Added Retro Rewind Quest Support

Launcher/WiiCompiled.Setup.Windows/QuestBuildService.cs

@@ -72,8 +72,16 @@ internal sealed class QuestBuildService
         var questRoot = Path.Combine(installation.Root, QuestDirectoryName);
         var kitDirectory = Path.Combine(questRoot, "kit");
         _reporter.Progress(InstallStages.QuestKit, "Reading the game kit from the Quest app...", 2);
-        var kitFingerprint = ExtractKit(apkPath, kitDirectory, cancellationToken);
-        _reporter.Diagnostic($"Quest game kit {kitFingerprint}");
+        var kit = ExtractKit(apkPath, kitDirectory, cancellationToken);
+        _reporter.Diagnostic($"Quest game kit {kit.Fingerprint} ({kit.Product})");
+        // A Retro Rewind app needs this installation's Retro Rewind translation, which only exists
+        // once the mod has been built here at least once.
+        if (kit.Product == "retro_rewind" && !HasRetroRewindShards(generated))
+        {
+            throw new InvalidOperationException(
+                "This Quest app is the Retro Rewind one, and this installation has no Retro Rewind " +
+                "translation. Install or repair Retro Rewind, then build for Quest again.");
+        }
 
         var toolchain = await EnsureToolchainAsync(questRoot, cancellationToken);
 
@@ -116,7 +124,7 @@ internal sealed class QuestBuildService
             TryDelete(temporaryOutput);
             throw;
         }
-        return new Result(outputPath, kitFingerprint, includeGameFiles, new FileInfo(outputPath).Length);
+        return new Result(outputPath, kit.Fingerprint, includeGameFiles, new FileInfo(outputPath).Length);
     }
 
     private void TryDelete(string path)
@@ -147,13 +155,24 @@ internal sealed class QuestBuildService
         }
     }
 
+    /// <summary>Whether emit-build-shards recorded a Retro Rewind translation in this workspace.</summary>
+    private static bool HasRetroRewindShards(string generated)
+    {
+        var shards = Path.Combine(generated, "build_shards", "shards.cmake");
+        return File.Exists(shards) &&
+               File.ReadAllText(shards).Contains("set(MKW_HAVE_RETRO_REWIND_SHARDS ON)", StringComparison.Ordinal);
+    }
+
     private static bool IsGameData(string directory) =>
         Directory.Exists(Path.Combine(directory, "files")) &&
         File.Exists(Path.Combine(directory, "sys", "fst.bin")) &&
         File.Exists(Path.Combine(directory, "sys", "main.dol"));
 
-    /// <summary>Extracts <c>assets/game_kit</c> from the Quest app's APK and returns its fingerprint.</summary>
-    internal static string ExtractKit(string apkPath, string destination, CancellationToken cancellationToken)
+    /// <summary>What the extracted kit says it builds: its fingerprint and product ("base" or "retro_rewind").</summary>
+    internal sealed record Kit(string Fingerprint, string Product);
+
+    /// <summary>Extracts <c>assets/game_kit</c> from the Quest app's APK and reads what it is for.</summary>
+    internal static Kit ExtractKit(string apkPath, string destination, CancellationToken cancellationToken)
     {
         const string prefix = "assets/game_kit/";
         if (Directory.Exists(destination)) Directory.Delete(destination, recursive: true);
@@ -179,10 +198,16 @@ internal sealed class QuestBuildService
             throw new InvalidDataException(
                 "This APK is not a WiiCompiled Quest app with a game kit. Choose the Quest app installed on the headset.");
         using var document = JsonDocument.Parse(File.ReadAllText(kitJson));
-        return document.RootElement.TryGetProperty("fingerprint", out var fingerprint) &&
-               fingerprint.ValueKind == JsonValueKind.String
-            ? fingerprint.GetString()!
-            : throw new InvalidDataException("The Quest app's game kit has no fingerprint.");
+        if (!document.RootElement.TryGetProperty("fingerprint", out var fingerprint) ||
+            fingerprint.ValueKind != JsonValueKind.String)
+        {
+            throw new InvalidDataException("The Quest app's game kit has no fingerprint.");
+        }
+        var product = document.RootElement.TryGetProperty("product", out var value) &&
+                      value.ValueKind == JsonValueKind.String
+            ? value.GetString()!
+            : "base";
+        return new Kit(fingerprint.GetString()!, product);
     }
 
     private async Task<Toolchain> EnsureToolchainAsync(string questRoot, CancellationToken cancellationToken)

Launcher/WiiCompiled.Setup.Windows/SelfTests.cs

@@ -369,14 +369,15 @@ internal static class SelfTests
                     using var writer = new StreamWriter(zip.CreateEntry(name).Open());
                     writer.Write(text);
                 }
-                Add("assets/game_kit/kit.json", "{\"schema\":1,\"fingerprint\":\"abc123\"}");
+                Add("assets/game_kit/kit.json", "{\"schema\":2,\"product\":\"retro_rewind\",\"fingerprint\":\"abc123\"}");
                 Add("assets/game_kit/include/memory.h", "#pragma once");
                 Add("assets/runtime_resources/dsp_coef.bin", "not the kit");
                 Add("lib/arm64-v8a/libSDL3.so", "not the kit");
             }
             var kit = Path.Combine(temp, "kit");
-            if (QuestBuildService.ExtractKit(apk, kit, CancellationToken.None) != "abc123")
-                throw new Exception("The kit fingerprint was not read.");
+            var extracted = QuestBuildService.ExtractKit(apk, kit, CancellationToken.None);
+            if (extracted.Fingerprint != "abc123" || extracted.Product != "retro_rewind")
+                throw new Exception("The kit fingerprint or product was not read.");
             if (!File.Exists(Path.Combine(kit, "include", "memory.h")) ||
                 Directory.GetFiles(kit, "*", SearchOption.AllDirectories).Length != 2)
                 throw new Exception("The kit extraction took the wrong files.");

android/Build-Quest.ps1

@@ -87,23 +87,27 @@ $apk = Get-ChildItem -Path $apkDir -Filter '*.apk' | Select-Object -First 1
 if (-not $apk) { throw "No APK under $apkDir" }
 Write-Host "APK: $($apk.FullName)"
 
