Merge pull request #1 from InfinityGhost/smoothingfilter

Add hawku/TabletDriver TabletFilterSmoothing

Author: InfinityGhost

TabletDriverFilters/TabletFilterSmoothing.cs

@@ -0,0 +1,62 @@
+using System;
+using TabletDriverPlugin;
+using TabletDriverPlugin.Attributes;
+using TabletDriverPlugin.Tablet;
+
+namespace TabletDriverFilters
+{
+    using static Math;
+
+    [PluginName("TabletDriver Smoothing Filter")]
+    public class TabletFilterSmoothing : IFilter
+    {
+        private DateTime? _lastFilterTime;
+        private Point _lastPos;
+        private float _timerInterval;
+        private const float _threshold = 0.63f;
+
+        public Point Filter(Point point)
+        {
+            var timeDelta = DateTime.Now - _lastFilterTime;
+            // If a time difference hasn't been established or it has been 100 milliseconds since the last filter
+            if (timeDelta == null || timeDelta.Value.TotalMilliseconds > 100 || _lastPos == null)
+            {
+                SetPreviousState(point);
+                return point;
+            }
+            else
+            {
+                Point pos = new Point(_lastPos.X, _lastPos.Y);
+                float deltaX = point.X - _lastPos.X;
+                float deltaY = point.Y - _lastPos.Y;
+
+                double stepCount = Latency / TimerInterval;
+                double target = 1 - _threshold;
+                double weight = 1.0 - (1.0 / Pow(1.0 / target, 1.0 / stepCount));
+
+                pos.X += (float)(deltaX * weight);
+                pos.Y += (float)(deltaY * weight);
+                SetPreviousState(pos);
+                return pos;
+            }
+        }
+
+        private void SetPreviousState(Point lastPosition)
+        {
+            _lastPos = lastPosition;
+            _lastFilterTime = DateTime.Now;
+        }
+
+        public FilterStage FilterStage => FilterStage.PostTranspose;
+
+        [SliderProperty("Latency", 0f, 5f, 2f)]
+        public float Latency { set; get; }
+
+        [UnitProperty("Timer Interval", "hz")]
+        public float TimerInterval
+        {
+            set => _timerInterval = 1000f / value;
+            get => _timerInterval;
+        }
+    }
+}