diff --git a/ambient_occlusion/ao.playground/Resources/Shaders.metal b/ambient_occlusion/ao.playground/Resources/Shaders.txt
similarity index 100%
rename from ambient_occlusion/ao.playground/Resources/Shaders.metal
rename to ambient_occlusion/ao.playground/Resources/Shaders.txt
diff --git a/ambient_occlusion/ao.playground/Sources/MetalView.swift b/ambient_occlusion/ao.playground/Sources/MetalView.swift
index d4bd02e..f0115a2 100644
--- a/ambient_occlusion/ao.playground/Sources/MetalView.swift
+++ b/ambient_occlusion/ao.playground/Sources/MetalView.swift
@@ -17,7 +17,7 @@ public class MetalView: NSObject, MTKViewDelegate {
     }
     
     func registerShaders() {
-        guard let path = Bundle.main.path(forResource: "Shaders", ofType: "metal") else { return }
+        guard let path = Bundle.main.path(forResource: "Shaders", ofType: "txt") else { return }
         do {
             let input = try String(contentsOfFile: path, encoding: String.Encoding.utf8)
             let library = try device.makeLibrary(source: input, options: nil)
diff --git a/ambient_occlusion/ao.playground/contents.xcplayground b/ambient_occlusion/ao.playground/contents.xcplayground
index a93d484..63b6dd8 100644
--- a/ambient_occlusion/ao.playground/contents.xcplayground
+++ b/ambient_occlusion/ao.playground/contents.xcplayground
@@ -1,4 +1,4 @@
 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
-<playground version='5.0' target-platform='macos' executeOnSourceChanges='false'>
+<playground version='5.0' target-platform='macos'>
     <timeline fileName='timeline.xctimeline'/>
 </playground>
\ No newline at end of file
diff --git a/ch08/chapter08.playground/Resources/Shaders.metal b/ch08/chapter08.playground/Resources/Shaders.txt
similarity index 100%
rename from ch08/chapter08.playground/Resources/Shaders.metal
rename to ch08/chapter08.playground/Resources/Shaders.txt
diff --git a/ch08/chapter08.playground/Sources/MetalView.swift b/ch08/chapter08.playground/Sources/MetalView.swift
index 0423b27..345a544 100644
--- a/ch08/chapter08.playground/Sources/MetalView.swift
+++ b/ch08/chapter08.playground/Sources/MetalView.swift
@@ -29,7 +29,7 @@ public class MetalView: NSObject, MTKViewDelegate {
     }
     
     func registerShaders() {
-        let path = Bundle.main.path(forResource: "Shaders", ofType: "metal")
+        let path = Bundle.main.path(forResource: "Shaders", ofType: "txt")
         let input: String?
         let library: MTLLibrary
         let vert_func: MTLFunction
diff --git a/ch09/chapter09.playground/Resources/Shaders.metal b/ch09/chapter09.playground/Resources/Shaders.txt
similarity index 100%
rename from ch09/chapter09.playground/Resources/Shaders.metal
rename to ch09/chapter09.playground/Resources/Shaders.txt
diff --git a/ch09/chapter09.playground/Sources/MetalView.swift b/ch09/chapter09.playground/Sources/MetalView.swift
index b4b69ac..dee66c0 100755
--- a/ch09/chapter09.playground/Sources/MetalView.swift
+++ b/ch09/chapter09.playground/Sources/MetalView.swift
@@ -43,7 +43,7 @@ public class MetalView: NSObject, MTKViewDelegate {
     }
     
