Fix: Fonts, Legend Markers, and Radar Rotation Direction (ScottPlot#5048)

* Fonts.Reset()

* Legend: improve default marker styling

extends ScottPlot#5006

* Radar: use new polar plot rotation features

Author: swharden

CHANGELOG.md

@@ -27,6 +27,7 @@ _Not yet on NuGet..._
 * Angle: Added `Inverted` property and support for `Angle` comparison using equality operators
 * Polar Axis: Added a `Clockwise` property to support clockwise and counter-clockwise translation between Polar and Cartesian coordinates (#5028, #4884, #5046) @CoderPM2011, @mattwelch2000
 * WinUI: Improved support for plots with transparent backgrounds (#5026, #5029) @diluculo
+* Font: Added `Fonts.Reset()` to restore default styling options (#5013) @aespitia
 
 ## ScottPlot 5.0.55
 _Published on [NuGet](https://www.nuget.org/profiles/ScottPlot) on 2025-03-22_

src/ScottPlot5/ScottPlot5 Cookbook/RecipeBase.cs

@@ -40,6 +40,7 @@ public void Execute(Plot plot)
     public void ResetRandomNumberGenerator()
     {
         Generate.RandomData.Seed(0);
+        Fonts.Reset();
     }
 
     [TearDown]

src/ScottPlot5/ScottPlot5 Cookbook/Recipes/General/Legend.cs

@@ -114,21 +114,21 @@ public override void Execute()
 
     public class LegendOverrideSymbol : RecipeBase
     {
-        public override string Name => "Legend Default Marker";
-        public override string Description => @"You can override the default rectangular marker used when rendering the legend.  It also maintains the desired marker for manually added items.";
+        public override string Name => "Legend Marker Shape Override";
+        public override string Description => "Use the legend shape override " +
+            "to force all legend items to display using the given marker shape.";
 
         [Test]
         public override void Execute()
         {
+            myPlot.Legend.MarkerShapeOverride = MarkerShape.FilledCircle;
+
             var sig1 = myPlot.Add.Signal(Generate.Sin(51));
             sig1.LegendText = "Sin";
 
             var sig2 = myPlot.Add.Signal(Generate.Cos(51));
             sig2.LegendText = "Cos";
 
-            myPlot.Legend.MarkerShapeDefault = MarkerShape.FilledCircle;
-
-
             LegendItem item1 = new()
             {
                 MarkerColor = Colors.Red,

src/ScottPlot5/ScottPlot5 Cookbook/Recipes/PlotTypes/Radar.cs

@@ -99,6 +99,8 @@ public override void Execute()
             };
 
             var radar = myPlot.Add.Radar(values);
+            radar.Series[0].LegendText = "A";
+            radar.Series[1].LegendText = "B";
 
             string[] spokeLabels = { "Wins", "Poles", "Podiums", "Points", "DNFs" };
             radar.PolarAxis.SetSpokes(spokeLabels, length: 110);

src/ScottPlot5/ScottPlot5/Fonts.cs

@@ -31,15 +31,16 @@ public static void AddFontFile(string name, string path, bool bold = false, bool
         FontResolvers.Add(resolver);
     }
 
-    /// <summary>
-    /// This font is used for almost all text rendering.
-    /// </summary>
-    public static string Default { get; set; } = SystemFontResolver.InstalledSansFont();
     public static FontWeight? DefaultWeight { get; set; }
     public static FontSlant? DefaultSlant { get; set; }
     public static FontSpacing? DefaultWidth { get; set; }
     public static SKTypeface? DefaultFontStyle { get; set; }
 
+    /// <summary>
+    /// This font is used for almost all text rendering.
+    /// </summary>
+    public static string Default { get; set; } = SystemFontResolver.InstalledSansFont();
+
     /// <summary>
     /// Name of a sans-serif font present on the system
     /// </summary>
@@ -289,4 +290,17 @@ public static List<int> GetStandaloneCodePoints(IEnumerable<List<int>> codePoint
     }
 
     #endregion
+
+    public static void Reset()
+    {
+        DefaultWeight = null;
+        DefaultSlant = null;
+        DefaultWidth = null;
+        DefaultFontStyle = null;
+
+        Default = SystemFontResolver.InstalledSansFont();
+        Sans = SystemFontResolver.InstalledSansFont();
+        Serif = SystemFontResolver.InstalledSerifFont();
+        Monospace = SystemFontResolver.InstalledMonospaceFont();
+    }
 }

src/ScottPlot5/ScottPlot5/Plottables/Radar.cs

@@ -5,7 +5,11 @@ public class Radar() : IPlottable, IManagesAxisLimits
     /// <summary>
     /// The polar axis drawn beneath each radar series polygon
     /// </summary>
-    public PolarAxis PolarAxis { get; set; } = new() { Rotation = Angle.FromDegrees(90) };
+    public PolarAxis PolarAxis { get; set; } = new()
+    {
+        Rotation = Angle.FromDegrees(-90),
+        Clockwise = true,
+    };
 
