node-scroll-info's .getOnscreenNodes uses bad coordinates

[tivac]

Bug is in 3.10.1 & earlier versions, presumably.

.getOnscreenNodes() uses Y.DOM.getXY() to get the position of each node, which is in page coordinates. It's compared against the plugin's _lastScroll property which is in container-relative coordinates. It ends up working sometimes, but not always. I'm not 100% sure why.

http://jsbin.com/exekux/4/edit shows the practical implications of this bug, some images just never get triggered.

Talked with @rgrove about this in IRC & it sounded like he was volunteering to fix it.

[16:39] <@rgrove> It's the Y.DOM.getXY() call in getOnscreenNodes(). DOM.getXY() returns a viewport-relative position, but it's compared with a container-relative position, which is invalid.
[16:40] <@rgrove> Coincidentally, the fix is to use getBoundingClientRect(), which I want to do anyway!

[tivac]

https://gist.github.com/tivac/5616180

has a lazy-loading plugin which provides a fixed version of .getOnscreenNodes() that would almost drop-in to node-scroll-info.

[rgrove]

Weird. GitHub caught the commit that fixed this, but didn't close the issue. Anyway, this is fixed.