     func createPipeline() {
-        let path = Bundle.main.path(forResource: "Shaders", ofType: "metal")
+        let path = Bundle.main.path(forResource: "Shaders", ofType: "txt")
         let input: String?
         let library: MTLLibrary
         let vert_func: MTLFunction
diff --git a/ch10/chapter10.playground/Resources/Shaders.metal b/ch10/chapter10.playground/Resources/Shaders.txt
similarity index 100%
rename from ch10/chapter10.playground/Resources/Shaders.metal
rename to ch10/chapter10.playground/Resources/Shaders.txt
diff --git a/ch10/chapter10.playground/Sources/MetalView.swift b/ch10/chapter10.playground/Sources/MetalView.swift
index 082a3f9..7da0980 100755
--- a/ch10/chapter10.playground/Sources/MetalView.swift
+++ b/ch10/chapter10.playground/Sources/MetalView.swift
@@ -15,7 +15,7 @@ public class MetalView: NSObject, MTKViewDelegate {
     func registerShaders() {
         device = MTLCreateSystemDefaultDevice()!
         queue = device.makeCommandQueue()
-        let path = Bundle.main.path(forResource: "Shaders", ofType: "metal")
+        let path = Bundle.main.path(forResource: "Shaders", ofType: "txt")
         do {
             let input = try String(contentsOfFile: path!, encoding: String.Encoding.utf8)
             let library = try device.makeLibrary(source: input, options: nil)
diff --git a/ch11/chapter11.playground/Resources/Shaders.metal b/ch11/chapter11.playground/Resources/Shaders.txt
similarity index 100%
rename from ch11/chapter11.playground/Resources/Shaders.metal
rename to ch11/chapter11.playground/Resources/Shaders.txt
diff --git a/ch11/chapter11.playground/Sources/MetalView.swift b/ch11/chapter11.playground/Sources/MetalView.swift
index 411a03e..9bcbe68 100755
--- a/ch11/chapter11.playground/Sources/MetalView.swift
+++ b/ch11/chapter11.playground/Sources/MetalView.swift
@@ -15,7 +15,7 @@ public class MetalView: NSObject, MTKViewDelegate {
   func registerShaders() {
     device = MTLCreateSystemDefaultDevice()!
     queue = device.makeCommandQueue()
-    let path = Bundle.main.path(forResource: "Shaders", ofType: "metal")
+    let path = Bundle.main.path(forResource: "Shaders", ofType: "txt")
     do {
       let input = try String(contentsOfFile: path!, encoding: String.Encoding.utf8)
       let library = try device.makeLibrary(source: input, options: nil)
diff --git a/ch12/chapter12.playground/Resources/Shaders.metal b/ch12/chapter12.playground/Resources/Shaders.txt
similarity index 100%
rename from ch12/chapter12.playground/Resources/Shaders.metal
rename to ch12/chapter12.playground/Resources/Shaders.txt
diff --git a/ch12/chapter12.playground/Sources/MetalView.swift b/ch12/chapter12.playground/Sources/MetalView.swift
index dfdae7d..a3eacf5 100755
--- a/ch12/chapter12.playground/Sources/MetalView.swift
+++ b/ch12/chapter12.playground/Sources/MetalView.swift
@@ -56,7 +56,7 @@ public class MetalView: MTKView, NSWindowDelegate {
     
     func registerShaders() {
         queue = device!.makeCommandQueue()
-        let path = Bundle.main.path(forResource: "Shaders", ofType: "metal")
+        let path = Bundle.main.path(forResource: "Shaders", ofType: "txt")
         do {
             let input = try String(contentsOfFile: path!, encoding: String.Encoding.utf8)
             let library = try device!.makeLibrary(source: input, options: nil)
diff --git a/ch13/chapter13.playground/Resources/Shaders.metal b/ch13/chapter13.playground/Resources/Shaders.txt
similarity index 100%
rename from ch13/chapter13.playground/Resources/Shaders.metal
rename to ch13/chapter13.playground/Resources/Shaders.txt
diff --git a/ch13/chapter13.playground/Sources/MetalView.swift b/ch13/chapter13.playground/Sources/MetalView.swift
index d1595ab..594fe34 100755
--- a/ch13/chapter13.playground/Sources/MetalView.swift
+++ b/ch13/chapter13.playground/Sources/MetalView.swift
@@ -55,7 +55,7 @@ public class MetalView: MTKView, NSWindowDelegate {
     
     func registerShaders() {
         queue = device!.makeCommandQueue()
-        let path = Bundle.main.path(forResource: "Shaders", ofType: "metal")
+        let path = Bundle.main.path(forResource: "Shaders", ofType: "txt")
         do {
             let input = try String(contentsOfFile: path!, encoding: String.Encoding.utf8)
             let library = try device!.makeLibrary(source: input, options: nil)
diff --git a/ch14/chapter14.playground/Resources/Shaders.metal b/ch14/chapter14.playground/Resources/Shaders.txt
similarity index 100%
rename from ch14/chapter14.playground/Resources/Shaders.metal
rename to ch14/chapter14.playground/Resources/Shaders.txt
diff --git a/ch14/chapter14.playground/Sources/MetalView.swift b/ch14/chapter14.playground/Sources/MetalView.swift
index e66e923..e7847a1 100755
--- a/ch14/chapter14.playground/Sources/MetalView.swift
+++ b/ch14/chapter14.playground/Sources/MetalView.swift
@@ -43,7 +43,7 @@ public class MetalView: MTKView, NSWindowDelegate {
     
