From 6c06aadd37b890d62d349efee4eb728b77f34d03 Mon Sep 17 00:00:00 2001
From: Eryn Wells <eryn@erynwells.me>
Date: Thu, 24 Aug 2017 18:35:16 -0700
Subject: [PATCH] [kit] Add target and feather properties to the Parameters
 struct

---
 MetaballsKit/Metaballs.swift | 10 ++++++----
 MetaballsKit/Shaders.metal   |  7 +++----
 2 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/MetaballsKit/Metaballs.swift b/MetaballsKit/Metaballs.swift
index b748598..4cdb5eb 100644
--- a/MetaballsKit/Metaballs.swift
+++ b/MetaballsKit/Metaballs.swift
@@ -36,12 +36,14 @@ public struct Parameters {
     var size = Size(width: 0, height: 0)
     var numberOfBalls: UInt16 = 0
 
-    let unused1: UInt16 = 0xAB
-    let unused2: UInt32 = 0xCDEF
-    let unused3: UInt16 = 0xBA
+    private var _colorStyle = ColorStyle.singleColor.rawValue
+
+    /// The target sample value. Above this value results in a colored pixel; below is a dark pixel.
+    var target: Float = 1.0
+    /// The amount to feather the alpha of each ball. A value between 0.0 and 1.0.
+    var feather: Float = 0.0
 
     // Color parameters
-    private var _colorStyle = ColorStyle.singleColor.rawValue
     public var color0 = Float4(r: 0, g: 1, b: 0, a: 1)
     public var color1 = Float4()
     public var color2 = Float4()
diff --git a/MetaballsKit/Shaders.metal b/MetaballsKit/Shaders.metal
index 0328390..3294bda 100644
--- a/MetaballsKit/Shaders.metal
+++ b/MetaballsKit/Shaders.metal
@@ -41,11 +41,10 @@ typedef struct {
     short2 size;
     ushort numberOfBalls;
 
-    ushort unused1;
-    uint unused2;
-    ushort unused3;
-
     ushort colorStyle;
+    float target;
+    float feather;
+
     float4 colors[4];
 } Parameters;