Merge pull request #1462 from Unity-Technologies/sg/spheremasknode

Added Sphere Mask Node

com.unity.shadergraph/CHANGELOG.md

 
 This adds gradient functionality via two new nodes. The Sample Gradient node samples a gradient given a Time parameter. You can define this gradient on the Gradient slot control view. The Gradient Asset node defines a gradient that can be sampled by multiple Sample Gradient nodes using different Time parameters.
 
+### Sphere Mask Node
+
+![](.data/sphereMask.png)
+
+With this node, you can create a sphere mask. Indicate the starting coordinate and center point. The sphere mask uses these with the **Radius** and **Hardness** parameters. Sphere mask functionality works in both 2D and 3D spaces, and is based on the vector coordinates in the **Coords and Center** input.
+
 ### Texture3D and Texture2D Array
 
 ![](.data/texture_nodes.png)

com.unity.shadergraph/.data/sphereMask.PNG

+version https://git-lfs.github.com/spec/v1
+oid sha256:8df3a610b0b2a3f8d3b6a2b9ddb563c3a74e682055b53bc728ac7f795870d9ad
+size 91474

com.unity.shadergraph/Editor/Data/Nodes/Math/Vector/SphereMaskNode.cs

+using System.Reflection;
+using UnityEngine;
+
+namespace UnityEditor.ShaderGraph
+{
+    [Title("Math", "Vector", "Sphere Mask")]
+    public class SphereMaskNode : CodeFunctionNode
+    {
+        public SphereMaskNode()
+        {
+            name = "Sphere Mask";
+        }
+
+        public override string documentationURL
+        {
+            get { return "https://github.com/Unity-Technologies/ShaderGraph/wiki/Sphere-Mask-Node"; }
+        }
+
+        protected override MethodInfo GetFunctionToConvert()
+        {
+            return GetType().GetMethod("SphereMask", BindingFlags.Static | BindingFlags.NonPublic);
+        }
+
+        static string SphereMask(
+            [Slot(0, Binding.None)] DynamicDimensionVector Coords,
+            [Slot(1, Binding.None, 0.5f, 0.5f, 0.5f, 0.5f)] DynamicDimensionVector Center,
+            [Slot(2, Binding.None, 0.1f, 0.1f, 0.1f, 0.1f)] Vector1 Radius,
+            [Slot(3, Binding.None, 0.8f, 0.8f, 0.8f, 0.8f)] Vector1 Hardness,
+            [Slot(4, Binding.None)] out DynamicDimensionVector Out)
+        {
+            return
+                @"
+{
+	Out = 1 - saturate((distance(Coords, Center) - Radius) / (1 - Hardness));
+}
+";
+        }
+    }
+}

com.unity.shadergraph/Editor/Data/Nodes/Math/Vector/SphereMaskNode.cs.meta

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