automatic tooltips strategy

docs/1.overview/1.10.tooltips.md

@@ -0,0 +1,14 @@
+<div class="text-right edit-article">
+    <a class="btn btn-light" href="https://github.com/beto-rodriguez/LiveCharts2/blob/master/docs/1.overview/1.8.series.md">
+        <div class="d-flex flex-row align-items-center">
+            <div class="me-3">
+                <svg xmlns="http://www.w3.org/2000/svg" enable-background="new 0 0 24 24" height="35px" viewBox="0 0 24 24" width="35px" fill="#404040">
+                <rect fill="none" height="24" width="24" /><path d="M3,10h11v2H3V10z M3,8h11V6H3V8z M3,16h7v-2H3V16z M18.01,12.87l0.71-0.71c0.39-0.39,1.02-0.39,1.41,0l0.71,0.71 c0.39,0.39,0.39,1.02,0,1.41l-0.71,0.71L18.01,12.87z M17.3,13.58l-5.3,5.3V21h2.12l5.3-5.3L17.3,13.58z" /></svg>
+            </div>
+            <span>Edit this article</span>
+        </div>
+    </a>
+</div>
+
+# Tooltips
+

src/LiveChartsCore/CartesianChart.cs

@@ -146,7 +146,24 @@ public override void Update(ChartUpdateParams? chartUpdateParams = null)
         /// <returns></returns>
         public override IEnumerable<TooltipPoint> FindPointsNearTo(PointF pointerPosition)
         {
-            return _chartView.Series.SelectMany(series => series.FindPointsNearTo(this, pointerPosition));
+            var actualStrategy = TooltipFindingStrategy;
+            if (TooltipFindingStrategy == TooltipFindingStrategy.Automatic)
+            {
+                var areAllX = true;
+                var areAllY = true;
+
+                foreach (var series in Series)
+                {
+                    areAllX = areAllX && (series.SeriesProperties & SeriesProperties.PrefersXStrategyTooltips) != 0;
+                    areAllY = areAllY && (series.SeriesProperties & SeriesProperties.PrefersYStrategyTooltips) != 0;
+                }
+
+                actualStrategy = areAllX
+                    ? TooltipFindingStrategy.CompareOnlyX
+                    : (areAllY ? TooltipFindingStrategy.CompareOnlyY : TooltipFindingStrategy.CompareAll);
+            }
+
+            return _chartView.Series.SelectMany(series => series.FindPointsNearTo(this, pointerPosition, actualStrategy));
         }
 
         /// <summary>

src/LiveChartsCore/ColumnSeries.cs

@@ -45,7 +45,9 @@ public abstract class ColumnSeries<TModel, TVisual, TLabel, TDrawingContext> : B
         /// Initializes a new instance of the <see cref="ColumnSeries{TModel, TVisual, TLabel, TDrawingContext}"/> class.
         /// </summary>
         public ColumnSeries()
-            : base(SeriesProperties.Bar | SeriesProperties.PrimaryAxisVerticalOrientation | SeriesProperties.Solid)
+            : base(
+                  SeriesProperties.Bar | SeriesProperties.PrimaryAxisVerticalOrientation |
+                  SeriesProperties.Solid | SeriesProperties.PrefersXStrategyTooltips)
         {
             DataPadding = new PointF(0, 1);
         }

src/LiveChartsCore/Drawing/MotionCanvas.cs

@@ -94,6 +94,8 @@ public void DrawFrame(TDrawingContext context)
 
                     foreach (var geometry in task.GetGeometries(this))
                     {
+                        if (geometry == null) continue;
+
                         geometry.IsValid = true;
                         geometry.CurrentTime = frameTime;
                         if (!task.IsPaused) geometry.Draw(context);

src/LiveChartsCore/ISeries.cs

@@ -156,8 +156,9 @@ public interface ISeries : IDisposable
         /// </summary>
         /// <param name="chart">the chart</param>
         /// <param name="pointerPosition">the pointer position</param>
+        /// <param name="automaticStategy">the already resolved strategy when strategy is set to automatic.</param>
         /// <returns></returns>
-        IEnumerable<TooltipPoint> FindPointsNearTo(IChart chart, PointF pointerPosition);
+        IEnumerable<TooltipPoint> FindPointsNearTo(IChart chart, PointF pointerPosition, TooltipFindingStrategy automaticStategy);
 
