Separate version

Net40/HandyControl_Net40/Expression/Drawing/MathHelper.cs

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+using System;
+
+namespace HandyControl.Expression.Drawing
+{
+    internal static class MathHelper
+    {
+        public static bool AreClose(double value1, double value2) =>
+            // ReSharper disable once CompareOfFloatsByEqualityOperator
+            value1 == value2 || IsVerySmall(value1 - value2);
+
+        public static double Lerp(double x, double y, double alpha) => x * (1.0 - alpha) + y * alpha;
+
+        public static bool IsVerySmall(double value) => Math.Abs(value) < 1E-06;
+
+        public static bool IsFiniteDouble(double x) => !double.IsInfinity(x) && !double.IsNaN(x);
+
+        public static double DoubleFromMantissaAndExponent(double x, int exp) => x * Math.Pow(2.0, exp);
+
+        public static bool GreaterThan(double value1, double value2) => value1 > value2 && !AreClose(value1, value2);
+
+        public static bool GreaterThanOrClose(double value1, double value2)
+        {
+            if (value1 <= value2)
+            {
+                return AreClose(value1, value2);
+            }
+            return true;
+        }
+
+        public static double Hypotenuse(double x, double y) => Math.Sqrt(x * x + y * y);
+
+        public static bool LessThan(double value1, double value2) => value1 < value2 && !AreClose(value1, value2);
+
+        public static bool LessThanOrClose(double value1, double value2)
+        {
+            if (value1 >= value2)
+            {
+                return AreClose(value1, value2);
+            }
+            return true;
+        }
+
+        public static double EnsureRange(double value, double? min, double? max)
+        {
+            if (min.HasValue && value < min.Value)
+            {
+                return min.Value;
+            }
+            if (max.HasValue && value > max.Value)
+            {
+                return max.Value;
+            }
+            return value;
+        }
+
+        public static double SafeDivide(double lhs, double rhs, double fallback)
+        {
+            if (!IsVerySmall(rhs))
+            {
+                return lhs / rhs;
+            }
+            return fallback;
+        }
+    }
+}