Various improvements

.gitignore

@@ -0,0 +1,2 @@
+# User-specific xcconfig files
+Xcode-config/DEVELOPMENT_TEAM.xcconfig

AudioWaveformGraph.xcodeproj/project.pbxproj

@@ -7,6 +7,9 @@
 	objects = {
 
 /* Begin PBXBuildFile section */
+		3D29594227B2C7B300BA7C0A /* DEVELOPMENT_TEAM.template.xcconfig in Resources */ = {isa = PBXBuildFile; fileRef = 3D29593F27B2C7B300BA7C0A /* DEVELOPMENT_TEAM.template.xcconfig */; };
+		3D29594327B2C7B300BA7C0A /* DEVELOPMENT_TEAM.xcconfig in Resources */ = {isa = PBXBuildFile; fileRef = 3D29594027B2C7B300BA7C0A /* DEVELOPMENT_TEAM.xcconfig */; };
+		3D29594427B2C7B300BA7C0A /* Shared.xcconfig in Resources */ = {isa = PBXBuildFile; fileRef = 3D29594127B2C7B300BA7C0A /* Shared.xcconfig */; };
 		EF1512EB258BDA8000F064A6 /* UIKitExtras.swift in Sources */ = {isa = PBXBuildFile; fileRef = EF1512EA258BDA8000F064A6 /* UIKitExtras.swift */; };
 		EFC5909725840B1500E5D4B4 /* AppDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = EFC5909625840B1500E5D4B4 /* AppDelegate.swift */; };
 		EFC5909925840B1500E5D4B4 /* SceneDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = EFC5909825840B1500E5D4B4 /* SceneDelegate.swift */; };
@@ -29,6 +32,9 @@
 /* End PBXBuildFile section */
 
 /* Begin PBXFileReference section */
+		3D29593F27B2C7B300BA7C0A /* DEVELOPMENT_TEAM.template.xcconfig */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.xcconfig; path = DEVELOPMENT_TEAM.template.xcconfig; sourceTree = "<group>"; };
+		3D29594027B2C7B300BA7C0A /* DEVELOPMENT_TEAM.xcconfig */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.xcconfig; path = DEVELOPMENT_TEAM.xcconfig; sourceTree = "<group>"; };
+		3D29594127B2C7B300BA7C0A /* Shared.xcconfig */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.xcconfig; path = Shared.xcconfig; sourceTree = "<group>"; };
 		EF1512EA258BDA8000F064A6 /* UIKitExtras.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = UIKitExtras.swift; sourceTree = "<group>"; };
 		EFC5909325840B1500E5D4B4 /* AudioWaveformGraph.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = AudioWaveformGraph.app; sourceTree = BUILT_PRODUCTS_DIR; };
 		EFC5909625840B1500E5D4B4 /* AppDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AppDelegate.swift; sourceTree = "<group>"; };
@@ -64,13 +70,25 @@
 /* End PBXFrameworksBuildPhase section */
 