     func registerShaders() {
         queue = device!.makeCommandQueue()
-        let path = Bundle.main.path(forResource: "Shaders", ofType: "metal")
+        let path = Bundle.main.path(forResource: "Shaders", ofType: "txt")
         do {
             let input = try String(contentsOfFile: path!, encoding: String.Encoding.utf8)
             let library = try device!.makeLibrary(source: input, options: nil)
diff --git a/ch15/chapter15.playground/Resources/Shaders.metal b/ch15/chapter15.playground/Resources/Shaders.txt
similarity index 100%
rename from ch15/chapter15.playground/Resources/Shaders.metal
rename to ch15/chapter15.playground/Resources/Shaders.txt
diff --git a/ch15/chapter15.playground/Sources/MetalView.swift b/ch15/chapter15.playground/Sources/MetalView.swift
index b2081e0..e9f37cc 100755
--- a/ch15/chapter15.playground/Sources/MetalView.swift
+++ b/ch15/chapter15.playground/Sources/MetalView.swift
@@ -25,7 +25,7 @@ public class MetalView: NSObject, MTKViewDelegate {
     }
   
     func registerShaders() {
-        let path = Bundle.main.path(forResource: "Shaders", ofType: "metal")
+        let path = Bundle.main.path(forResource: "Shaders", ofType: "txt")
         do {
             let input = try String(contentsOfFile: path!, encoding: String.Encoding.utf8)
             let library = try device!.makeLibrary(source: input, options: nil)
diff --git a/ch17/chapter17.playground/Resources/Shaders.metal b/ch17/chapter17.playground/Resources/Shaders.txt
similarity index 100%
rename from ch17/chapter17.playground/Resources/Shaders.metal
rename to ch17/chapter17.playground/Resources/Shaders.txt
diff --git a/ch17/chapter17.playground/Sources/Render.swift b/ch17/chapter17.playground/Sources/Render.swift
index e5a6d48..a85ffd9 100644
--- a/ch17/chapter17.playground/Sources/Render.swift
+++ b/ch17/chapter17.playground/Sources/Render.swift
@@ -42,7 +42,7 @@ public class Render : NSObject, MTKViewDelegate {
     }
   
     class func buildRenderPipelineWithDevice(device: MTLDevice, view: MTKView) throws -> MTLRenderPipelineState {
-        guard let path = Bundle.main.path(forResource: "Shaders", ofType: "metal") else { fatalError() }
+        guard let path = Bundle.main.path(forResource: "Shaders", ofType: "txt") else { fatalError() }
         let input = try String(contentsOfFile: path, encoding: String.Encoding.utf8)
         let library = try device.makeLibrary(source: input, options: nil)
         let vertexFunction = library.makeFunction(name: "vertex_transform")
@@ -54,7 +54,7 @@ public class Render : NSObject, MTKViewDelegate {
         pipelineDescriptor.colorAttachments[0].pixelFormat = .bgra8Unorm
         return try device.makeRenderPipelineState(descriptor: pipelineDescriptor)
     }
-  
+    
     public func mtkView(_ view: MTKView, drawableSizeWillChange size: CGSize) {}
   
