Auto zoom landscape documents (like slide presentations) to fit their height

[cpeterso]

Landscape documents, like slide presentations, are much easier to read if "Automatic Zoom" fits the slide height so the full slide is visible. Here is an example landscape slide presentation:

https://wiki.mozilla.org/images/5/55/MobileOpportunity.pdf

[Snuffleupagus]

/botio-windows preview

[pdfjsbot]

From: Bot.io (Windows)

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[pdfjsbot]

From: Bot.io (Windows)

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Success

Full output at http://107.22.172.223:8877/db7c04723fd266e/output.txt

Total script time: 0.89 mins

Published

• Viewer: http://107.22.172.223:8877/db7c04723fd266e/web/viewer.html
• B2G Viewer: http://107.22.172.223:8877/db7c04723fd266e/extensions/b2g/content/web/viewer.html
• Extension: http://107.22.172.223:8877/db7c04723fd266e/extensions/firefox/pdf.js.xpi
• Extension (AMO): http://107.22.172.223:8877/db7c04723fd266e/extensions/firefox/pdf.js.amo.xpi

[Snuffleupagus]

Personally, I don't think this change is good for most documents.
For landscape documents, this is obviously better. However most documents are in portrait mode, where this change, in my opinion, negatively impacts the initial display of the document. (Look for example at the default tracemonkey.pdf file.)
With this patch, I would have to change the zoom level before being able to comfortably read documents in portrait mode.

Could we perhaps use different behaviours for "Auto zoom" depending on the page orientation, or would that be too confusing?

Edit: Since this patch is basically about setting "Page fit" as the default zoom level for most documents, we could perhaps instead add a keyboard shortcut for "Page fit". This was recently requested in #5206.

[cpeterso]

@Snuffleupagus: oops! I did not intend to change the portrait mode, so I will fix that. My initial fix tested for landscape documents (with currentPage.width > currentPage.height), but I then, apparently, tried to be too clever. <:)

[cpeterso]

@Snuffleupagus: I fixed this PR so the portrait mode is unaffected and landscape mode scale to fix the height of the page.

[Snuffleupagus]

/botio-linux preview

[pdfjsbot]

From: Bot.io (Linux)

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Command cmd_preview from @Snuffleupagus received. Current queue size: 0

Live output at: http://107.21.233.14:8877/9a0840675191590/output.txt

[pdfjsbot]

From: Bot.io (Linux)

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Full output at http://107.21.233.14:8877/9a0840675191590/output.txt

Total script time: 0.77 mins

Published

• Viewer: http://107.21.233.14:8877/9a0840675191590/web/viewer.html
• B2G Viewer: http://107.21.233.14:8877/9a0840675191590/extensions/b2g/content/web/viewer.html
• Extension: http://107.21.233.14:8877/9a0840675191590/extensions/firefox/pdf.js.xpi
• Extension (AMO): http://107.21.233.14:8877/9a0840675191590/extensions/firefox/pdf.js.amo.xpi

[Snuffleupagus]

This looks much better to me!
@yurydelendik What's your opinion about this PR?

/botio-linux lint

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From: Bot.io (Linux)

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Command cmd_lint from @Snuffleupagus received. Current queue size: 0

Live output at: http://107.21.233.14:8877/8b496a65e94919f/output.txt

[pdfjsbot]

From: Bot.io (Linux)

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Success

Full output at http://107.21.233.14:8877/8b496a65e94919f/output.txt

Total script time: 1.84 mins

• Lint: Passed

[cpeterso]

I think the Travis build errors are unrelated to my code changes. Travis is complaining that it can't clone the git repo git://git.code.sf.net/p/fonttools/code.

[timvandermeij]

You're right, it's Travis' fault. Our own lint check succeeded.

[yurydelendik]

Thank you for the patch