Merge pull request #1332 from SixLabors/sp/bokeh-blur-init-tweaks

Bokeh blur constructor tweaks (input validation, tiny speedup)

Author: antonfirsov

src/ImageSharp/Processing/Processors/Convolution/BokehBlurProcessor.cs

@@ -29,8 +29,10 @@ public sealed class BokehBlurProcessor : IImageProcessor
         /// Initializes a new instance of the <see cref="BokehBlurProcessor"/> class.
         /// </summary>
         public BokehBlurProcessor()
-            : this(DefaultRadius, DefaultComponents, DefaultGamma)
         {
+            this.Radius = DefaultRadius;
+            this.Components = DefaultComponents;
+            this.Gamma = DefaultGamma;
         }
 
         /// <summary>
@@ -47,6 +49,8 @@ public BokehBlurProcessor()
         /// </param>
         public BokehBlurProcessor(int radius, int components, float gamma)
         {
+            Guard.MustBeGreaterThan(radius, 0, nameof(radius));
+            Guard.MustBeBetweenOrEqualTo(components, 1, 6, nameof(components));
             Guard.MustBeGreaterThanOrEqualTo(gamma, 1, nameof(gamma));
 
             this.Radius = radius;

tests/ImageSharp.Tests/Processing/Processors/Convolution/BokehBlurTest.cs

@@ -35,6 +35,19 @@ [[ 0.00451261+0.0165137j   0.02161237-0.00299122j  0.00387479-0.02682816j
            0.02565295+0.01611732j  0.0153483+0.01605112j   0.00698622+0.01370844j
            0.00135338+0.00998296j -0.00152245+0.00604545j -0.00227282+0.002851j  ]]";
 
+        [Theory]
+        [InlineData(-10, 2, 3f)]
+        [InlineData(-1, 2, 3f)]
+        [InlineData(0, 2, 3f)]
+        [InlineData(20, -1, 3f)]
+        [InlineData(20, -0, 3f)]
+        [InlineData(20, 4, -10f)]
+        [InlineData(20, 4, 0f)]
+        public void VerifyBokehBlurProcessorArguments_Fail(int radius, int components, float gamma)
+        {
+            Assert.Throws<ArgumentOutOfRangeException>(() => new BokehBlurProcessor(radius, components, gamma));
+        }
+
         [Fact]
         public void VerifyComplexComponents()
         {