     public func draw(in view: MTKView) {
diff --git a/ch18/chapter18.playground/Resources/Shaders.txt b/ch18/chapter18.playground/Resources/Shaders.txt
new file mode 100644
index 0000000..0835d9c
--- /dev/null
+++ b/ch18/chapter18.playground/Resources/Shaders.txt
@@ -0,0 +1,16 @@
+
+#include <metal_stdlib>
+using namespace metal;
+kernel void k(texture2d<float,access::write> o[[texture(0)]],
+              uint2 gid[[thread_position_in_grid]]) {
+    int width = o.get_width();
+    int height = o.get_height();
+    float2 uv = float2(gid) / float2(width, height);
+    float3 color = mix(float3(1.0, 0.6, 0.1), float3(0.5, 0.8, 1.0), sqrt(1 - uv.y));
+    float2 q = uv - float2(0.67, 0.25);
+    float r = 0.2 + 0.1 * cos(atan2(q.x, q.y) * 9.0 + 20.0 * q.x);
+    color *= smoothstep(r, r + 0.01, length(q));
+    r = 0.03 + 0.002 * cos(120.0 * q.y) + exp(-50.0 * (1.0 - uv.y));
+    color *= 1.0 - (1.0 - smoothstep(r, r + 0.002, abs(q.x - 0.25 * sin(2.0 * q.y)))) * smoothstep(0.0,  0.1, q.y);
+    o.write(float4(color, 1.0), gid);
+}
diff --git a/ch18/chapter18.playground/Sources/MetalView.swift b/ch18/chapter18.playground/Sources/MetalView.swift
index 8c8373b..120f22a 100644
--- a/ch18/chapter18.playground/Sources/MetalView.swift
+++ b/ch18/chapter18.playground/Sources/MetalView.swift
@@ -13,7 +13,9 @@ public class MetalView: NSObject, MTKViewDelegate {
         view.colorPixelFormat = .bgra8Unorm
         device = MTLCreateSystemDefaultDevice()!
         commandQueue = device.makeCommandQueue()
-        let library = try! device.makeLibrary(source: shader, options: nil)
+        guard let path = Bundle.main.path(forResource: "Shaders", ofType: "txt") else { fatalError() }
+        let input = try! String(contentsOfFile: path, encoding: String.Encoding.utf8)
+        let library = try! device.makeLibrary(source: input, options: nil)
         let function = library.makeFunction(name:"k")!
         cps = try! device.makeComputePipelineState(function: function)
         
diff --git a/compute/compute.playground/Resources/Shaders.metal b/compute/compute.playground/Resources/Shaders.txt
similarity index 100%
rename from compute/compute.playground/Resources/Shaders.metal
rename to compute/compute.playground/Resources/Shaders.txt
diff --git a/compute/compute.playground/Sources/MetalView.swift b/compute/compute.playground/Sources/MetalView.swift
index 6ba430a..39ab8a6 100644
--- a/compute/compute.playground/Sources/MetalView.swift
+++ b/compute/compute.playground/Sources/MetalView.swift
@@ -18,7 +18,7 @@ public class Renderer: NSObject, MTKViewDelegate {
         queue = device.makeCommandQueue()
         let textureLoader = MTKTextureLoader(device: device)
         let url = Bundle.main.url(forResource: "nature", withExtension: "jpg")!
-        guard let file = Bundle.main.path(forResource: "Shaders", ofType: "metal") else { return }
+        guard let file = Bundle.main.path(forResource: "Shaders", ofType: "txt") else { return }
         do {
             let source = try String(contentsOfFile: file, encoding: String.Encoding.utf8)
             let library = try device.makeLibrary(source: source, options: nil)
diff --git a/compute/compute.playground/contents.xcplayground b/compute/compute.playground/contents.xcplayground
index b478c1d..faac376 100644
--- a/compute/compute.playground/contents.xcplayground
+++ b/compute/compute.playground/contents.xcplayground
@@ -1,2 +1,2 @@
 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
-<playground version='6.0' target-platform='macos' executeOnSourceChanges='false'/>
\ No newline at end of file
+<playground version='6.0' target-platform='macos'/>
\ No newline at end of file
diff --git a/memory/memory_1.playground/Contents.swift b/memory/memory_1.playground/Contents.swift
index 5096ea6..24400f5 100644
--- a/memory/memory_1.playground/Contents.swift
+++ b/memory/memory_1.playground/Contents.swift
@@ -11,7 +11,7 @@ guard let outBuffer = device.makeBuffer(bytes: myVector, length: length, options
 for (index, _) in myVector.enumerated() { myVector[index] = Float(index) }
 var inBuffer = device.makeBuffer(bytes: myVector, length: length, options: [])
 
