3 specs do have some Javascript support. But, it is optional. Not every ereader or app will support it. And some will explicitly not support it.

This is true. The EPUB3 specs have javascript support and - yes - IDPF wanted it to be optional. To be honest, I think this was a *big* mistake of IDPF. Now IDPF is "gone" and it seems to me that the w3c specs for Digital Pubblication are going in another direction.

And some effectively only support it by accident (they are basically a wrapper around a browser control and if that control supports Javascript, then the ereader does as well). I don't know where the calibre viewer falls with this.

Yes, but the "new direction" for EPUB is going follow the HTML5 philosophy: if there is support for something, do it. The SVG support in EPUB 3.2, for example, has this kind of view.

As such, the reaction was basically an, "avoid Javascript because you don't know if it will work everywhere".

I believe that if this was the concept that someone wanted to express, he could work on it more. I'm working on electronic literature ebooks, so I have to go to the edge of the specs to show what a digital publication could do. I think we are using the tip of the iceberg in digital publication, and we are losing years of development, and time and money in App that are going to dead after some months or years.

And you left out a very important piece of information in your report. If you used a previous version of calibre and the viewer did support you Javascript, and the current version doesn't, then you should have said so. That would have gotten a very different reaction.

you are right, my fault. English is not my primary language and I had given it as implicit when I mentioned the caliber version, but in fact it wasn't. My fault.

Thank you for the answer.


Fabrizio

[JSWolf]

Originally Posted by fbrzvnrnd

Hi,

I downloaded the 4.9.1 version of Calibre and I have a strange problem with Calibre Reader, EPUB3 and setInterval function in javascript: seems that Calibre reader fails to handle the setInterval function. The events linked to the interval happens in wrong time and does not stop when I use a clearInterval.

Someone could verify this?


Fabrizio

Download the 4.10.1 version of Calibre. The version of QT was updated and that might change how the viewer is working for your case.

[JSWolf]

Originally Posted by fbrzvnrnd

I believe that if this was the concept that someone wanted to express, he could work on it more. I'm working on electronic literature ebooks, so I have to go to the edge of the specs to show what a digital publication could do. I think we are using the tip of the iceberg in digital publication, and we are losing years of development, and time and money in App that are going to dead after some months or years.

The problem is that going to the edge of what of the ePub3.x specs is not a good idea. Most programs that handle ePub do not go there and your eBooks may not work properly. You have to test them in real world cases. On different Readers using different versions of RMSDK such as Sony Readers, Kobo, and others. Also, there are all different versions of ADE being used from 2.0.1 to the current version. Then there are a lot of people using different programs for iOS and Android. And speaking of iOS, even iBooks/Books is out there in different versions that cannot be upgraded. So don't go cutting edge as you'll get a paper cut trying to do so.