Scroll smoothly with mouse wheel

[djlewis]

I gather from other threads that, in the Calibre viewer, getting the mouse wheel to scroll only one line at a time is problematic. In fact, I see that the mouse wheel scrolls several lines in my browser.

But it would help a whole lot if, like the browser, the lines scrolled smoothly rather than jumping discretely.

With jumping lines, it is very difficult to scan through some text. The eye/mind cannot coherently follow big, discrete jumps (7 or so lines with my current system, mouse and driver) -- I get constantly disoriented, which defeats the purpose of scanning. My workaround is to use the up and down arrow keys, which do scroll smoothly, but that means shifting my hand back and forth between mouse and keyboard, and also using two different keys.

So, if there is no such option (I can't find one), may I request smooth mouse wheel scrolling as a feature.

Thanks. --David

[theducks]

The number of lines using the scroll wheel is typically a Mouse driver (control panel) setting

[djlewis]

OK, I changed the mouse wheel setting (in the control panel) from 3 lines to 1. But no change in Calibre viewer behavior -- the wheel still scrolls 7 lines at a time, and more to the point, it's a discrete jump of all 7 lines.

Still seems to me that the easiest (I am guessing) solution is to make the scrolling smooth rather than discrete, whatever the number of lines.

[theducks]

Weird
I see 5 lines (of the spreadsheet) on W7 with no setting change.
Same in the book editor.
I only use the Viewer for quick peeks at the contents, I read on my devices.

[kovidgoyal]

Patches are welcome. Note that viewer is optimized for page by page viewing and with default setting the mouse wheel flips pages, not lines.

[djlewis]

I do the majority of my ebook reading on a Windows PC. Actually a lot of it is not reading from cover to cover, but searching and reading specific parts of various works for research purposes. Thus, the Calibre viewer is important for me because it's much better at searching, extracting and printing portions than Kindle for Windows, and it has continuous scroll mode as an option to the very annoying page-flip mode -- a disastrous mimicking of physical media, IMHO.

But the mouse scroll wheel is barely usable because of its 7-line discrete jump, as I explain above. I understand the issues with getting it to scroll by single lines, but making it scroll smoothly (and perhaps in smaller increments than 7 lines) would be fine.

I realize mine is probably not a common usage pattern, but it still seems to me that smooth scrolling is a reasonable expectation for a reading application.

Are you saying it can be implemented by a patch to Calibre? I was a professional programmer in the past, though not so much for a few years, and might be willing to tackle it. But I already have too many tool-based projects distracting me from my actual research, so I am reluctant.

Regards. --David

[kovidgoyal]

Yes, it can be implemented as a patch. calibre is open source, feel free to make whatever changes you like to suit your workflow. http://manual.calibre-ebook.com/develop.html

I will note that no browser I posses does smooth scrolling on mouse wheel motion either. And personally, I would find the notion of smooth scrolling by mouse wheel completely unusable, it would just make scrolling slow and aggravating.

[BetterRed]

@djlewis - You could try Firefox 28 + EPUBReader 1.4.2.4. They give me what I think of as smooth scrolling via mouse wheel. you'll need to change its settings to a vertical web-like style. You might want to adjust you mouse settings, mine's set to 4 - gets a bit laggy if its higher, and jerky if its lower. I don't think I did any special changes to Firefox settings via Options or about:config.

It took Mozilla quite a few years to get smooth scrolling via mouse wheel working properly, cant recall when they finally cracked it - within the last couple of years I would think.

Be aware that EPUBReader will store a copy of anything you read into in the firefox profile - ie it creates yet another ebook library Ψ

BR

[kovidgoyal]

Oh and the code you will want to modify is in documentview.py look for wheelEvent

[djlewis]

Thanks. EPUBReader works nicely with the mouse wheel. I'll use it when I have a lot of pc-based reading to do.

Also, thanks for the pointer to the code. Looks quite do-able, though I'm not sure I could crack the mysteries of smooth scrolling, even if I were to fire up an environment and start working with py -- I'm more of a ruby guy.

I do note that Firefox (and therefore ePUBReader) does scroll 3-4 lines at a time with the wheel, but does so continuously rather than in one gulp, and in such a way that gulps run together nicely for sequences of scrolls. That seems to be the trick.

I'll probably put this on the official wish-list for Calibre -- seems like a legitimate feature request.

Love Calibre, by the way -- terrific job! Don't know where I'd be without it -- tearing out my hair over Kindle, most likely.

Thanks.

[tazztone]

hello
apart from smooth scrolling by mouse wheel i also miss the "middle-click and moving the cursor down" for smooth scrolling. i also like reading the books in continuous flow mode (like websites)

this is still not possible with calibre right?