-let path = Bundle.main.path(forResource: "memory", ofType: "metal")
+let path = Bundle.main.path(forResource: "memory", ofType: "txt")
 let input = try String(contentsOfFile: path!, encoding: String.Encoding.utf8)
 let library = try device.makeLibrary(source: input, options: nil)
 let function = library.makeFunction(name: "compute")!
diff --git a/memory/memory_1.playground/Resources/memory.metal b/memory/memory_1.playground/Resources/memory.txt
similarity index 100%
rename from memory/memory_1.playground/Resources/memory.metal
rename to memory/memory_1.playground/Resources/memory.txt
diff --git a/memory/memory_1.playground/contents.xcplayground b/memory/memory_1.playground/contents.xcplayground
index a93d484..63b6dd8 100644
--- a/memory/memory_1.playground/contents.xcplayground
+++ b/memory/memory_1.playground/contents.xcplayground
@@ -1,4 +1,4 @@
 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
-<playground version='5.0' target-platform='macos' executeOnSourceChanges='false'>
+<playground version='5.0' target-platform='macos'>
     <timeline fileName='timeline.xctimeline'/>
 </playground>
\ No newline at end of file
diff --git a/memory/memory_1.playground/timeline.xctimeline b/memory/memory_1.playground/timeline.xctimeline
index 8a9c7b3..eb4ad70 100644
--- a/memory/memory_1.playground/timeline.xctimeline
+++ b/memory/memory_1.playground/timeline.xctimeline
@@ -3,7 +3,7 @@
    version = "3.0">
    <TimelineItems>
       <LoggerValueHistoryTimelineItem
-         documentLocation = "file:///Users/mhorga/Desktop/metal/memory/memory_1.playground#CharacterRangeLen=2&amp;CharacterRangeLoc=1554&amp;EndingColumnNumber=14&amp;EndingLineNumber=32&amp;StartingColumnNumber=12&amp;StartingLineNumber=32&amp;Timestamp=528665184.878259"
+         documentLocation = "file:///Users/matcegiela/Code/Metal/metal/memory/memory_1.playground#CharacterRangeLen=2&amp;CharacterRangeLoc=1552&amp;EndingColumnNumber=14&amp;EndingLineNumber=32&amp;StartingColumnNumber=12&amp;StartingLineNumber=32&amp;Timestamp=683824809.957611"
          selectedRepresentationIndex = "0"
          shouldTrackSuperviewWidth = "NO">
       </LoggerValueHistoryTimelineItem>
diff --git a/particles/particle.playground/Resources/Shaders.metal b/particles/particle.playground/Resources/Shaders.txt
similarity index 100%
rename from particles/particle.playground/Resources/Shaders.metal
rename to particles/particle.playground/Resources/Shaders.txt
diff --git a/particles/particle.playground/Sources/MetalView.swift b/particles/particle.playground/Sources/MetalView.swift
index 4c786f5..e116a8e 100644
--- a/particles/particle.playground/Sources/MetalView.swift
+++ b/particles/particle.playground/Sources/MetalView.swift
@@ -17,7 +17,7 @@ public class MetalView: NSObject, MTKViewDelegate {
     }
     