-# The base APK must be distributable: no translated game inside, only the game kit.
-if ($Flavor -eq 'base') {
-    Add-Type -AssemblyName System.IO.Compression.FileSystem
-    $archive = [IO.Compression.ZipFile]::OpenRead($apk.FullName)
-    try {
-        $gameLibraries = @($archive.Entries | Where-Object { $_.FullName -match '^lib/[^/]+/libmain[^/]*\.so$' })
-        $hasKit = @($archive.Entries | Where-Object { $_.FullName -eq 'assets/game_kit/kit.json' }).Count -gt 0
-        $hasToolchain = @($archive.Entries | Where-Object { $_.FullName -eq 'assets/quest_toolchain/files.zip' }).Count -gt 0
-    } finally { $archive.Dispose() }
-    if ($gameLibraries.Count -gt 0) { throw "The APK contains a translated game library: $($gameLibraries.FullName -join ', ')" }
-    if (-not $hasKit) { throw 'The APK has no game kit (assets/game_kit/kit.json)' }
-    if (-not $hasToolchain) { throw 'The APK has no build toolchain (assets/quest_toolchain/files.zip)' }
-}
+# Every APK must be distributable: no translated game inside, only the game kit. The toolchain
+# that builds one on the headset travels in the base APK only.
+Add-Type -AssemblyName System.IO.Compression.FileSystem
+$archive = [IO.Compression.ZipFile]::OpenRead($apk.FullName)
+try {
+    $gameLibraries = @($archive.Entries | Where-Object { $_.FullName -match '^lib/[^/]+/libmain[^/]*\.so$' })
+    $hasKit = @($archive.Entries | Where-Object { $_.FullName -eq 'assets/game_kit/kit.json' }).Count -gt 0
+    $hasToolchain = @($archive.Entries | Where-Object { $_.FullName -eq 'assets/quest_toolchain/files.zip' }).Count -gt 0
+} finally { $archive.Dispose() }
+if ($gameLibraries.Count -gt 0) { throw "The APK contains a translated game library: $($gameLibraries.FullName -join ', ')" }
+if (-not $hasKit) { throw 'The APK has no game kit (assets/game_kit/kit.json)' }
+if ($Flavor -eq 'base' -and -not $hasToolchain) { throw 'The APK has no build toolchain (assets/quest_toolchain/files.zip)' }
+if ($Flavor -ne 'base' -and $hasToolchain) { throw 'Only the base APK carries the on-headset build toolchain' }
 
 if ($Install) {
     $adb = Join-Path $sdkRoot 'platform-tools\adb.exe'
     & $adb install -r $apk.FullName
     if ($LASTEXITCODE -ne 0) { throw "adb install failed ($LASTEXITCODE)" }
-    Write-Host 'Installed. Build the game with Build on this Quest in the launcher, or on this PC with android/Build-QuestGame.ps1 -Install.'
+    if ($Flavor -eq 'base') {
+        Write-Host 'Installed. Build the game with Build on this Quest in the launcher, or on this PC with android/Build-QuestGame.ps1 -Install.'
+    } else {
+        Write-Host "Installed. Build its game on this PC with android/Build-QuestGame.ps1 -Flavor $Flavor -Install."
+    }
 }

android/Build-QuestGame.ps1

@@ -13,7 +13,8 @@
 # downloaded, the toolkit's ninja and the workspace's recomp.yml.
 #
 # -Generated is the translator output (the dev workspace's generated/ by default). -Kit is the game
-# kit the Quest app carries; it defaults to the one the last APK build exported. -Data adds the
+# kit the Quest app carries; it defaults to the one the last APK build of -Flavor (base or
+# retroRewind, whose translation must include the mod) exported. -Data adds the
 # extracted disc (the directory holding sys/ and files/) so the headset needs nothing else.
 # -Install pushes the package into the app's Import folder over adb, where the launcher picks it
 # up the next time it opens.
@@ -30,6 +31,7 @@ param(
     [string]$Sysroot = '',
     [string]$Ninja = '',
     [string]$BuiltBy = 'android/Build-QuestGame.ps1',
+    [ValidateSet('base', 'retroRewind')] [string]$Flavor = 'base',
     [int]$TranslatedJobs = 0,
     [switch]$Install
 )
@@ -40,15 +42,18 @@ $root = $PSScriptRoot
 $workspace = (Resolve-Path (Join-Path $root '..')).Path
 if (-not $Generated) { $Generated = Join-Path $workspace '.scratch\vr-build-workspace\BuildWorkspace\generated' }
 if (-not $Manifest) { $Manifest = Join-Path $workspace 'projects\mkwii\recomp.yml' }
-if (-not $BuildDir) { $BuildDir = Join-Path $root 'app\build\questGame' }
+if (-not $BuildDir) { $BuildDir = Join-Path $root "app\build\questGame\$Flavor" }
 if (-not $Kit) {
-    # The kit the last APK build packaged (the exportBase*QuestGameKit tasks), so the game
-    # matches the app it will be imported into.
+    # The kit this flavour's last APK build packaged (its export<Flavor>*QuestGameKit task), so the
+    # game matches the app it will be imported into.
+    $exportTask = 'export' + $Flavor.Substring(0, 1).ToUpper() + $Flavor.Substring(1)
     $Kit = Get-ChildItem -Path (Join-Path $root 'app\build\generated') -Filter kit.json -Recurse -ErrorAction SilentlyContinue |
-        Where-Object { $_.Directory.Name -eq 'game_kit' } |
+        Where-Object { $_.Directory.Name -eq 'game_kit' -and $_.FullName -like "*$exportTask*" } |
         Sort-Object LastWriteTime -Descending | Select-Object -First 1 | ForEach-Object { $_.DirectoryName }
 }
-if (-not $Kit -or -not (Test-Path (Join-Path $Kit 'kit.json'))) { throw 'No game kit; run Build-Quest.ps1 first or pass -Kit' }
+if (-not $Kit -or -not (Test-Path (Join-Path $Kit 'kit.json'))) {
+    throw "No $Flavor game kit; run Build-Quest.ps1 -Flavor $Flavor first, or pass -Kit"
+}
 if (-not (Test-Path (Join-Path $Generated 'build_shards\shards.cmake'))) { throw "No translated graph at $Generated" }
 
