The PDF Viewer's preset zoom levels match those of the browser.

I have a feeling we have more detailed content in some cases then webpages. It maybe worthwhile adding extra zoom to see how it works. I don't think we have to exactly match the browser in this case.

So there is a UX question here, and in  bug 715670 , for how much we want the PDF Viewer to behave like other tabs that render HTML / other Blink-rendered content.

e.g. For users that do not understand the distinction between HTML and PDF, how would they feel if some tabs can be zoomed to 6400%, and other can only be zoomed to 500% ?

We already do have a distinction between PDF and HTML in that PDF has a whole bunch of controls that HTML doesn't. The zoom mechanism has the buttons at the bottom, the toolbar, etc.

dsinclair, who would be correct person to take ownership of the meta-issue here, of how much the PDF viewer should be have like a webpage?

In response to #3, I can't picture this difference between webpages and PDFs actually getting in the way of users.

We'll probably need to talk to someone from UX about this. Assigning to hnakashima@ for ProductExcellence. I'm guessing we'll have a few things under PE that will require UI/UX so if we can group them together that would probably be best.

Note that if we introduce preset zoom factors only in the viewer, it would cause issues.

The browser's zoom controls (ctrl-+/- and in the menu) would only zoom to the presets it knows about (see zoom::PageZoom::Zoom), so you would have zoom levels only accessible via the viewer's controls.

Also, the browser's presets are currently used to determine the width of the label in the zoom bubble (see ZoomValue::GetLabelMaxWidth).

Deleted: zoom bubble 999.png 8.8 KB

	zoom bubble 999.png 8.8 KB View Download

Deleted: zoom bubble 1000.png 8.7 KB

	zoom bubble 1000.png 8.7 KB View Download

FWIW, the PDF Viewer can already go to zoom levels not in the preset, via fit-to-{page,width}. Maybe we want to update the zoom bubble to support displaying 4-digit zoom levels anyway.

Issue 807526 has been merged into this issue.