     func registerShaders() {
-        guard let path = Bundle.main.path(forResource: "Shaders", ofType: "metal") else { return }
+        guard let path = Bundle.main.path(forResource: "Shaders", ofType: "txt") else { return }
         do {
             let input = try String(contentsOfFile: path, encoding: String.Encoding.utf8)
             let library = try device.makeLibrary(source: input, options: nil)
diff --git a/particles/particle2.playground/Resources/Shaders.metal b/particles/particle2.playground/Resources/Shaders.txt
similarity index 100%
rename from particles/particle2.playground/Resources/Shaders.metal
rename to particles/particle2.playground/Resources/Shaders.txt
diff --git a/particles/particle2.playground/Sources/MetalViewDelegate.swift b/particles/particle2.playground/Sources/MetalViewDelegate.swift
index 4ae81f5..9676a56 100644
--- a/particles/particle2.playground/Sources/MetalViewDelegate.swift
+++ b/particles/particle2.playground/Sources/MetalViewDelegate.swift
@@ -43,7 +43,7 @@ public class MetalViewDelegate: NSObject, MTKViewDelegate {
         initializeBuffers()
         let library: MTLLibrary
         do {
-            let path = Bundle.main.path(forResource: "Shaders", ofType: "metal")
+            let path = Bundle.main.path(forResource: "Shaders", ofType: "txt")
             let source = try String(contentsOfFile: path!, encoding: .utf8)
             library = try device.makeLibrary(source: source, options: nil)
             let descriptor = MTLRenderPipelineDescriptor()
diff --git a/particles/particle3.playground/Resources/Shaders.metal b/particles/particle3.playground/Resources/Shaders.txt
similarity index 100%
rename from particles/particle3.playground/Resources/Shaders.metal
rename to particles/particle3.playground/Resources/Shaders.txt
diff --git a/particles/particle3.playground/Sources/MetalView.swift b/particles/particle3.playground/Sources/MetalView.swift
index fc1f7b6..95f853e 100644
--- a/particles/particle3.playground/Sources/MetalView.swift
+++ b/particles/particle3.playground/Sources/MetalView.swift
@@ -35,7 +35,7 @@ public class MetalView: NSObject, MTKViewDelegate {
     func initializeMetal() {
         device = MTLCreateSystemDefaultDevice()
         queue = device.makeCommandQueue()
-        guard let path = Bundle.main.path(forResource: "Shaders", ofType: "metal") else { return }
+        guard let path = Bundle.main.path(forResource: "Shaders", ofType: "txt") else { return }
         do {
             let input = try String(contentsOfFile: path, encoding: String.Encoding.utf8)
             let library = try device.makeLibrary(source: input, options: nil)
diff --git a/raymarching/raymarching.playground/Resources/Shaders.metal b/raymarching/raymarching.playground/Resources/Shaders.txt
similarity index 100%
rename from raymarching/raymarching.playground/Resources/Shaders.metal
rename to raymarching/raymarching.playground/Resources/Shaders.txt
diff --git a/raymarching/raymarching.playground/Sources/MetalView.swift b/raymarching/raymarching.playground/Sources/MetalView.swift
index 4e93127..ee995e3 100755
--- a/raymarching/raymarching.playground/Sources/MetalView.swift
+++ b/raymarching/raymarching.playground/Sources/MetalView.swift
@@ -17,7 +17,7 @@ public class MetalView: NSObject, MTKViewDelegate {
     func registerShaders() {
         device = MTLCreateSystemDefaultDevice()!
         queue = device.makeCommandQueue()
-        let path = Bundle.main.path(forResource: "Shaders", ofType: "metal")
+        let path = Bundle.main.path(forResource: "Shaders", ofType: "txt")
         do {
             let input = try String(contentsOfFile: path!, encoding: String.Encoding.utf8)
             let library = try device.makeLibrary(source: input, options: nil)
diff --git a/shadows/shadows.playground/Resources/Shaders.metal b/shadows/shadows.playground/Resources/Shaders.txt
similarity index 100%
rename from shadows/shadows.playground/Resources/Shaders.metal
rename to shadows/shadows.playground/Resources/Shaders.txt
diff --git a/shadows/shadows.playground/Sources/MetalView.swift b/shadows/shadows.playground/Sources/MetalView.swift
index 6ffd9d2..3344444 100755
--- a/shadows/shadows.playground/Sources/MetalView.swift
+++ b/shadows/shadows.playground/Sources/MetalView.swift
@@ -17,7 +17,7 @@ public class MetalView: NSObject, MTKViewDelegate {
     }
   
     func registerShaders() {
-        guard let path = Bundle.main.path(forResource: "Shaders", ofType: "metal") else { return }
+        guard let path = Bundle.main.path(forResource: "Shaders", ofType: "txt") else { return }
         do {
             let input = try String(contentsOfFile: path, encoding: String.Encoding.utf8)
             let library = try device.makeLibrary(source: input, options: nil)
diff --git a/shadows/shadows2.playground/Resources/Shaders.metal b/shadows/shadows2.playground/Resources/Shaders.txt
similarity index 100%
rename from shadows/shadows2.playground/Resources/Shaders.metal
rename to shadows/shadows2.playground/Resources/Shaders.txt
diff --git a/shadows/shadows2.playground/Sources/MetalView.swift b/shadows/shadows2.playground/Sources/MetalView.swift
index d4bd02e..f0115a2 100644
--- a/shadows/shadows2.playground/Sources/MetalView.swift
+++ b/shadows/shadows2.playground/Sources/MetalView.swift
@@ -17,7 +17,7 @@ public class MetalView: NSObject, MTKViewDelegate {
     }
     
     func registerShaders() {
-        guard let path = Bundle.main.path(forResource: "Shaders", ofType: "metal") else { return }
+        guard let path = Bundle.main.path(forResource: "Shaders", ofType: "txt") else { return }
         do {
             let input = try String(contentsOfFile: path, encoding: String.Encoding.utf8)
             let library = try device.makeLibrary(source: input, options: nil)