 $sdkRoot = if ($env:ANDROID_HOME) { $env:ANDROID_HOME } elseif ($env:ANDROID_SDK_ROOT) { $env:ANDROID_SDK_ROOT } else { Join-Path $env:LOCALAPPDATA 'Android\Sdk' }
@@ -91,7 +96,8 @@ Write-Host "Game package: $Output (kit $($game.kitFingerprint))"
 
 if ($Install) {
     $adb = Join-Path $sdkRoot 'platform-tools\adb.exe'
-    $import = '/sdcard/Android/data/org.wiicompiled.quest/files/WiiCompiledOpenXRVR/Import'
+    $package = if ($Flavor -eq 'retroRewind') { 'org.wiicompiled.quest.retrorewind' } else { 'org.wiicompiled.quest' }
+    $import = "/sdcard/Android/data/$package/files/WiiCompiledOpenXRVR/Import"
     # The launcher creates Import itself and must own it to remove imported packages (see
     # Run-Quest.ps1 on adb-created directories), so only push into one that exists.
     $exists = ((& $adb shell "test -d '$import' && echo yes") | Out-String).Trim()

android/Export-QuestGameKit.ps1

@@ -1,16 +1,17 @@
 # Exports the Quest game kit (see QuestGameKit.psm1) from a configured and built Android CMake
 # tree. android/app/build.gradle.kts runs this after the native build and packages the result as
-# the APK's game_kit assets.
+# the APK's game_kit assets, once per app flavour.
 #
-#   powershell -ExecutionPolicy Bypass -File android/Export-QuestGameKit.ps1 -CMakeBinaryDir <dir> -OutputDir <dir> -LlvmStrip <llvm-strip>
+#   powershell -ExecutionPolicy Bypass -File android/Export-QuestGameKit.ps1 -CMakeBinaryDir <dir> -OutputDir <dir> -LlvmStrip <llvm-strip> [-Product base|retro_rewind]
 [CmdletBinding()]
 param(
     [Parameter(Mandatory)] [string]$CMakeBinaryDir,
     [Parameter(Mandatory)] [string]$OutputDir,
-    [Parameter(Mandatory)] [string]$LlvmStrip
+    [Parameter(Mandatory)] [string]$LlvmStrip,
+    [ValidateSet('base', 'retro_rewind')] [string]$Product = 'base'
 )
 $ErrorActionPreference = 'Stop'
 Import-Module (Join-Path $PSScriptRoot 'QuestGameKit.psm1') -Force
 $repo = (Resolve-Path (Join-Path $PSScriptRoot '..')).Path
-$fingerprint = Export-QuestGameKit -CMakeBinaryDir $CMakeBinaryDir -OutputDir $OutputDir -RepoRoot $repo -LlvmStrip $LlvmStrip
-Write-Host "Quest game kit $fingerprint -> $OutputDir"
+$fingerprint = Export-QuestGameKit -CMakeBinaryDir $CMakeBinaryDir -OutputDir $OutputDir -RepoRoot $repo -LlvmStrip $LlvmStrip -Product $Product
+Write-Host "Quest game kit ($Product) $fingerprint -> $OutputDir"

android/Prepare-QuestToolchain.ps1

@@ -271,6 +271,11 @@ function Publish-Translator([string]$Destination, [string]$Work) {
         & (Join-Path $env:SystemRoot 'System32\robocopy.exe') (Join-Path $repo $tree) (Join-Path $stage $tree) /E /XD bin obj /NFL /NDL /NJH /NJS /NP | Out-Null
         if ($LASTEXITCODE -ge 8) { throw "Staging $tree failed (robocopy $LASTEXITCODE)" }
     }
+    # Build output the checkout may hold for another target framework would be picked up here and
+    # make the retargeted publish resolve the wrong references.
+    Get-ChildItem -Recurse -Directory $stage |
+        Where-Object { $_.Name -eq 'bin' -or $_.Name -eq 'obj' } |
+        ForEach-Object { if (Test-Path $_.FullName) { Remove-Item -Recurse -Force $_.FullName } }
     foreach ($project in Get-ChildItem -Recurse -Filter *.csproj $stage) {
         $text = [IO.File]::ReadAllText($project.FullName)
         $retargeted = $text.Replace('<TargetFramework>net8.0</TargetFramework>', '<TargetFramework>net10.0</TargetFramework>')