         /// <summary>
         /// Marks a given point as a given state.

src/LiveChartsCore/Kernel/ICartesianChartView.cs

@@ -75,6 +75,15 @@ public interface ICartesianChartView<TDrawingContext> : IChartView<TDrawingConte
         /// </value>
         ZoomAndPanMode ZoomMode { get; set; }
 
+
+        /// <summary>
+        /// Gets or sets the tool tip finding strategy.
+        /// </summary>
+        /// <value>
+        /// The tool tip finding strategy.
+        /// </value>
+        TooltipFindingStrategy TooltipFindingStrategy { get; set; }
+
         /// <summary>
         /// Gets or sets the zooming speed from 0 to 1, where 0 is the fastest and 1 the slowest.
         /// </summary>

src/LiveChartsCore/Kernel/IChartView.cs

@@ -113,14 +113,6 @@ public interface IChartView
         /// The tooltip position.
         /// </value>
         TooltipPosition TooltipPosition { get; set; }
-
-        /// <summary>
-        /// Gets or sets the tooltip finding strategy.
-        /// </summary>
-        /// <value>
-        /// The tooltip finding strategy.
-        /// </value>
-        TooltipFindingStrategy TooltipFindingStrategy { get; set; }
     }
 
     /// <summary>

src/LiveChartsCore/Kernel/LiveChartsSettings.cs

@@ -100,7 +100,7 @@ public class LiveChartsSettings
         /// <value>
         /// The default tooltip finding strategy.
         /// </value>
-        public TooltipFindingStrategy DefaultTooltipFindingStrategy { get; set; } = TooltipFindingStrategy.CompareOnlyX;
+        public TooltipFindingStrategy DefaultTooltipFindingStrategy { get; set; } = TooltipFindingStrategy.Automatic;
 
         /// <summary>
         /// Gets the theme identifier.

src/LiveChartsCore/Kernel/RectangleHoverArea.cs

@@ -22,6 +22,7 @@
 
 using LiveChartsCore.Measure;
 using System;
+using System.Diagnostics;
 using System.Drawing;
 
 namespace LiveChartsCore.Kernel
@@ -88,12 +89,14 @@ public override float GetDistanceToPoint(PointF point, TooltipFindingStrategy st
             var dx = point.X - (X + Width * 0.5f);
             var dy = point.Y - (Y + Height * 0.5f);
 
+            //Trace.WriteLine($"{Y:N2} {point.Y:N2}");
+
             return strategy switch
             {
-                TooltipFindingStrategy.CompareAll => (float)Math.Sqrt(Math.Pow(dx, 2) + Math.Pow(dx, 2)),
+                TooltipFindingStrategy.CompareAll => (float)Math.Sqrt(Math.Pow(dx, 2) + Math.Pow(dy, 2)),
                 TooltipFindingStrategy.CompareOnlyX => Math.Abs(dx),
                 TooltipFindingStrategy.CompareOnlyY => Math.Abs(dy),
-                _ => throw new Exception($"The strategy {strategy} is not supported."),
+                TooltipFindingStrategy.Automatic or _ => throw new Exception($"The strategy {strategy} is not supported.")
             };
         }
 

src/LiveChartsCore/Kernel/SeriesProperties.cs

@@ -90,6 +90,21 @@ public enum SeriesProperties
         /// <summary>
         /// The solid
         /// </summary>
-        Solid = 1 << 13
+        Solid = 1 << 13,
+
+        /// <summary>
+        /// The prefers x tool tips
+        /// </summary>
+        PrefersXStrategyTooltips = 1 << 14,
+
+        /// <summary>
+        /// The prefers y tool tips
+        /// </summary>
+        PrefersYStrategyTooltips = 1 << 15,
+
+        /// <summary>
+        /// The prefers xy tool tips
+        /// </summary>
+        PrefersXYStrategyTooltips = 1 << 16
     }
 }

