* Fix increasing scrolling error of scrollBy by compensation - #1139
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MrRogerHuang wants to merge 22 commits into
Open
* Fix increasing scrolling error of scrollBy by compensation#1139MrRogerHuang wants to merge 22 commits into
MrRogerHuang wants to merge 22 commits into
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…ction with different writing modes.
…-container and iframe for scrollbar.
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Hey! Thank you! It worked for me <3 |
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`scrollBy' in this file
epub.js/src/managers/default/index.js
Line 829 in a1e77b7
operates scrollLeft or scrollTop for moving to previous or next page.
However, the document
https://developer.mozilla.org/en-US/docs/Web/API/Element/scrollLeft
said: "On systems using display scaling, scrollLeft may give you a decimal value."
Thus, operations on scrollLeft or scrollTop could be not precise!
E.g., this.container.scrollTop is 0 and y is 100, after this.container.scrollTop += y, this.container.scrollTop might become 99.xxx!
The worse problem is this error increases with increasing prev() or next(). It can result in this kind of page shift problem:
With the compensation algorithm in this pull request branch, the problem is alleviated!

This compensation algorithm works also for horizontal writing ePub. E.g, the one without compensation:


The one with compensation: