Works

ImageCreation.xcodeproj/xcshareddata/xcschemes/ImageCreation.xcscheme

@@ -0,0 +1,85 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Scheme
+   LastUpgradeVersion = "1230"
+   version = "1.3">
+   <BuildAction
+      parallelizeBuildables = "YES"
+      buildImplicitDependencies = "YES">
+      <BuildActionEntries>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "YES"
+            buildForProfiling = "YES"
+            buildForArchiving = "YES"
+            buildForAnalyzing = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "FC74E21A2591889F00ACBBFF"
+               BuildableName = "ImageCreation"
+               BlueprintName = "ImageCreation"
+               ReferencedContainer = "container:ImageCreation.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
+      </BuildActionEntries>
+   </BuildAction>
+   <TestAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      shouldUseLaunchSchemeArgsEnv = "YES">
+      <Testables>
+      </Testables>
+   </TestAction>
+   <LaunchAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      launchStyle = "0"
+      useCustomWorkingDirectory = "NO"
+      ignoresPersistentStateOnLaunch = "NO"
+      debugDocumentVersioning = "YES"
+      debugServiceExtension = "internal"
+      allowLocationSimulation = "YES">
+      <BuildableProductRunnable
+         runnableDebuggingMode = "0">
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "FC74E21A2591889F00ACBBFF"
+            BuildableName = "ImageCreation"
+            BlueprintName = "ImageCreation"
+            ReferencedContainer = "container:ImageCreation.xcodeproj">
+         </BuildableReference>
+      </BuildableProductRunnable>
+      <EnvironmentVariables>
+         <EnvironmentVariable
+            key = "CGBITMAP_CONTEXT_LOG_ERRORS"
+            value = "1"
+            isEnabled = "YES">
+         </EnvironmentVariable>
+      </EnvironmentVariables>
+   </LaunchAction>
+   <ProfileAction
+      buildConfiguration = "Release"
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      savedToolIdentifier = ""
+      useCustomWorkingDirectory = "NO"
+      debugDocumentVersioning = "YES">
+      <BuildableProductRunnable
+         runnableDebuggingMode = "0">
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "FC74E21A2591889F00ACBBFF"
+            BuildableName = "ImageCreation"
+            BlueprintName = "ImageCreation"
+            ReferencedContainer = "container:ImageCreation.xcodeproj">
+         </BuildableReference>
+      </BuildableProductRunnable>
+   </ProfileAction>
+   <AnalyzeAction
+      buildConfiguration = "Debug">
+   </AnalyzeAction>
+   <ArchiveAction
+      buildConfiguration = "Release"
+      revealArchiveInOrganizer = "YES">
+   </ArchiveAction>
+</Scheme>

ImageCreation.xcodeproj/xcuserdata/jon.xcuserdatad/xcdebugger/Breakpoints_v2.xcbkptlist

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Bucket
+   uuid = "2AB13B00-E21B-4223-B6C7-A546E02EE846"
+   type = "1"
+   version = "2.0">
+</Bucket>

ImageCreation.xcodeproj/xcuserdata/jon.xcuserdatad/xcschemes/xcschememanagement.plist

@@ -10,5 +10,13 @@
 			<integer>0</integer>
 		</dict>
 	</dict>
+	<key>SuppressBuildableAutocreation</key>
+	<dict>
+		<key>FC74E21A2591889F00ACBBFF</key>
+		<dict>
+			<key>primary</key>
+			<true/>
+		</dict>
+	</dict>
 </dict>
 </plist>

ImageCreation/main.swift

@@ -1,3 +1,4 @@
+
 //
 //  main.swift
 //  ImageCreation
@@ -7,5 +8,113 @@
 
 import Foundation
 
-print("Hello, World!")
+let width = 2048
+let height = width
 
+let bitmapBytesPerRow = Int(width) * 4
+let bitmapByteCount = bitmapBytesPerRow * height
+
+enum Color {
+    case red
+    case green
+    case blue
+    case white
+}
+
+func nextColor(_ color: Color) -> Color {
+    switch color {
+    case .red:
+        return .green
+    case .green:
+        return .blue
+    case .blue:
+        return .white
+    case .white:
+        return .red
+    }
+}
+
+func redVal(_ currentColor: Color) -> UInt8 {
+    switch currentColor {
+    case .red:
+        return 255
+    case .green:
+        return 0
+    case .blue:
+        return 0
+    case .white:
+        return 255
+    }
+}
+
+func greenVal(_ currentColor: Color) -> UInt8 {
+    switch currentColor {
+    case .red:
+        return 0
+    case .green:
+        return 255
+    case .blue:
+        return 0
+    case .white:
+        return 255
+    }
+}
+
+func blueVal(_ currentColor: Color) -> UInt8 {
+    switch currentColor {
+    case .red:
+        return 0
+    case .green:
+        return 0
+    case .blue:
+        return 255
+    case .white:
+        return 255
+    }
+}
+
+func createPixels() -> [UInt8] {
+    var bitmapData = [UInt8](repeating: 0, count: bitmapByteCount)
+    
+    var currentColor = Color.red
+    
+    let rectWidth = 256 / 4
+    let rectHeight = Int(Double(rectWidth) * 1.5)
+    
+    for i in stride(from: 0, through: bitmapByteCount - 4, by: 4) {
+        bitmapData[i + 0] = redVal(currentColor)
+        bitmapData[i + 1] = greenVal(currentColor)
+        bitmapData[i + 2] = blueVal(currentColor)
+        bitmapData[i + 3] = 255 // alpha
+
+        if i % rectWidth == 0 && (i % (bitmapBytesPerRow * rectHeight)) != 0{
+            currentColor = nextColor(currentColor)
+        }
+    }
+    
+    return bitmapData
+}
+
+func createBitmap() -> CGContext {
+    
+    let colorSpace = CGColorSpaceCreateDeviceRGB()
+
+    var bitmapData = createPixels()
+    let bitmapInfo = CGBitmapInfo(rawValue: CGImageAlphaInfo.premultipliedLast.rawValue)
+
+    let context = CGContext.init(data: &bitmapData, width: width, height: height, bitsPerComponent: 8, bytesPerRow: bitmapBytesPerRow, space: colorSpace, bitmapInfo: bitmapInfo.rawValue)
+        
+    return context!
+}
+
+func buildImage() {
+    let context = createBitmap()
+    
+    let image = context.makeImage()
+    let url = URL(fileURLWithPath: "/Users/jon/Documents/testImage.png")
+    let dest = CGImageDestinationCreateWithURL(url as CFURL, kUTTypePNG, 1, nil)
+    CGImageDestinationAddImage(dest!, image!, nil)
+    CGImageDestinationFinalize(dest!)
+}
+
+buildImage()