     /// <summary>
     /// A collection of RadarSeries, each of which hold a set of values and the styling information that controls how the shape is rendered
@@ -59,7 +63,7 @@ public virtual void Render(RenderPack rp)
 
         for (int i = 0; i < Series.Count; i++)
         {
-            Coordinates[] cs1 = PolarAxis.GetCoordinates(Series[i].Values, clockwise: true);
+            Coordinates[] cs1 = PolarAxis.GetCoordinates(Series[i].Values);
             Pixel[] pixels = cs1.Select(Axes.GetPixel).ToArray();
             Drawing.FillPath(rp.Canvas, paint, pixels, Series[i].FillStyle);
             Drawing.DrawPath(rp.Canvas, paint, pixels, Series[i].LineStyle, close: true);

src/ScottPlot5/ScottPlot5/Plottables/Signal.cs

@@ -54,7 +54,13 @@ public Color Color
 
     public AxisLimits GetAxisLimits() => Data.GetLimits();
 
-    public IEnumerable<LegendItem> LegendItems => LegendItem.Single(this, LegendText, MarkerStyle, LineStyle);
+    public IEnumerable<LegendItem> LegendItems
+    {
+        get
+        {
+            return LegendItem.Single(this, LegendText, MarkerStyle, LineStyle);
+        }
+    }
 
     private CoordinateRange GetVisibleXRange(PixelRect dataRect)
     {

src/ScottPlot5/ScottPlot5/Primitives/Legend.cs

@@ -114,7 +114,10 @@ public class Legend(Plot plot) : IPlottable, IHasOutline, IHasBackground, IHasSh
     public IEnumerable<LegendItem> LegendItems => LegendItem.None;
     public AxisLimits GetAxisLimits() => AxisLimits.NoLimits;
 
-    public MarkerShape MarkerShapeDefault { get; set; } = MarkerShape.None;
+    /// <summary>
+    /// If supplied, always use this marker shape
+    /// </summary>
+    public MarkerShape? MarkerShapeOverride { get; set; } = null;
 
     public bool DisplayPlottableLegendItems { get; set; } = true;
 
@@ -294,10 +297,16 @@ private void RenderLayout(SKCanvas canvas, LegendLayout layout)
             PixelRect symbolFillOutlineRect = symbolFillRect.Expand(1 - item.OutlineWidth);
             PixelLine symbolLine = new(symbolRect.RightCenter, symbolRect.LeftCenter);
 
-            if (item.MarkerShape == MarkerShape.None && item.MarkerStyle.Shape == MarkerShape.None)
+            if (MarkerShapeOverride.HasValue)
             {
-                item.MarkerShape = MarkerShapeDefault != MarkerShape.None ? MarkerShapeDefault : MarkerShape.None;
-                item.MarkerColor = item.MarkerColor == Colors.Transparent ? Colors.Black : item.MarkerColor;
+                item.MarkerShape = MarkerShapeOverride.Value;
+
+                if (item.MarkerColor == Colors.Transparent)
+                    item.MarkerColor = Colors.Black;
+
+                // NOTE: Some plottables like signal plots have dynamically sized markers that can get very small
+                if (item.MarkerSize < 5)
+                    item.MarkerSize = item.LabelFontSize;
             }
 
             item.LabelStyle.Render(canvas, labelRect.LeftCenter, paint, true);
@@ -308,33 +317,9 @@ private void RenderLayout(SKCanvas canvas, LegendLayout layout)
                 Drawing.DrawRectangle(canvas, labelRect, Colors.Magenta.WithAlpha(.2));
             }
 
-            if (MarkerShapeDefault != MarkerShape.None)
-            {
-                item.MarkerStyle.Shape = item.MarkerShape != MarkerShape.None ? item.MarkerShape : MarkerShapeDefault;
-
-                //NOTE: tried this but size seems to be defaulting something to something small, so you can barely see the shape, defaulting to font size for now
-                //item.MarkerStyle.Size = item.MarkerStyle.Size != 0 ? item.MarkerStyle.Size : item.LabelFontSize;
-                item.MarkerStyle.Size = item.LabelFontSize;
-            }
-            else
-            {
-                item.MarkerStyle.Shape = item.MarkerShape;
-
-                // If the marker size is not set, use the label font size as a fallback
-                //NOTE: Same as above, tried it, but somehow the default is really small, setting to font size for now.
-                //item.MarkerStyle.Size = item.MarkerStyle.Shape != MarkerShape.None && item.MarkerStyle.Size != 0? item.MarkerStyle.Size : item.LabelFontSize;
-
-                item.MarkerStyle.Size = item.LabelFontSize;
-
-                if (item.MarkerShape == MarkerShape.None && item.MarkerStyle.Shape == MarkerShape.None)
-                {
-                    item.LineStyle.Render(canvas, symbolLine, paint);
-                }
-
-                item.FillStyle.Render(canvas, symbolFillRect, paint);
-                item.OutlineStyle.Render(canvas, symbolFillOutlineRect, paint);
-            }
-
+            item.LineStyle.Render(canvas, symbolLine, paint);
+            item.FillStyle.Render(canvas, symbolFillRect, paint);
+            item.OutlineStyle.Render(canvas, symbolFillOutlineRect, paint);
             item.MarkerStyle.Render(canvas, symbolRect.Center, paint);
             item.ArrowStyle.Render(canvas, symbolLine, paint);