Revert "added sphere mask node"

This reverts commit 8e71abaf5cc697787f4dc4c4e2c6d59eeb30d093.

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)
-
-This adds sphere mask functionality via one new node. Given a starting coordinate and center point, you can create a sphere mask using the Radius and Hardness parameters. Will function in 2d or 3d space, based on the vector coordinates given in the Coords and Center input.
 
 ### Show generated code
 

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

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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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