android/QuestGameKit.psm1

@@ -8,12 +8,14 @@
 # exported from CMake's own build graph so its flags and link order cannot drift from a normal
 # build:
 #
-#  * the link line of mkw_quest_kit_probe (runtime/cmake/PublicProducts.cmake), which is
-#    WiiCompiled without the game, becomes kit.json's link inputs, with {game:*} markers where
-#    the game's objects sat in WiiCompiled's own link;
+#  * the link line of the flavour's probe (runtime/cmake/PublicProducts.cmake), which is that
+#    product without any translated code, becomes kit.json's link inputs, with {game:*} markers
+#    where the game's objects sat in the product's own link;
 #  * the compile commands CMake recorded for one source of each generated kind (translated shard,
 #    registration shard, disc-generated runtime source, blob assembly) become kit.json's
-#    compile flags, with include paths reduced to the kit's copy of runtime/include.
+#    compile flags, with include paths reduced to the kit's copy of runtime/include;
+#  * kit.json's "sources" says which of the translator's build_shards lists fill each slot, so a
+#    builder never has to know which flavour it is building.
 #
 # Placeholders in kit.json: {kit} the extracted kit, {sysroot} the NDK sysroot the compiler
 # uses, {workspace} the directory holding the translator's generated/ tree.
@@ -22,9 +24,42 @@
 
 Set-StrictMode -Version Latest
 
-$script:KitSchema = 1
+$script:KitSchema = 2
 $script:GameSchema = 1
 
+# What each app flavour's kit is made of. Slots name the game's objects in the probe's link line,
+# and Sources says which of the translator's build_shards lists ("@NAME") or generated files fill
+# each of them, in link order. Retro Rewind adds a slot: the mod's own shards and the
+# profile-sensitive base shards it replaces the base flavour's with, linked as objects rather
+# than through the base archive.
+$script:KitProfiles = @{
+    base = @{
+        Probe = 'libmkw_quest_kit_probe'
+        ProductObjectPattern = '/base_product\.cpp\.o$'
+        RegistrationPattern = '/build_shards/base_registration/[^/]+\.cpp$'
+        Slots = @('runtime', 'product', 'translated')
+        Sources = [ordered]@{
+            runtime = @('{workspace}/generated/data_sections_init.cpp', '{workspace}/generated/guest_symbol_table.cpp',
+                '{workspace}/generated/data_sections_init_blobs.S')
+            product = @('@MKW_BASE_REGISTRATION_SOURCES')
+            translated = @('@MKW_BASE_COMMON_SHARDS', '@MKW_BASE_PORTABLE_SENSITIVE_SHARDS')
+        }
+    }
+    retro_rewind = @{
+        Probe = 'libmkw_quest_kit_probe_retro'
+        ProductObjectPattern = '/retro_rewind_product\.cpp\.o$'
+        RegistrationPattern = '/build_shards/retro_rewind_registration/[^/]+\.cpp$'
+        Slots = @('runtime', 'product', 'mod', 'translated')
+        Sources = [ordered]@{
+            runtime = @('{workspace}/generated/data_sections_init.cpp', '{workspace}/generated/guest_symbol_table.cpp',
+                '{workspace}/generated/data_sections_init_blobs.S')
+            product = @('@MKW_RETRO_REGISTRATION_SOURCES')
+            mod = @('@MKW_RETRO_PORTABLE_SENSITIVE_SHARDS', '@MKW_RETRO_MOD_SHARDS', '@MKW_RETRO_EXTRA_SOURCES')
+            translated = @('@MKW_BASE_COMMON_SHARDS')
+        }
+    }
+}
+
 function ConvertTo-ForwardPath([string]$Path) {
     return [IO.Path]::GetFullPath($Path).Replace('\', '/').TrimEnd('/')
 }
@@ -165,7 +200,7 @@ function Split-DriverCommand([string]$Line) {
 # sysroot/ and lib/clang/), {output}, and {game:runtime}, {game:product}, {game:translated}, each
 # replaced by its object files (the translated ones already sit inside --start-lib/--end-lib).
 function Get-KitLldArguments {
-    param([string]$ClangCxx, [string]$KitDir, [string[]]$Flags, [string[]]$Inputs)
+    param([string]$ClangCxx, [string]$KitDir, [string[]]$Flags, [string[]]$Inputs, [string[]]$Slots)
     $kit = ConvertTo-ForwardPath $KitDir
     $ndk = ConvertTo-ForwardPath (Join-Path (Split-Path -Parent $ClangCxx) '..')
     # Forward slashes throughout: clang reads response files with GNU quoting, where '\' escapes.
@@ -173,7 +208,7 @@ function Get-KitLldArguments {
     New-Item -ItemType Directory $probe | Out-Null
     try {
         $markers = [ordered]@{}
-        foreach ($slot in 'runtime', 'product', 'translated') {
+        foreach ($slot in $Slots) {
             $markers[$slot] = ConvertTo-ForwardPath (Join-Path $probe "game_$slot.o")
             [IO.File]::WriteAllBytes($markers[$slot], [byte[]]@())
         }
@@ -182,12 +217,12 @@ function Get-KitLldArguments {
         foreach ($flag in $Flags) { $arguments.Add((& $real $flag)) }
         $arguments.Add('-o'); $arguments.Add("$probe/libmain.so")
         foreach ($linkInput in $Inputs) {
-            switch ($linkInput) {
-                '{game:runtime}' { $arguments.Add($markers.runtime) }
-                '{game:product}' { $arguments.Add($markers.product) }
-                '{game:translated}' { $arguments.Add('-Wl,--start-lib'); $arguments.Add($markers.translated); $arguments.Add('-Wl,--end-lib') }
-                default { $arguments.Add((& $real $linkInput)) }
-            }
+            $slot = [regex]::Match($linkInput, '^\{game:(\w+)\}$').Groups[1].Value
+            if (-not $slot) { $arguments.Add((& $real $linkInput)); continue }
+            # Only the base archive's slot keeps archive semantics; the rest are plain objects.
+            if ($slot -eq 'translated') { $arguments.Add('-Wl,--start-lib') }
+            $arguments.Add($markers[$slot])
+            if ($slot -eq 'translated') { $arguments.Add('-Wl,--end-lib') }
         }
         $rsp = Join-Path $probe 'link.rsp'
         [IO.File]::WriteAllText($rsp, (($arguments | ForEach-Object { ConvertTo-QuotedArgument $_ }) -join "`n"), (New-Object Text.UTF8Encoding $false))
@@ -218,7 +253,7 @@ function Get-KitLldArguments {
             if ($argument -match '[A-Za-z]:/') { throw "The kit link names a path outside the kit and the NDK: $argument" }
             $lld.Add($argument)
         }
-        foreach ($required in '{output}', '{game:runtime}', '{game:product}', '{game:translated}') {
+        foreach ($required in @('{output}') + @($Slots | ForEach-Object { "{game:$_}" })) {
             if (-not $lld.Contains($required)) { throw "The expanded kit link lacks $required" }
         }
         return , $lld.ToArray()
@@ -233,16 +268,18 @@ function Export-QuestGameKit {
         [Parameter(Mandatory)] [string]$CMakeBinaryDir,
         [Parameter(Mandatory)] [string]$OutputDir,
         [Parameter(Mandatory)] [string]$RepoRoot,
-        [Parameter(Mandatory)] [string]$LlvmStrip
+        [Parameter(Mandatory)] [string]$LlvmStrip,
+        [ValidateSet('base', 'retro_rewind')] [string]$Product = 'base'
     )
     $ErrorActionPreference = 'Stop'
     $binary = ConvertTo-ForwardPath $CMakeBinaryDir
     $runtimeInclude = ConvertTo-ForwardPath (Join-Path $RepoRoot 'runtime/include')
+    $kitProfile = $script:KitProfiles[$Product]
 