src/LiveChartsCore/LineSeries.cs

@@ -56,7 +56,9 @@ public class LineSeries<TModel, TVisual, TLabel, TDrawingContext, TPathGeometry,
         /// </summary>
         /// <param name="isStacked">if set to <c>true</c> [is stacked].</param>
         public LineSeries(bool isStacked = false)
-            : base(SeriesProperties.Line | SeriesProperties.PrimaryAxisVerticalOrientation | (isStacked ? SeriesProperties.Stacked : 0) | SeriesProperties.Sketch)
+            : base(
+                  SeriesProperties.Line | SeriesProperties.PrimaryAxisVerticalOrientation |
+                  (isStacked ? SeriesProperties.Stacked : 0) | SeriesProperties.Sketch | SeriesProperties.PrefersXStrategyTooltips)
         {
             DataPadding = new PointF(0.5f, 1f);
             HoverState = LiveCharts.LineSeriesHoverKey;

src/LiveChartsCore/Measure/TooltipFindingStrategy.cs

@@ -23,10 +23,15 @@
 namespace LiveChartsCore.Measure
 {
     /// <summary>
-    /// Defines the tooltip finding strategy.
+    /// Defines the tool tip finding strategy.
     /// </summary>
     public enum TooltipFindingStrategy
     {
+        /// <summary>
+        /// The automatic mode, it will be calculated based on the series in the chart.
+        /// </summary>
+        Automatic,
+
         /// <summary>
         /// Compares X and Y coordinates.
         /// </summary>

src/LiveChartsCore/PieChart.cs

@@ -127,7 +127,8 @@ public PieChart(
         /// <returns></returns>
         public override IEnumerable<TooltipPoint> FindPointsNearTo(PointF pointerPosition)
         {
-            return _chartView.Series.SelectMany(series => series.FindPointsNearTo(this, pointerPosition));
+            return _chartView.Series.SelectMany(
+                series => series.FindPointsNearTo(this, pointerPosition, TooltipFindingStrategy.CompareAll));
         }
 
         /// <inheritdoc cref="IChart.Update(ChartUpdateParams?)" />
@@ -175,7 +176,6 @@ protected override void Measure()
                 legend = _chartView.Legend;
 
                 tooltipPosition = _chartView.TooltipPosition;
-                tooltipFindingStrategy = _chartView.TooltipFindingStrategy;
                 tooltip = _chartView.Tooltip;
 
                 animationsSpeed = _chartView.AnimationsSpeed;

src/LiveChartsCore/RowSeries.cs

@@ -46,7 +46,9 @@ public class RowSeries<TModel, TVisual, TLabel, TDrawingContext> : BarSeries<TMo
         /// Initializes a new instance of the <see cref="RowSeries{TModel, TVisual, TLabel, TDrawingContext}"/> class.
         /// </summary>
         public RowSeries()
-            : base(SeriesProperties.Bar | SeriesProperties.PrimaryAxisHorizontalOrientation | SeriesProperties.Solid) { }
+            : base(
+                  SeriesProperties.Bar | SeriesProperties.PrimaryAxisHorizontalOrientation
+                  | SeriesProperties.Solid | SeriesProperties.PrefersYStrategyTooltips) { }
 
         /// <inheritdoc cref="CartesianSeries{TModel, TVisual, TLabel, TDrawingContext}.Measure"/>
         public override void Measure(
@@ -59,7 +61,7 @@ public override void Measure(
                 primaryAxis.PreviousDataBounds == null ? null : new Scaler(drawLocation, drawMarginSize, primaryAxis);
             var primaryScale = new Scaler(drawLocation, drawMarginSize, secondaryAxis);
 
-            var uw = secondaryScale.ToPixels((float)primaryAxis.UnitWidth) - secondaryScale.ToPixels(0f);
+            var uw = secondaryScale.ToPixels(0f) - secondaryScale.ToPixels((float)primaryAxis.UnitWidth);
             var uwm = 0.5f * uw;
 
             uw -= (float)GroupPadding;
@@ -81,7 +83,7 @@ public override void Measure(
 
             if (uw > MaxBarWidth)
             {
-                uw = (float)MaxBarWidth * -1;
+                uw = (float)MaxBarWidth;
                 uwm = uw / 2f;
             }
 