 /* Begin PBXGroup section */
+		3D29593E27B2C7B300BA7C0A /* Xcode-config */ = {
+			isa = PBXGroup;
+			children = (
+				3D29593F27B2C7B300BA7C0A /* DEVELOPMENT_TEAM.template.xcconfig */,
+				3D29594027B2C7B300BA7C0A /* DEVELOPMENT_TEAM.xcconfig */,
+				3D29594127B2C7B300BA7C0A /* Shared.xcconfig */,
+			);
+			path = "Xcode-config";
+			sourceTree = "<group>";
+		};
 		EFC5908A25840B1500E5D4B4 = {
 			isa = PBXGroup;
 			children = (
+				3D29593E27B2C7B300BA7C0A /* Xcode-config */,
 				EFC5909525840B1500E5D4B4 /* AudioWaveformGraph */,
 				EFC5909425840B1500E5D4B4 /* Products */,
 			);
 			sourceTree = "<group>";
+			usesTabs = 0;
 		};
 		EFC5909425840B1500E5D4B4 /* Products */ = {
 			isa = PBXGroup;
@@ -191,7 +209,10 @@
 			files = (
 				EFC590A325840B1700E5D4B4 /* LaunchScreen.storyboard in Resources */,
 				EFC590AC25840B7500E5D4B4 /* audio.mp3 in Resources */,
+				3D29594227B2C7B300BA7C0A /* DEVELOPMENT_TEAM.template.xcconfig in Resources */,
+				3D29594327B2C7B300BA7C0A /* DEVELOPMENT_TEAM.xcconfig in Resources */,
 				EFC590A025840B1700E5D4B4 /* Assets.xcassets in Resources */,
+				3D29594427B2C7B300BA7C0A /* Shared.xcconfig in Resources */,
 				EFC5909E25840B1500E5D4B4 /* Main.storyboard in Resources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
@@ -245,6 +266,7 @@
 /* Begin XCBuildConfiguration section */
 		EFC590A525840B1700E5D4B4 /* Debug */ = {
 			isa = XCBuildConfiguration;
+			baseConfigurationReference = 3D29594127B2C7B300BA7C0A /* Shared.xcconfig */;
 			buildSettings = {
 				ALWAYS_SEARCH_USER_PATHS = NO;
 				CLANG_ANALYZER_NONNULL = YES;
@@ -294,7 +316,7 @@
 				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
-				IPHONEOS_DEPLOYMENT_TARGET = 14.2;
+				IPHONEOS_DEPLOYMENT_TARGET = 12.0;
 				MTL_ENABLE_DEBUG_INFO = INCLUDE_SOURCE;
 				MTL_FAST_MATH = YES;
 				ONLY_ACTIVE_ARCH = YES;
@@ -306,6 +328,7 @@
 		};
 		EFC590A625840B1700E5D4B4 /* Release */ = {
 			isa = XCBuildConfiguration;
+			baseConfigurationReference = 3D29594127B2C7B300BA7C0A /* Shared.xcconfig */;
 			buildSettings = {
 				ALWAYS_SEARCH_USER_PATHS = NO;
 				CLANG_ANALYZER_NONNULL = YES;
@@ -349,7 +372,7 @@
 				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
-				IPHONEOS_DEPLOYMENT_TARGET = 14.2;
+				IPHONEOS_DEPLOYMENT_TARGET = 12.0;
 				MTL_ENABLE_DEBUG_INFO = NO;
 				MTL_FAST_MATH = YES;
 				SDKROOT = iphoneos;
@@ -366,9 +389,7 @@
 				ASSETCATALOG_COMPILER_GLOBAL_ACCENT_COLOR_NAME = AccentColor;
 				CODE_SIGN_ENTITLEMENTS = AudioWaveformGraph/AudioWaveformGraph.entitlements;
 				CODE_SIGN_STYLE = Automatic;
-				DEVELOPMENT_TEAM = 899AA7RGN5;
 				INFOPLIST_FILE = AudioWaveformGraph/Info.plist;
-				IPHONEOS_DEPLOYMENT_TARGET = 13.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",
@@ -388,9 +409,7 @@
 				ASSETCATALOG_COMPILER_GLOBAL_ACCENT_COLOR_NAME = AccentColor;
 				CODE_SIGN_ENTITLEMENTS = AudioWaveformGraph/AudioWaveformGraph.entitlements;
 				CODE_SIGN_STYLE = Automatic;
-				DEVELOPMENT_TEAM = 899AA7RGN5;
 				INFOPLIST_FILE = AudioWaveformGraph/Info.plist;
-				IPHONEOS_DEPLOYMENT_TARGET = 13.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",

AudioWaveformGraph/AppDelegate.swift

@@ -10,21 +10,29 @@ import UIKit
 @main
 class AppDelegate: UIResponder, UIApplicationDelegate {
 
-
+    var window: UIWindow?
 
     func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
+        if #available(iOS 13, *) {
+            // Do nothing / do things that should only be done for iOS 13.
+        } else {
+            // Do iOS 12 specific window setup.
+        }
+
         // Override point for customization after application launch.
         return true
     }
 
     // MARK: UISceneSession Lifecycle
 
+    @available(iOS 13, *)
     func application(_ application: UIApplication, configurationForConnecting connectingSceneSession: UISceneSession, options: UIScene.ConnectionOptions) -> UISceneConfiguration {
         // Called when a new scene session is being created.
         // Use this method to select a configuration to create the new scene with.
         return UISceneConfiguration(name: "Default Configuration", sessionRole: connectingSceneSession.role)
     }
 
+    @available(iOS 13, *)
     func application(_ application: UIApplication, didDiscardSceneSessions sceneSessions: Set<UISceneSession>) {
         // Called when the user discards a scene session.
         // If any sessions were discarded while the application was not running, this will be called shortly after application:didFinishLaunchingWithOptions.