     # The probe's link edge: explicit inputs are the objects, LINK_LIBRARIES the archives.
     $ninja = [IO.File]::ReadAllText("$binary/build.ninja")
-    $edge = [regex]::Match($ninja, '(?m)^build (\S*libmkw_quest_kit_probe\.so): (\S+) ([^\r\n]*)\r?\n((?:  [^\r\n]*\r?\n)+)')
-    if (-not $edge.Success) { throw "No mkw_quest_kit_probe link edge in $binary/build.ninja" }
+    $edge = [regex]::Match($ninja, "(?m)^build (\S*$([regex]::Escape($kitProfile.Probe))\.so): (\S+) ([^\r\n]*)\r?\n((?:  [^\r\n]*\r?\n)+)")
+    if (-not $edge.Success) { throw "No $($kitProfile.Probe) link edge in $binary/build.ninja" }
     $explicit = ($edge.Groups[3].Value.Replace('$ ', '<ninja-space>') -split ' \|')[0]
     $objects = @($explicit -split ' ' | Where-Object { $_ } | ForEach-Object { ConvertFrom-NinjaPath $_.Replace('<ninja-space>', '$ ') })
     $vars = @{}
@@ -272,7 +309,7 @@ function Export-QuestGameKit {
     }
     $compile = [ordered]@{
         translated = & $flagsFor $translatedEntry
-        product = & $flagsFor (Find-Command '/build_shards/base_registration/[^/]+\.cpp$')
+        product = & $flagsFor (Find-Command $kitProfile.RegistrationPattern)
         runtime = & $flagsFor (Find-Command '/generated/data_sections_init\.cpp$')
         asm = & $flagsFor (Find-Command 'data_sections_init_blobs[^/]*\.S$')
     }
@@ -306,11 +343,17 @@ function Export-QuestGameKit {
     }
     for ($i = 0; $i -lt $objects.Count; $i++) {
         $inputs.Add((& $copy $objects[$i] 'objects'))
-        if ($i -eq $lastRuntime) { $inputs.Add('{game:runtime}') }
-        if ($objects[$i] -match '/base_product\.cpp\.o$') { $inputs.Add('{game:product}') }
+        if ($objects[$i] -match $kitProfile.ProductObjectPattern) { $inputs.Add('{game:product}') }
+        if ($i -eq $lastRuntime) {
+            $inputs.Add('{game:runtime}')
+            # Retro Rewind links the mod's own objects after the runtime's, as its CMake target does.
+            if ($kitProfile.Slots -contains 'mod') { $inputs.Add('{game:mod}') }
+        }
     }
-    if (-not $inputs.Contains('{game:runtime}') -or -not $inputs.Contains('{game:product}')) {
-        throw 'The probe link line lacks the runtime or product objects the game slots follow'
+    foreach ($slot in $kitProfile.Slots) {
+        if ($slot -ne 'translated' -and -not $inputs.Contains("{game:$slot}")) {
+            throw "The probe link line lacks the objects the {game:$slot} slot follows"
+        }
     }
     foreach ($token in ((ConvertFrom-NinjaPath $vars['LINK_LIBRARIES']) -split ' ' | Where-Object { $_ })) {
         if ($token.StartsWith('-')) { $inputs.Add($token); continue }
@@ -334,7 +377,7 @@ function Export-QuestGameKit {
     }
     $linkFlags.Add('-Wl,-soname,libmain.so')
     $lld = Get-KitLldArguments -ClangCxx (Join-Path (Split-Path -Parent $LlvmStrip) 'clang++.exe') -KitDir $OutputDir `
-        -Flags $linkFlags.ToArray() -Inputs $inputs.ToArray()
+        -Flags $linkFlags.ToArray() -Inputs $inputs.ToArray() -Slots $kitProfile.Slots
 
