nxcomp: Set TokenSize to 1536 for link type ADSL and WAN.

Improving non-xrender based browser scrolling behaviour when link type
is set to ADSL or WAN.

Backported from Arctica GH 3.6.x branch.

v2: backport to nx-libs 3.5.0.x (Mihai Moldovan)

Adds:
  - debian/patches/1300_nxcomp_Set-TokenSize-to-1536-for-lin.full+lite.patch

3 files changed, 71 insertions, 0 deletions

diff --git a/debian/changelog b/debian/changelog
index 4e1e6a7d6..026f8d845 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -63,6 +63,15 @@ nx-libs (2:3.5.0.33-0x2go1) UNRELEASED; urgency=low
     Adds:
     - 1270_nx-X11_CVE-2017-2624-Use-timingsafe_memcmp-to-c.full.patch
 
+  [ Oleksandr Shneyder ]
+  * nxcomp: Set TokenSize to 1536 for link type ADSL and WAN.
+    Improving non-xrender based browser scrolling behaviour when link type is
+    set to ADSL or WAN.
+    Backported from Arctica GH 3.6.x branch.
+    v2: backport to nx-libs 3.5.0.x (Mihai Moldovan)
+    Adds:
+    - debian/patches/1300_nxcomp_Set-TokenSize-to-1536-for-lin.full+lite.patch
+
  -- X2Go Release Manager <git-admin@x2go.org>  Sat, 04 Jul 2015 06:29:19 +0200
 
 nx-libs (2:3.5.0.32-0x2go1) unstable; urgency=low
diff --git a/debian/patches/1300_nxcomp_Set-TokenSize-to-1536-for-lin.full+lite.patch b/debian/patches/1300_nxcomp_Set-TokenSize-to-1536-for-lin.full+lite.patch
new file mode 100644
index 000000000..0baf27058
--- /dev/null
+++ b/debian/patches/1300_nxcomp_Set-TokenSize-to-1536-for-lin.full+lite.patch
@@ -0,0 +1,61 @@
+From 7d51cb6760b760768aeb91dd81f10443d094bd6c Mon Sep 17 00:00:00 2001
+From: Oleksandr Shneyder <o.schneyder@phoca-gmbh.de>
+Date: Thu, 29 Jun 2017 10:08:56 +0200
+Subject: [PATCH] nxcomp: Set TokenSize to 1536 for link type ADSL and WAN.
+ Improving non-xrender based  browser scrolling behaviour when link type is
+ set to ADSL or WAN.
+
+ In the 40-ies (talking about release version numbers), Firefox started
+ using the Skia library [1] for client-side rendering of browser content.
+
+ With current versions of Firefox you can switch between libXrender based
+ rendering (esp. of Fonts) and Skia based rendering:
+
+    gfx.xrender.enabled = true|false
+
+ Some time around Firefox 52, the default for the gfx.xrender.enabled
+ setting got changed by Firefox upstream from true to false. So nowadays,
+ Firefox uses Skia by default.
+
+ However, it turns out that Skia scales really badly on remote X11
+ connections. Scrolling of long web pages becomes really jolty.
+
+ Something similar could be observed earlier already when using
+ Chrome or Chromium (which also has been using Skia for some time
+ now).
+
+ This change in nxcomp works around those issues and greatly
+ improves scrolling and general browser experience on medium
+ throughput networks (like cable modem, ADSL, HDSPA, slow LTE).
+
+ [1] https://en.wikipedia.org/wiki/Skia_Graphics_Engine
+
+ Fixes ArcticaProject/nx-libs#443.
+
+ Backported from Arctica GH 3.6.x branch.
+
+ v2: backport to nx-libs 3.5.0.x (Mihai Moldovan)
+---
+ nxcomp/Loop.cpp | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+--- a/nxcomp/Loop.cpp
++++ b/nxcomp/Loop.cpp
+@@ -13017,7 +13017,7 @@ int SetLinkAdsl()
+ 
+   control -> LinkMode = LINK_TYPE_ADSL;
+ 
+-  control -> TokenSize  = 512;
++  control -> TokenSize  = 1536;
+   control -> TokenLimit = 24;
+ 
+   control -> SplitMode             = 1;
+@@ -13047,7 +13047,7 @@ int SetLinkWan()
+ 
+   control -> LinkMode = LINK_TYPE_WAN;
+ 
+-  control -> TokenSize  = 768;
++  control -> TokenSize  = 1536;
+   control -> TokenLimit = 24;
+ 
+   control -> SplitMode             = 1;
diff --git a/debian/patches/series b/debian/patches/series
index 6a24429a4..988e11643 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -148,6 +148,7 @@
 1259_nx-X11_Make-RANDR-_set_-timestamps-follow-clien.full.patch
 1260_nx-X11_xserver-Avoid-sending-uninitialized-padd.full.patch
 1270_nx-X11_CVE-2017-2624-Use-timingsafe_memcmp-to-c.full.patch
+1300_nxcomp_Set-TokenSize-to-1536-for-lin.full+lite.patch
 9900-dxpc-license-history.full+lite.patch
 0016_nx-X11_install-location.debian.patch
 0102_xserver-xext_set-securitypolicy-path.debian.patch