From 9ffb9f22faf7c540083e6df828500d54aabcbb56 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Tue, 20 Oct 2015 19:31:41 +0300
Subject: [PATCH] Use float rather than unsigned for refresh rate

Display::set_mode now accepts a rate which is within +-0.5 Hz of
requested and chooses the closest match if there are more than one.
---
 source/graphics/display.cpp     | 23 +++++++++++++++++++----
 source/graphics/display.h       |  2 +-
 source/graphics/videomode.h     |  2 +-
 source/graphics/x11/display.cpp |  2 +-
 4 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/source/graphics/display.cpp b/source/graphics/display.cpp
index de5a069..40112a3 100644
--- a/source/graphics/display.cpp
+++ b/source/graphics/display.cpp
@@ -1,3 +1,4 @@
+#include <cmath>
 #include "display.h"
 #include "display_private.h"
 #include "window.h"
@@ -31,19 +32,33 @@ void Display::restore_mode()
 			set_mode(*i->desktop_mode, false);
 }
 
-const VideoMode *Display::find_mode(const VideoMode &mode) const
+const VideoMode *Display::find_mode(const VideoMode &mode, float rate_tolerance) const
 {
+	const VideoMode *closest = 0;
+	float rate_diff = mode.rate;
 	for(list<VideoMode>::const_iterator i=modes.begin(); i!=modes.end(); ++i)
 	{
 		if(mode.monitor && i->monitor!=mode.monitor)
 			continue;
-		if(mode.rate && i->rate!=mode.rate)
+		if(mode.rate && (i->rate<mode.rate-rate_tolerance || i->rate>mode.rate+rate_tolerance))
 			continue;
-		if(i->width==mode.width && i->height==mode.height)
+		if(i->width!=mode.width || i->height!=mode.height)
+			continue;
+
+		if(mode.rate)
+		{
+			float d = abs(i->rate-mode.rate);
+			if(d<rate_diff)
+			{
+				closest = &*i;
+				rate_diff = d;
+			}
+		}
+		else
 			return &*i;
 	}
 
-	return 0;
+	return closest;
 }
 
 const VideoMode *Display::find_mode(unsigned width, unsigned height) const
diff --git a/source/graphics/display.h b/source/graphics/display.h
index 03912de..9c62b51 100644
--- a/source/graphics/display.h
+++ b/source/graphics/display.h
@@ -39,7 +39,7 @@ public:
 	const VideoMode &get_desktop_mode() const;
 	void set_mode(const VideoMode &, bool = false);
 	void restore_mode();
-	const VideoMode *find_mode(const VideoMode &) const;
+	const VideoMode *find_mode(const VideoMode &, float = 0.5f) const;
 	const VideoMode *find_mode(unsigned, unsigned) const;
 
 	void tick();
diff --git a/source/graphics/videomode.h b/source/graphics/videomode.h
index 2836e11..a9c58bd 100644
--- a/source/graphics/videomode.h
+++ b/source/graphics/videomode.h
@@ -32,7 +32,7 @@ struct VideoMode
 	const Monitor *monitor;
 	unsigned width;
 	unsigned height;
-	unsigned rate;
+	float rate;
 	VideoRotation rotation;
 
 	VideoMode();
diff --git a/source/graphics/x11/display.cpp b/source/graphics/x11/display.cpp
index 15c69a9..50c6d57 100644
--- a/source/graphics/x11/display.cpp
+++ b/source/graphics/x11/display.cpp
@@ -147,7 +147,7 @@ Display::Display(const string &disp_name):
 					VideoMode mode(info->width, info->height);
 					mode.index = modes.size();
 					mode.monitor = &monitor;
-					mode.rate = info->dotClock/(info->hTotal*info->vTotal);
+					mode.rate = static_cast<float>(info->dotClock)/(info->hTotal*info->vTotal);
 					if(find_mode(mode))
 						continue;
 
-- 
2.43.0