     # What the headset's translator needs besides the disc: the game manifest and symbol map, and
     # the runtime sources it indexes for native registrations, which must be the ones compiled into
@@ -346,11 +389,12 @@ function Export-QuestGameKit {
 
     $recipe = [ordered]@{
         schema = $script:KitSchema
-        product = 'base'
+        product = $Product
         output = 'libmain.so'
         target = $target
         runtimeIncludeFingerprint = Get-RuntimeIncludeFingerprint (Join-Path $OutputDir 'include')
         compile = $compile
+        sources = $kitProfile.Sources
         link = [ordered]@{ flags = $linkFlags.ToArray(); inputs = $inputs.ToArray(); lld = $lld }
     }
     $recipeJson = $recipe | ConvertTo-Json -Depth 8 -Compress
@@ -409,21 +453,37 @@ function Invoke-QuestGameBuild {
     $linkLines = @($recipe.link.flags | ForEach-Object { ConvertTo-QuotedArgument (& $expand $_) })
     [IO.File]::WriteAllText("$build/link.rsp", ($linkLines -join "`n"), (New-Object Text.UTF8Encoding $false))
 
-    # The Windows installer generates the blob assembly for PE/COFF; rewrite it for ELF exactly
-    # as runtime/cmake/PublicProducts.cmake does.
-    $blob = [IO.File]::ReadAllText("$generated/data_sections_init_blobs.S")
-    $elf = $blob.Replace('.section .rdata,"dr"', '.section .rodata,"a",@progbits')
-    if ($elf -ne $blob) { $elf += "`n.section .note.GNU-stack,`"`",@progbits`n" }
-    [IO.File]::WriteAllText("$build/data_sections_init_blobs_android.S", $elf, (New-Object Text.UTF8Encoding $false))
+    # The Windows installer generates blob assembly for PE/COFF; every one of them is rewritten for
+    # ELF exactly as runtime/cmake/PublicProducts.cmake does, into the build directory.
+    $toElf = {
+        param([string]$Source)
+        $text = [IO.File]::ReadAllText($Source)
+        $elf = $text.Replace('.section .rdata,"dr"', '.section .rodata,"a",@progbits')
+        if ($elf -ne $text) { $elf += "`n.section .note.GNU-stack,`"`",@progbits`n" }
+        $rewritten = "$build/$([IO.Path]::GetFileNameWithoutExtension($Source))_android.S"
+        [IO.File]::WriteAllText($rewritten, $elf, (New-Object Text.UTF8Encoding $false))
+        return $rewritten
+    }
 
+    # Each slot's sources, as the recipe names them: a build_shards list ("@NAME") or one generated
+    # file.
     $shards = "$generated/build_shards/shards.cmake"
-    $sources = [ordered]@{
-        runtime = @("$generated/data_sections_init.cpp", "$generated/guest_symbol_table.cpp")
-        runtimeAsm = @("$build/data_sections_init_blobs_android.S")
-        product = @(Read-ShardList $shards 'MKW_BASE_REGISTRATION_SOURCES')
-        translated = @((Read-ShardList $shards 'MKW_BASE_COMMON_SHARDS') + (Read-ShardList $shards 'MKW_BASE_PORTABLE_SENSITIVE_SHARDS'))
+    $sources = [ordered]@{}
+    foreach ($slot in $recipe.sources.PSObject.Properties.Name) {
+        $slotSources = New-Object System.Collections.Generic.List[string]
+        foreach ($entry in $recipe.sources.$slot) {
+            if ($entry.StartsWith('@')) {
+                Read-ShardList $shards $entry.Substring(1) | ForEach-Object { $slotSources.Add($_) }
+            } else {
+                $slotSources.Add((& $expand $entry))
+            }
+        }
+        $sources[$slot] = @($slotSources | ForEach-Object { if ($_.EndsWith('.S')) { & $toElf $_ } else { $_ } })
     }
     if ($sources.translated.Count -eq 0) { throw "No translated shards in $shards" }
+    foreach ($slot in $sources.Keys) {
+        if ($sources[$slot].Count -eq 0) { throw "The $slot sources of a $($recipe.product) game are missing from $shards" }
+    }
 
