From 76f15827572d0ddeaffe4e78d353bf014f4cf946 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Mon, 13 Apr 2015 14:09:59 +0530
Subject: [PATCH] E-book viewer: When displaying multiple pages per screen fix
 whole screen scrolling so that it works as expected even at the end of the
 file, when their might be fewer pages left than would fill the screen.

---
 resources/compiled_coffeescript.zip         | Bin 102835 -> 103952 bytes
 src/calibre/ebooks/oeb/display/paged.coffee |  23 ++++++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/resources/compiled_coffeescript.zip b/resources/compiled_coffeescript.zip
index 9524eb8797154eac87eb0ccd029d13fef25e330a..c0b8d2e5b1bda00269aac2123a94ad24a25ad85f 100644
GIT binary patch
delta 1009
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z%ac?IE|8rvOwkAGj`&BAKb4T;(O7(FctGTbxj{}6Bt9{ah;cCqi=r@yhd7B7VhR89
EUrRelPXGV_

delta 302
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TIX97Oy5VG~r66~kGS&hBOFeDJ

diff --git a/src/calibre/ebooks/oeb/display/paged.coffee b/src/calibre/ebooks/oeb/display/paged.coffee
index c6b762b519..b9509d6dfd 100644
--- a/src/calibre/ebooks/oeb/display/paged.coffee
+++ b/src/calibre/ebooks/oeb/display/paged.coffee
@@ -32,6 +32,19 @@ has_start_text = (elem) ->
             return true
     return false
 
+create_page_div = (elem) ->
+    div = document.createElement('div')
+    div.innerText = ' \n    '
+    div.setAttribute('data-calibre-dummy-page', '1')
+    document.body.appendChild(div)
+    div.style.setProperty('-webkit-column-break-before', 'always')
+    div.style.setProperty('white-space', 'pre')
+    div.style.setProperty('background-color', 'transparent')
+    div.style.setProperty('background-image', 'none')
+    div.style.setProperty('border-width', '0')
+    div.style.setProperty('float', 'none')
+    div.style.setProperty('position', 'static')
+
 class PagedDisplay
     # This class is a namespace to expose functions via the
     # window.paged_display object. The most important functions are:
@@ -125,6 +138,11 @@ class PagedDisplay
             single_screen = (document.body.scrollHeight < window.innerHeight + 75)
             this.handle_rtl_body(body_style)
             first_layout = true
+            if not single_screen and this.cols_per_screen > 1
+                num = this.cols_per_screen - 1
+                while num > 0
+                    num -= 1
+                    create_page_div()
 
         ww = window.innerWidth
 
@@ -434,6 +452,11 @@ class PagedDisplay
             return -1
         cc = this.current_column_location()
         ans = cc + this.screen_width
+        if this.cols_per_screen > 1
+            width_left = document.body.scrollWidth - (window.pageXOffset + window.innerWidth)
+            pages_left = width_left / this.page_width
+            if pages_left < this.cols_per_screen
+                return -1  # Only blank, dummy pages left
         limit = document.body.scrollWidth - window.innerWidth
         if ans > limit
             ans = if window.pageXOffset < limit then limit else -1