@@ -171,7 +173,7 @@ public override void Measure(
                 sizedGeometry.Ry = ry;
                 sizedGeometry.RemoveOnCompleted = false;
 
-                point.Context.HoverArea = new RectangleHoverArea().SetDimensions(primary, secondary - uwm + cp, b, uw);
+                point.Context.HoverArea = new RectangleHoverArea().SetDimensions(cx, y, b, uw);
 
                 OnPointMeasured(point);
                 _ = toDeletePoints.Remove(point);

src/LiveChartsCore/ScatterSeries.cs

@@ -49,7 +49,7 @@ public class ScatterSeries<TModel, TVisual, TLabel, TDrawingContext> : Cartesian
         /// Initializes a new instance of the <see cref="ScatterSeries{TModel, TVisual, TLabel, TDrawingContext}"/> class.
         /// </summary>
         public ScatterSeries()
-            : base(SeriesProperties.Scatter | SeriesProperties.Solid)
+            : base(SeriesProperties.Scatter | SeriesProperties.Solid | SeriesProperties.PrefersXYStrategyTooltips)
         {
             DataPadding = new PointF(1, 1);
 

src/LiveChartsCore/Series.cs

@@ -30,6 +30,7 @@
 using System.ComponentModel;
 using System.Runtime.CompilerServices;
 using System.Linq;
+using System.Diagnostics;
 
 namespace LiveChartsCore
 {
@@ -223,9 +224,9 @@ IEnumerable<ChartPoint> ISeries.Fetch(IChart chart)
             return Fetch(chart);
         }
 
-        IEnumerable<TooltipPoint> ISeries.FindPointsNearTo(IChart chart, PointF pointerPosition)
+        IEnumerable<TooltipPoint> ISeries.FindPointsNearTo(IChart chart, PointF pointerPosition, TooltipFindingStrategy automaticStategy)
         {
-            return FilterTooltipPoints(Fetch(chart), chart, pointerPosition);
+            return FilterTooltipPoints(Fetch(chart), chart, pointerPosition, automaticStategy);
         }
 
         /// <inheritdoc />
@@ -383,7 +384,7 @@ protected void OnPropertyChanged([CallerMemberName] string? propertyName = null)
         }
 
         private IEnumerable<TooltipPoint> FilterTooltipPoints(
-            IEnumerable<ChartPoint>? points, IChart chart, PointF pointerPosition)
+            IEnumerable<ChartPoint>? points, IChart chart, PointF pointerPosition, TooltipFindingStrategy automaticStategy)
         {
             if (points == null) return Enumerable.Empty<TooltipPoint>();
             var tolerance = float.MaxValue;
@@ -406,11 +407,12 @@ private IEnumerable<TooltipPoint> FilterTooltipPoints(
                         tolerance = (float)Math.Sqrt(Math.Pow(uwx, 2) + Math.Pow(uwy, 2));
                         break;
                     case TooltipFindingStrategy.CompareOnlyX:
-                        tolerance = uwx;
+                        tolerance = Math.Abs(uwx);
                         break;
                     case TooltipFindingStrategy.CompareOnlyY:
-                        tolerance = uwy;
+                        tolerance = Math.Abs(uwy);
                         break;
+                    case TooltipFindingStrategy.Automatic:
                     default:
                         break;
                 }
@@ -421,7 +423,7 @@ private IEnumerable<TooltipPoint> FilterTooltipPoints(
             foreach (var point in points)
             {
                 if (point == null || point.Context.HoverArea == null) continue;
-                var d = point.Context.HoverArea.GetDistanceToPoint(pointerPosition, chart.TooltipFindingStrategy);
+                var d = point.Context.HoverArea.GetDistanceToPoint(pointerPosition, automaticStategy); //chart.TooltipFindingStrategy
                 if (d > tolerance || d > minD.Item1) continue;
 
                 if (minD.Item1 == d)
@@ -434,6 +436,8 @@ private IEnumerable<TooltipPoint> FilterTooltipPoints(
                 minD = new Tuple<float, List<TooltipPoint>>(d, new List<TooltipPoint> { new TooltipPoint(this, point) });
             }
 
