Merge pull request #26 from dwilhelm/master

Scale OxyPlot elements based on DPI

External/OxyPlot/OxyPlot/PlotModel/PlotModel.cs

@@ -310,6 +310,28 @@ namespace OxyPlot
             this.Subtitle = subtitle;
         }
 
+        public PlotModel(double dpiXscale, double dpiYscale)
+            : this()
+        {
+            this.PlotMargins = new OxyThickness(this.PlotMargins.Left * dpiXscale,
+                                                this.PlotMargins.Top * dpiYscale,
+                                                this.PlotMargins.Right * dpiXscale,
+                                                this.PlotMargins.Bottom * dpiYscale
+                                               );
+            this.Padding = new OxyThickness(this.Padding.Left * dpiXscale,
+                                            this.Padding.Top * dpiYscale,
+                                            this.Padding.Right * dpiXscale,
+                                            this.Padding.Bottom * dpiYscale
+                                           );
+            this.TitlePadding *= dpiXscale;
+            this.LegendSymbolLength *= dpiXscale;
+            this.LegendSymbolMargin *= dpiXscale;
+            this.LegendPadding *= dpiXscale;
+            this.LegendColumnSpacing *= dpiXscale;
+            this.LegendItemSpacing *= dpiXscale;
+            this.LegendMargin *= dpiXscale;
+        }
+
         /// <summary>
         /// The synchronization root object.
         /// </summary>

GUI/PlotPanel.cs

@@ -35,11 +35,16 @@ namespace OpenHardwareMonitor.GUI {
     private UserOption stackedAxes;
 
     private DateTime now;
+    private float dpiX;
+    private float dpiY;
+    private double dpiXscale = 1;
+    private double dpiYscale = 1;
 
     public PlotPanel(PersistentSettings settings, UnitManager unitManager) {
       this.settings = settings;
       this.unitManager = unitManager;
 
+      this.SetDPI();
       this.model = CreatePlotModel();
 
       this.plot = new Plot();
@@ -168,7 +173,7 @@ namespace OpenHardwareMonitor.GUI {
         axes.Add(type, axis);
       }
 
-      var model = new PlotModel();
+      var model = new PlotModel(this.dpiXscale, this.dpiYscale);
       model.Axes.Add(timeAxis);
       foreach (var axis in axes.Values)
         model.Axes.Add(axis);
@@ -178,6 +183,30 @@ namespace OpenHardwareMonitor.GUI {
       return model;
     }
 
+    private void SetDPI() {
+        // https://msdn.microsoft.com/en-us/library/windows/desktop/dn469266(v=vs.85).aspx
+        const int _default_dpi = 96;
+        Graphics g = this.CreateGraphics();
+
+        try
+        {
+            this.dpiX = g.DpiX;
+            this.dpiY = g.DpiY;
+        }
+        finally
+        {
+            g.Dispose();
+        }
+        if (dpiX > 0)
+        {
+            this.dpiXscale = dpiX / _default_dpi;
+        }
+        if (dpiY > 0)
+        {
+            this.dpiYscale = dpiY / _default_dpi;
+        }
+    }
+
     public void SetSensors(List<ISensor> sensors,
       IDictionary<ISensor, Color> colors) {
       this.model.Series.Clear();