     $ninjaText = New-Object System.Text.StringBuilder
     $escape = { param([string]$p) $p.Replace('$', '$$').Replace(':', '$:').Replace(' ', '$ ') }
@@ -432,37 +492,36 @@ function Invoke-QuestGameBuild {
     [void]$ninjaText.AppendLine("rule cxx`n  command = $(ConvertTo-QuotedArgument $ClangCxx) @`$flags -c `$in -o `$out`n  description = Compiling `$in")
     [void]$ninjaText.AppendLine("rule asm`n  command = $(ConvertTo-QuotedArgument $ClangC) @`$flags -c `$in -o `$out`n  description = Assembling `$in")
     [void]$ninjaText.AppendLine("rule link`n  command = $(ConvertTo-QuotedArgument $ClangCxx) @`$flags -o `$out @`$out.rsp`n  rspfile = `$out.rsp`n  rspfile_content = `$inputs`n  description = Linking `$out")
-    $objectsOf = @{ runtime = @(); product = @(); translated = @() }
+    $objectsOf = @{}
     $seen = @{}
-    foreach ($kind in 'runtime', 'runtimeAsm', 'product', 'translated') {
-        foreach ($source in $sources[$kind]) {
+    foreach ($slot in $sources.Keys) {
+        $objectsOf[$slot] = @()
+        foreach ($source in $sources[$slot]) {
             $stem = [IO.Path]::GetFileNameWithoutExtension($source)
             $object = "obj/$stem.o"
             if ($seen.ContainsKey($object)) { throw "Two generated sources share the object name $object" }
             $seen[$object] = $true
-            $rule = if ($kind -eq 'runtimeAsm') { 'asm' } else { 'cxx' }
-            $flags = switch ($kind) { 'runtimeAsm' { 'asm.rsp' } default { "$kind.rsp" } }
+            # Assembly is assembled; a mod shard compiles with the same flags as a translated one.
+            $assembly = $source.EndsWith('.S')
+            $rule = if ($assembly) { 'asm' } else { 'cxx' }
+            $flags = if ($assembly) { 'asm.rsp' } elseif ($slot -eq 'mod') { 'translated.rsp' } else { "$slot.rsp" }
             [void]$ninjaText.AppendLine("build $(& $escape $object): $rule $(& $escape $source)`n  flags = $(& $escape "$build/$flags")")
-            if ($kind -eq 'translated') { [void]$ninjaText.AppendLine('  pool = translated') }
-            $slot = if ($kind -eq 'runtimeAsm') { 'runtime' } else { $kind }
+            if ($slot -eq 'translated' -or $slot -eq 'mod') { [void]$ninjaText.AppendLine('  pool = translated') }
             $objectsOf[$slot] += "$build/$object"
         }
     }
     $linkInputs = New-Object System.Collections.Generic.List[string]
     foreach ($linkInput in $recipe.link.inputs) {
-        switch ($linkInput) {
-            '{game:runtime}' { $objectsOf.runtime | ForEach-Object { $linkInputs.Add($_) } }
-            '{game:product}' { $objectsOf.product | ForEach-Object { $linkInputs.Add($_) } }
-            '{game:translated}' {
-                # Archive semantics, as libmkw_base_shared.a has in a CMake build.
-                $linkInputs.Add('-Wl,--start-lib')
-                $objectsOf.translated | ForEach-Object { $linkInputs.Add($_) }
-                $linkInputs.Add('-Wl,--end-lib')
-            }
-            default { $linkInputs.Add((& $expand $linkInput)) }
-        }
+        $slot = [regex]::Match($linkInput, '^\{game:(\w+)\}$').Groups[1].Value
+        if (-not $slot) { $linkInputs.Add((& $expand $linkInput)); continue }
+        if (-not $objectsOf.ContainsKey($slot)) { throw "The kit recipe links a {game:$slot} slot it names no sources for" }
+        # The base shards keep the archive semantics libmkw_base_shared.a has in a CMake build;
+        # every other slot is linked as plain objects, as the product's own CMake target does.
+        if ($slot -eq 'translated') { $linkInputs.Add('-Wl,--start-lib') }
+        $objectsOf[$slot] | ForEach-Object { $linkInputs.Add($_) }
+        if ($slot -eq 'translated') { $linkInputs.Add('-Wl,--end-lib') }
     }
-    $allObjects = @($objectsOf.runtime + $objectsOf.product + $objectsOf.translated | ForEach-Object { & $escape $_.Substring($build.Length + 1) })
+    $allObjects = @($sources.Keys | ForEach-Object { $objectsOf[$_] } | ForEach-Object { & $escape $_.Substring($build.Length + 1) })
     $rspInputs = ($linkInputs | ForEach-Object { ConvertTo-QuotedArgument $_ }) -join ' '
     [void]$ninjaText.AppendLine("build libmain.so: link $($allObjects -join ' ')`n  flags = $(& $escape "$build/link.rsp")`n  inputs = $($rspInputs.Replace('$', '$$'))")
     [IO.File]::WriteAllText("$build/build.ninja", $ninjaText.ToString(), (New-Object Text.UTF8Encoding $false))

android/app/build.gradle.kts

@@ -130,6 +130,8 @@ android {
             // The APK carries the game kit, not the game: the player's libmain.so is built from
             // their own disc and loaded from private storage (see android/QuestGameKit.psm1).
             buildConfigField("boolean", "EXTERNAL_GAME", "true")
+            // And it carries the toolchain that builds it on the headset (Prepare-QuestToolchain.ps1).
+            buildConfigField("boolean", "ON_DEVICE_BUILD", "true")
             externalNativeBuild { cmake { targets += "mkw_quest_kit_probe" } }
         }
         create("retroRewind") {
@@ -138,10 +140,11 @@ android {
             versionNameSuffix = "-retro-rewind"
             buildConfigField("String", "MAIN_LIBRARY", "\"main_retro_rewind\"")
             buildConfigField("String", "PROFILE", "\"retro_rewind\"")
-            // Not moved to the game kit yet: this flavour still bundles its translated library,
-            // so a Retro Rewind APK is for local use only.
-            buildConfigField("boolean", "EXTERNAL_GAME", "false")
-            externalNativeBuild { cmake { targets += "RetroRewind" } }
+            buildConfigField("boolean", "EXTERNAL_GAME", "true")
+            // Retro Rewind is built on a PC and imported: building it on the headset would also
+            // need the mod's Code.pul and its content there, which the launcher cannot fetch yet.
+            buildConfigField("boolean", "ON_DEVICE_BUILD", "false")
+            externalNativeBuild { cmake { targets += "mkw_quest_kit_probe_retro" } }
         }
     }
 
@@ -170,8 +173,8 @@ android {
     packaging {
         jniLibs {
             useLegacyPackaging = false
-            // Built only to produce the game kit; its objects travel as assets/game_kit.
-            excludes += "**/libmkw_quest_kit_probe.so"
+            // Built only to produce each flavour's game kit; their objects travel as assets/game_kit.
+            excludes += "**/libmkw_quest_kit_probe*.so"
         }
     }
     lint {
@@ -201,6 +204,10 @@ abstract class ExportQuestGameKit : DefaultTask() {
     @get:Internal
     abstract val llvmStrip: RegularFileProperty
 
