diff --git a/Metaballs-macOS/ViewController.swift b/Metaballs-macOS/ViewController.swift
index 5adaa2d..31c5987 100644
--- a/Metaballs-macOS/ViewController.swift
+++ b/Metaballs-macOS/ViewController.swift
@@ -13,7 +13,7 @@ class ViewController: NSViewController, RendererDelegate {
     private static func defaultParameters() -> Parameters {
         var p = Parameters()
         let defaults = UserDefaults.standard
-        let style = defaults.colorStyle ?? .gradient2Horizontal
+        let style = defaults.colorStyle ?? .gradient2
         p.colorStyle = style
         let color0 = defaults.color0 ?? Float4(0.50, 0.79, 1, 1)
         p.color0 = color0
diff --git a/MetaballsKit/Metaballs.swift b/MetaballsKit/Metaballs.swift
index a679234..128ced6 100644
--- a/MetaballsKit/Metaballs.swift
+++ b/MetaballsKit/Metaballs.swift
@@ -16,14 +16,10 @@ public enum MetaballsError: Error {
 public enum ColorStyle: UInt32 {
     /// Single flat color
     case singleColor = 1
-    /// Two color horizontal gradient
-    case gradient2Horizontal = 2
-    /// Two color vertical gradient
-    case gradient2Vertical = 3
-    /// Four color gradient from corners
-    case gradient4Corners = 4
-    /// Four color gradient from middle of sides
-    case gradient4Sides = 5
+    /// Two color gradient
+    case gradient2 = 2
+    /// Four color gradient
+    case gradient4 = 4
 }
 
 public struct Parameters {
diff --git a/MetaballsKit/PreferencesViewController.swift b/MetaballsKit/PreferencesViewController.swift
index d91a5f6..074f1f0 100644
--- a/MetaballsKit/PreferencesViewController.swift
+++ b/MetaballsKit/PreferencesViewController.swift
@@ -25,15 +25,17 @@ public class PreferencesViewController: NSViewController {
         return [
             StyleItem(name: NSLocalizedString("Single Color", comment: "single color menu item"),
                       tag: Int(ColorStyle.singleColor.rawValue),
-                      colorNames: [NSLocalizedString("Color", comment: "single color name")]),
-            StyleItem(name: NSLocalizedString("Two Color Gradient — Horizontal", comment: "two color horizontal gradient menu item"),
-                      tag: Int(ColorStyle.gradient2Horizontal.rawValue),
-                      colorNames: [NSLocalizedString("Right", comment: "two color horizontal gradient, color 1"),
-                                   NSLocalizedString("Left", comment: "two color horizontal gradient, color 2")]),
-            StyleItem(name: NSLocalizedString("Two Color Gradient — Vertical", comment: "two color vertical gradient menu item"),
-                      tag: Int(ColorStyle.gradient2Vertical.rawValue),
-                      colorNames: [NSLocalizedString("Top", comment: "two color vertical gradient, color 1"),
-                                   NSLocalizedString("Bottom", comment: "two color vertical gradient, color 2")]),
+                      colorNames: [NSLocalizedString("A", comment: "first color")]),
+            StyleItem(name: NSLocalizedString("Two Color Gradient", comment: "two color gradient menu item"),
+                      tag: Int(ColorStyle.gradient2.rawValue),
+                      colorNames: [NSLocalizedString("A", comment: "first color"),
+                                   NSLocalizedString("B", comment: "second color")]),
+            StyleItem(name: NSLocalizedString("Four Color Gradient", comment: "four color gradient menu item"),
+                      tag: Int(ColorStyle.gradient4.rawValue),
+                      colorNames: [NSLocalizedString("A", comment: "first color"),
+                                   NSLocalizedString("B", comment: "second color"),
+                                   NSLocalizedString("C", comment: "third color"),
+                                   NSLocalizedString("D", comment: "fourth color")]),
         ]
     }
 
diff --git a/MetaballsKit/Shaders.metal b/MetaballsKit/Shaders.metal
index b1ab61e..21b344f 100644
--- a/MetaballsKit/Shaders.metal
+++ b/MetaballsKit/Shaders.metal
@@ -27,14 +27,10 @@ typedef struct {
 typedef enum {
     /// Single flat color
     SingleColor = 1,
-    /// Two color horizontal gradient
-    Gradient2Horizontal = 2,
-    /// Two color vertical gradient
-    Gradient2Vertical = 3,
-    /// Four color gradient from corners
-    Gradient4Corners = 4,
-    /// Four color gradient from middle of sides
-    Gradient4Sides = 5,
+    /// Two color gradient
+    Gradient2 = 2,
+    /// Four color gradient
+    Gradient4 = 4,
 } ColorStyle;
 
 typedef struct {
@@ -88,19 +84,26 @@ sampleToColorShader(RasterizerData in               [[stage_in]],
         case SingleColor:
             out = singleColor(sample, target, feather, parameters.colors[0]);
             break;
-        case Gradient2Horizontal: {
-            const float3 transformedColor = (parameters.colorTransform * float3(in.position.xy, 1.0));
+        case Gradient2: {
+            const float3 transformedColor = parameters.colorTransform * float3(in.position.xy, 1.0);
             const float blend = transformedColor.x / parameters.size[0];
-            out = gradient2(sample, target, feather, blend, parameters.colors[0], parameters.colors[1]);
+            const float4 color = mix(parameters.colors[0], parameters.colors[1], blend);
+            out = singleColor(sample, target, feather, color);
             break;
         }
-        case Gradient2Vertical: {
-            const float blend = in.position.y / parameters.size[1];
-            out = gradient2(sample, target, feather, blend, parameters.colors[0], parameters.colors[1]);
+        case Gradient4: {
+            const float3 transformedColorCoords = parameters.colorTransform * float3(in.position.xy, 1.0);
+            const float2 blend = float2(transformedColorCoords.x / parameters.size[0],
+                                        transformedColorCoords.y / parameters.size[1]);
+            const float4 color = mix(mix(parameters.colors[0], parameters.colors[2], blend.y),
+                                     mix(parameters.colors[1], parameters.colors[3], blend.y),
+                                     blend.x);
+            out = singleColor(sample, target, feather, color);
             break;
         }
     }
 
+
     return out;
 }
 
@@ -147,7 +150,7 @@ gradient2(float sample,
           float4 fromColor,
           float4 toColor)
 {
-    float4 blendedColor = averageTwoColors(normalizedBlend, fromColor, toColor);
+    float4 blendedColor = mix(fromColor, toColor, normalizedBlend);
     float4 out = singleColor(sample, target, feather, blendedColor);
     return out;
 }
diff --git a/MetaballsSaver/MetaballsSaverView.swift b/MetaballsSaver/MetaballsSaverView.swift
index dc83a52..6b93725 100644
--- a/MetaballsSaver/MetaballsSaverView.swift
+++ b/MetaballsSaver/MetaballsSaverView.swift
@@ -14,7 +14,7 @@ import ScreenSaver
     private static func defaultParameters() -> Parameters {
         var p = Parameters()
         let defaults = UserDefaults.standard
-        let style = defaults.colorStyle ?? .gradient2Horizontal
+        let style = defaults.colorStyle ?? .gradient2
         p.colorStyle = style
         let color0 = defaults.color0 ?? Float4(0.50, 0.79, 1, 1)
         p.color0 = color0