Continuous Scrolled reading mode causes page to scroll inconsistently and has a lot of blinking.

[Taum]

When using the continuous scroll mode, we are having issues where the scrolling is inconsistent and the page seems to blink and scroll unexpectedly.

We have filmed our iPad (iPad Air 2) to demonstrate the problem, you can see the video here: http://bayard.tobostudio.com/video/readium.mp4 In this video we load the Moby Dick ePub included as an example in this repository. We have seen the same issues with our own ePubs.

I have tried both the develop branch and the wkwebview feature branch but they both seem to yield comparable results.

Does anyone have suggestions on what should be done to improve this reading mode?

Regards, Thomas

[danielweck]

Thanks for reporting this, and for taking the time to create a screencast. Could you please try the same EPUB on your iPad using Mobile Safari, and let us know if the symptoms are the same? http://readium-cloudreader.divshot.io/

[rkwright]

I wonder if this is some artifact or result of the lazy loading of the chapters?

[danielweck]

I saw some rendering flicker in past tests, more like surface compositing issues than HTML scroll-related problems. But of course we have to check that the iframe heights stabilise correctly once documents are loaded (and fully rendered), and that the scrolling viewport offset remains fixed whilst the pool of HTML documents loads in the "background" (above and below the visible document, within the vertical stack of iframes).

[Taum]

Thank you for your answers. Yes, MobileSafari using http://readium-cloudreader.divshot.io/ seem to have the same problem. I tried the Moby Dick and Page Blanche samples.