+            Trace.WriteLine(minD.Item2.Count);
+
             return minD.Item2;
         }
 

src/LiveChartsCore/StackedColumnSeries.cs

@@ -46,7 +46,9 @@ public class StackedColumnSeries<TModel, TVisual, TLabel, TDrawingContext> : Sta
         /// Initializes a new instance of the <see cref="StackedColumnSeries{TModel, TVisual, TLabel, TDrawingContext}"/> class.
         /// </summary>
         public StackedColumnSeries()
-            : base(SeriesProperties.Bar | SeriesProperties.PrimaryAxisVerticalOrientation | SeriesProperties.Stacked | SeriesProperties.Solid)
+            : base(
+                  SeriesProperties.Bar | SeriesProperties.PrimaryAxisVerticalOrientation | SeriesProperties.Stacked |
+                  SeriesProperties.Solid | SeriesProperties.PrefersXStrategyTooltips)
         {
             DataPadding = new PointF(0, 1);
         }

src/LiveChartsCore/StackedRowSeries.cs

@@ -46,7 +46,9 @@ public class StackedRowSeries<TModel, TVisual, TLabel, TDrawingContext> : Stacke
         /// Initializes a new instance of the <see cref="StackedRowSeries{TModel, TVisual, TLabel, TDrawingContext}"/> class.
         /// </summary>
         public StackedRowSeries()
-            : base(SeriesProperties.Bar | SeriesProperties.PrimaryAxisHorizontalOrientation | SeriesProperties.Stacked | SeriesProperties.Solid)
+            : base(
+                  SeriesProperties.Bar | SeriesProperties.PrimaryAxisHorizontalOrientation | SeriesProperties.Stacked |
+                  SeriesProperties.Solid | SeriesProperties.PrefersXStrategyTooltips)
         {
 
         }

src/skiasharp/LiveChartsCore.SkiaSharp.Avalonia/CartesianChart.axaml.cs

@@ -398,7 +398,7 @@ public TooltipPosition TooltipPosition
             set => SetValue(TooltipPositionProperty, value);
         }
 
-        /// <inheritdoc cref="IChartView.TooltipFindingStrategy" />
+        /// <inheritdoc cref="ICartesianChartView{TDrawingContext}.TooltipFindingStrategy" />
         public TooltipFindingStrategy TooltipFindingStrategy
         {
             get => (TooltipFindingStrategy)GetValue(TooltipFindingStrategyProperty);

src/skiasharp/LiveChartsCore.SkiaSharp.Avalonia/PieChart.axaml.cs

@@ -168,13 +168,6 @@ public PieChart()
             AvaloniaProperty.Register<CartesianChart, TooltipPosition>(
                 nameof(TooltipPosition), LiveCharts.CurrentSettings.DefaultTooltipPosition, inherits: true);
 
-        /// <summary>
-        /// The tool tip finding strategy property
-        /// </summary>
-        public static readonly AvaloniaProperty<TooltipFindingStrategy> TooltipFindingStrategyProperty =
-            AvaloniaProperty.Register<CartesianChart, TooltipFindingStrategy>(
-                nameof(LegendPosition), LiveCharts.CurrentSettings.DefaultTooltipFindingStrategy, inherits: true);
-
         /// <summary>
         /// The tool tip font family property
         /// </summary>
@@ -375,13 +368,6 @@ public TooltipPosition TooltipPosition
             set => SetValue(TooltipPositionProperty, value);
         }
 
-        /// <inheritdoc cref="IChartView.TooltipFindingStrategy" />
-        public TooltipFindingStrategy TooltipFindingStrategy
-        {
-            get => (TooltipFindingStrategy)GetValue(TooltipFindingStrategyProperty);
-            set => SetValue(TooltipFindingStrategyProperty, value);
-        }
-
         /// <summary>
         /// Gets or sets the tool data tip template.
         /// </summary>