AudioWaveformGraph/Graph/DataProvider.swift

@@ -53,8 +53,14 @@ class DataProvider {
             idx += hopSize
         }
 
-        summarySampleMax = vDSP.maximum(workingAvgSamples)
-        summarySampleMin = vDSP.minimum(workingAvgSamples)
+        if #available(iOS 13, *) {
+            summarySampleMax = vDSP.maximum(workingAvgSamples)
+            summarySampleMin = vDSP.minimum(workingAvgSamples)
+        }
+        else {
+            vDSP_maxv(workingAvgSamples, 1, &summarySampleMax, vDSP_Length(workingAvgSamples.count))
+            vDSP_minv(workingAvgSamples, 1, &summarySampleMin, vDSP_Length(workingAvgSamples.count))
+        }
 
         summarySamples = workingAvgSamples
 
@@ -65,11 +71,11 @@ class DataProvider {
     }
 
     func sample(at time: Double) -> Float {
-        guard let summarySamples = summarySamples else { return 0 }
-        var summarySampleIdx = Int(time / duration * Double(summarySamples.count))
+        // `time` can dip below 0 if rubber-banding to before the first or after the last sample while scrolling.
+        guard (0.0..<duration).contains(time) else { return 0 }
 
-        // fail safe
-        summarySampleIdx = min(summarySampleIdx, summarySamples.count - 1)
+        guard let summarySamples = summarySamples else { return 0 }
+        let summarySampleIdx = Int(time / duration * Double(summarySamples.count))
 
         return summarySamples[summarySampleIdx]
     }

AudioWaveformGraph/SceneDelegate.swift

@@ -7,6 +7,7 @@
 
 import UIKit
 
+@available(iOS 13, *)
 class SceneDelegate: UIResponder, UIWindowSceneDelegate {
 
     var window: UIWindow?

AudioWaveformGraph/Utilities/MathUtilities.swift

@@ -10,9 +10,11 @@ import Accelerate
 
 func fast_mean(_ a: [Float], startIdx: Int, endIdx: Int) -> Float {
     var mean: Float = 0
-    // todo: dangling pointer warning is safe in this case since it's never accessed outside of scope, but should be fixed
-    let ptr = UnsafePointer<Float>(a)
-    vDSP_meanv(ptr + startIdx, 1, &mean, UInt(endIdx - startIdx))
+
+    a.withUnsafeBufferPointer { bufferPointer in
+        let ptr = bufferPointer.baseAddress!
+        vDSP_meanv(ptr + startIdx, 1, &mean, UInt(endIdx - startIdx))
+    }
 
     return mean
 }

Xcode-config/DEVELOPMENT_TEAM.template.xcconfig

@@ -0,0 +1 @@
+DEVELOPMENT_TEAM = AB1234C5DE

Xcode-config/Shared.xcconfig

@@ -0,0 +1,51 @@
+DEVELOPMENT_TEAM = 899AA7RGN5
+
+#include? "DEVELOPMENT_TEAM.xcconfig"
+
+// Create the file DEVELOPMENT_TEAM.xcconfig
+// in the "Xcode-config" directory within the project directory
+// with the following build setting:
+// DEVELOPMENT_TEAM = [Your TeamID]
+
+// One way to find your Team ID is to set the “Development Team”
+// build setting (Xcode key: "DEVELOPMENT_TEAM") and have a look
+// at the “Source Control” changes (menu item “Commit…”/⌥⌘C).
+// Just make sure that this change doesn’t actually get commited.
+
+// You can also find your Team ID by logging into your Apple Developer account
+// and going to
+// https://developer.apple.com/account/#/membership
+// It should be listed under “Team ID”.
+
+// To set this system up for your own project,
+// copy the "Xcode-config" directory there,
+// add it to your Xcode project,
+// navigate to your project settings
+// (root icon in the Xcode Project Navigator)
+// click on the project icon there,
+// click on the “Info” tab
+// under “Configurations”
+// open the “Debug”, “Release”,
+// and any other build configurations you might have.
+// There you can set the pull-down menus in the
+// “Based on Configuration File” column to “Shared”.
+// Your work in Xcode is done.
+
+// Don’t forget to add the DEVELOPMENT_TEAM.xcconfig file to your .gitignore:
+// # User-specific xcconfig files
+// Xcode-config/DEVELOPMENT_TEAM.xcconfig
+// The two lines above are an example.
+// Please don’t copy the comment slashes over though.
+
+// You can and should now replace the “DevelopmentTeam = AB1234C5DE;” entries in
+// .xcodeproj/project.pbxproj
+// with “DevelopmentTeam = "";”
+// They would otherwise override the Team ID set via this config file and its include.
+// Please note that .pbxproj files use straight quotes.
+
+// When you commit changes to the Xcode project file
+// after changing settings in “Signing & Capabilities”
+// Entries like these may appear in your file changes/commit diff preview:
+// CODE_SIGN_IDENTITY = …;
+// CODE_SIGN_STYLE = Manual/Automatic;
+// Please make sure not to commit them to source control.