Use full screen width in presentation mode

[fkaelberer]

Fixes #4439 by removing all horizontal borders and reducing the vertical ones when in presentation mode.
This improves reading on small devices.

It still looks a little bit awkward that the document is tied to the top of the screen on portrait mode displays, but I didn't figure out how to correctly center it.

[Snuffleupagus]

/botio-windows preview

[pdfjsbot]

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• Viewer: http://107.22.172.223:8877/f4449dbbc16c8c5/web/viewer.html
• B2G Viewer: http://107.22.172.223:8877/f4449dbbc16c8c5/extensions/b2g/content/web/viewer.html
• Extension: http://107.22.172.223:8877/f4449dbbc16c8c5/extensions/firefox/pdf.js.xpi
• Extension (AMO): http://107.22.172.223:8877/f4449dbbc16c8c5/extensions/firefox/pdf.js.amo.xpi

[fkaelberer]

By the way: Is it correct that SCROLLBAR_PADDING is used in
https://github.com/mozilla/pdf.js/blob/master/web/page_view.js#L392?
The code in https://github.com/mozilla/pdf.js/blob/master/web/viewer.js#L288, seems to perform similar calculations, but uses VERTICAL_PADDING instead.
I was just wondering, so ignore this comment if everything is correct.

[Snuffleupagus]

There seems to be an issue with the previous zoom level not getting set correctly with this patch, when exiting presentation while viewing a file with varying page sizes.

A file to reproduce the issue with: http://www.pdfsharp.net/wiki/%28S%28gxgrd055sfetvh55lp5jya55%29%29/GetFile.aspx?File=%2FPageSizes-sample%2FPageSizes_output.pdf.

[fkaelberer]

Can you be more precise on the steps to reproduce?

Some problems were there already, so I don't know if my patch is the cause.

1. Open http://www.pdfsharp.net/wiki/%28S%28gxgrd055sfetvh55lp5jya55%29%29/GetFile.aspx?File=%2FPageSizes-sample%2FPageSizes_output.pdf#page=18
   Result: Page 36 is shown (B5 landscape)
2. Now zoom out using the - mouse button or Ctrl+-.
   Result: Page 17 is shown (RA2), pages are not horizontally centered, but ragged right.

[fkaelberer]

Another issue:
0. Open Firefox and maximize Windows size.

1. Open http://www.pdfsharp.net/wiki/%28S%28gxgrd055sfetvh55lp5jya55%29%29/GetFile.aspx?File=%2FPageSizes-sample%2FPageSizes_output.pdf&AspxAutoDetectCookieSupport=1#page=20&zoom=2
   Result: There seems to be a refresh loop and the spin wheel keeps appearing and disappearing on all pages. Constant CPU load.
   If the problem does not appear, try scrolling to a different part of the document.
2. Reduce the Firefox window size to half-screen height.
   Result: Rendering finishes normally.

The issue appears also in Chrome.

[Snuffleupagus]

Can you be more precise on the steps to reproduce?

The issue I described should by fixed if you make the following changes:

diff --git a/web/presentation_mode.js b/web/presentation_mode.js
index d7c5d29..6a233d3 100644
--- a/web/presentation_mode.js
+++ b/web/presentation_mode.js
@@ -143,6 +143,7 @@ var PresentationMode = {
   },

   exit: function presentationModeExit() {
+    this.active = false;
     var page = PDFView.page;

     // Ensure that the correct page is scrolled into view when exiting
@@ -151,9 +152,6 @@ var PresentationMode = {
     setTimeout(function exitPresentationModeTimeout() {
       PDFView.setScale(this.args.previousScale);
       PDFView.page = page;
-      // Keep Presentation Mode active until the page is scrolled into view,
-      // to prevent issues in non-Mozilla browsers.
-      this.active = false;
       this.args = null;
     }.bind(this), 0);

I think that change should be OK, given that PR #4292 restored the old (properly working) behaviour.

Result: Page 36 is shown (B5 landscape)
2. Now zoom out using the - mouse button or Ctrl+-.
Result: Page 17 is shown (RA2)

This sounds like a duplicate of #3949, and is caused by the fact that the pages all have very different sizes.

pages are not horizontally centered, but ragged right.

Sounds like a duplicate of #4186, patch has been submitted in #4188.

Another issue:
0. Open Firefox and maximize Windows size.
...

Probably not related to this issue, so I wouldn't worry about that here.
Also, zoom == 2, that's a very tiny zoom value.

[fkaelberer]

Thank you for the suggestions.

[fkaelberer]

After thinking about this some more, it might be better to move this line down

Done. Thank you for thinking.

[yurydelendik]

/botio-linux preview

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Published

• Viewer: http://107.21.233.14:8877/3797b4e182e5fa7/web/viewer.html
• B2G Viewer: http://107.21.233.14:8877/3797b4e182e5fa7/extensions/b2g/content/web/viewer.html
• Extension: http://107.21.233.14:8877/3797b4e182e5fa7/extensions/firefox/pdf.js.xpi
• Extension (AMO): http://107.21.233.14:8877/3797b4e182e5fa7/extensions/firefox/pdf.js.amo.xpi

[yurydelendik]

Thank you