From e120f098db8ab3b79f76d33640ac413053a61d71 Mon Sep 17 00:00:00 2001
From: Andreas Bilke <andreas@bilke.org>
Date: Mon, 20 Nov 2017 11:20:16 +0100
Subject: [PATCH] Disble wayland scaling workaround by default

Add command line option to enable workaround behavor for affected
wayland sessions.
---
 man/pdfpc.in                       | 3 +++
 src/classes/options.vala           | 5 +++++
 src/classes/window/fullscreen.vala | 2 +-
 src/pdfpc.vala                     | 5 +++++
 4 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/man/pdfpc.in b/man/pdfpc.in
index 0f06bc4e..48fa418a 100644
--- a/man/pdfpc.in
+++ b/man/pdfpc.in
@@ -76,6 +76,9 @@ Force to use only one screen
 .BI "\-t, \-\-start\-time"=T
 Start time of the presentation to be used as a countdown. (Format: HH:MM (24h))
 .TP
+.BI "\-W, \-\-wayland-workaround"
+Enable Wayland-specific workaround. This might fix HiDPI scaling problems.
+.TP
 .BI "\-w, \-\-windowed"
 Run in windowed mode
 .TP
diff --git a/src/classes/options.vala b/src/classes/options.vala
index 0ffa3018..fd6f79b2 100644
--- a/src/classes/options.vala
+++ b/src/classes/options.vala
@@ -52,6 +52,11 @@ namespace pdfpc {
          */
         public static bool windowed = false;
 
+        /**
+         * Commandline option to enable Wayland specific scaling workarounds
+         */
+        public static bool wayland_workaround = false;
+
         /**
          * Commandline option which allows the complete disabling of slide caching
          */
diff --git a/src/classes/window/fullscreen.vala b/src/classes/window/fullscreen.vala
index 86fb685b..ba730af5 100644
--- a/src/classes/window/fullscreen.vala
+++ b/src/classes/window/fullscreen.vala
@@ -108,7 +108,7 @@ namespace pdfpc.Window {
             }
 
             this.gdk_scale = this.screen_to_use.get_monitor_scale_factor(this.screen_num_to_use);
-            if (Pdfpc.is_Wayland_backend()) {
+            if (Pdfpc.is_Wayland_backend() && Options.wayland_workaround) {
                 // See issue 214. Wayland is doing some double scaling therefore
                 // we are lying about the actual screen size
                 this.screen_geometry.width /= this.gdk_scale;
diff --git a/src/pdfpc.vala b/src/pdfpc.vala
index 774f7e85..23bcb6eb 100644
--- a/src/pdfpc.vala
+++ b/src/pdfpc.vala
@@ -68,6 +68,7 @@ namespace pdfpc {
             { "start-time", 't', 0, OptionArg.STRING, ref Options.start_time, "Start time of the presentation to be used as a countdown. (Format: HH:MM (24h))", "T" },
             { "version", 'v', 0, 0, ref Options.version, "Print the version string and copyright statement", null },
             { "windowed", 'w', 0, 0, ref Options.windowed, "Run in windowed mode (devel tool)", null},
+            { "wayland-workaround", 'W', 0, 0, ref Options.wayland_workaround, "Enable Wayland-specific workaround. This might fix HiDPI scaling problems", null},
             { "disable-compression", 'z', 0, 0, ref Options.disable_cache_compression, "Disable the compression of slide images to trade memory consumption for speed. (Avg. factor 30)", null },
             { "size", 'Z', 0, OptionArg.STRING, ref Options.size, "Size of the presentation window in width:height format (forces windowed mode)", null},
             { null }
@@ -193,6 +194,10 @@ namespace pdfpc {
                 GLib.printerr("--notes option detected. Disable auto grouping.\n");
             }
 
+            if (Pdfpc.is_Wayland_backend() && !Options.wayland_workaround) {
+                GLib.printerr("If you have wrong scaling of the windows, consider using --wayland-workaround\n");
+            }
+
             ConfigFileReader configFileReader = new ConfigFileReader();
             configFileReader.readConfig(Path.build_filename(Paths.SOURCE_PATH, "rc/pdfpcrc"));
             configFileReader.readConfig(Path.build_filename(Paths.CONF_PATH, "pdfpcrc"));