+    /** "base" or "retro_rewind": which product's kit this flavour carries. */
+    @get:Internal
+    abstract val product: Property<String>
+
     @get:Inject
     abstract val execOperations: ExecOperations
 
@@ -212,10 +219,11 @@ abstract class ExportQuestGameKit : DefaultTask() {
     @TaskAction
     fun export() {
         val app = appDir.get().asFile
+        val library = if (product.get() == "base") "libmkw_quest_kit_probe.so" else "libmkw_quest_kit_probe_retro.so"
         val probe = File(app, "build/intermediates/cxx").walkTopDown()
-            .filter { it.name == "libmkw_quest_kit_probe.so" && it.parentFile.name == "arm64-v8a" }
+            .filter { it.name == library && it.parentFile.name == "arm64-v8a" }
             .maxByOrNull { it.lastModified() }
-            ?: throw GradleException("No libmkw_quest_kit_probe.so; the native build did not produce the game kit probe")
+            ?: throw GradleException("No $library; the native build did not produce the game kit probe")
         val configuration = probe.parentFile.parentFile.parentFile // <BuildType>/<hash>
         val binaryDir = File(app, ".cxx/${configuration.parentFile.name}/${configuration.name}/arm64-v8a")
         if (!File(binaryDir, "build.ninja").isFile) throw GradleException("No CMake tree at $binaryDir")
@@ -224,6 +232,7 @@ abstract class ExportQuestGameKit : DefaultTask() {
             commandLine(
                 "powershell", "-NoProfile", "-ExecutionPolicy", "Bypass", "-File", script.get().asFile.path,
                 "-CMakeBinaryDir", binaryDir.path, "-OutputDir", kitDir.path, "-LlvmStrip", llvmStrip.get().asFile.path,
+                "-Product", product.get(),
             )
         }
     }
@@ -263,32 +272,36 @@ abstract class PrepareQuestToolchain : DefaultTask() {
 }
 
 androidComponents {
-    onVariants(selector().withFlavor("profile" to "base")) { variant ->
-        val prepareToolchain = tasks.register<PrepareQuestToolchain>(
-            "prepare${variant.name.replaceFirstChar { it.uppercase() }}QuestToolchain"
-        ) {
-            script.set(rootProject.layout.projectDirectory.file("Prepare-QuestToolchain.ps1"))
-            sources.from(script, rootProject.layout.projectDirectory.dir("toolchain"))
-            sources.from(fileTree(File(mkwRepoRoot, "translator/src")) { exclude("**/bin/**", "**/obj/**") })
-            sources.from(fileTree(File(mkwRepoRoot, "Launcher/WiiCompiled.Setup.Common")) { exclude("**/bin/**", "**/obj/**") })
-            val host = if (System.getProperty("os.name").startsWith("Windows")) "windows-x86_64" else "linux-x86_64"
-            ndkLlvm.set(sdkComponents.ndkDirectory.map { it.dir("toolchains/llvm/prebuilt/$host") })
-        }
-        variant.sources.assets?.addGeneratedSourceDirectory(prepareToolchain, PrepareQuestToolchain::outputDir)
+    onVariants { variant ->
+        val host = if (System.getProperty("os.name").startsWith("Windows")) "windows-x86_64" else "linux-x86_64"
         val capitalized = variant.name.replaceFirstChar { it.uppercase() }
-        // AGP packages every library in the CMake output directory, so a game library left over
-        // from a build that still linked the game would otherwise ship in the APK.
+        // Both flavours ship a kit instead of the game. AGP packages every library in the CMake
+        // output directory, so a game library left over from an earlier build would otherwise
+        // travel in the APK.
         variant.packaging.jniLibs.excludes.add("**/libmain*.so")
         val export = tasks.register<ExportQuestGameKit>("export${capitalized}QuestGameKit") {
             dependsOn("merge${capitalized}NativeLibs")
             appDir.set(layout.projectDirectory)
             script.set(rootProject.layout.projectDirectory.file("Export-QuestGameKit.ps1"))
-            val host = if (System.getProperty("os.name").startsWith("Windows")) "windows-x86_64" else "linux-x86_64"
+            product.set(if (variant.flavorName == "retroRewind") "retro_rewind" else "base")
             llvmStrip.set(sdkComponents.ndkDirectory.map {
                 it.file("toolchains/llvm/prebuilt/$host/bin/llvm-strip" + if (host.startsWith("windows")) ".exe" else "")
             })
         }
         variant.sources.assets?.addGeneratedSourceDirectory(export, ExportQuestGameKit::outputDir)
+
+        // Only the base flavour builds the game on the headset, so only it carries the toolchain:
+        // Retro Rewind also needs the mod's own content and translation, which is a PC build for now.
+        if (variant.flavorName != "retroRewind") {
+            val prepareToolchain = tasks.register<PrepareQuestToolchain>("prepare${capitalized}QuestToolchain") {
+                script.set(rootProject.layout.projectDirectory.file("Prepare-QuestToolchain.ps1"))
+                sources.from(script, rootProject.layout.projectDirectory.dir("toolchain"))
+                sources.from(fileTree(File(mkwRepoRoot, "translator/src")) { exclude("**/bin/**", "**/obj/**") })
+                sources.from(fileTree(File(mkwRepoRoot, "Launcher/WiiCompiled.Setup.Common")) { exclude("**/bin/**", "**/obj/**") })
+                ndkLlvm.set(sdkComponents.ndkDirectory.map { it.dir("toolchains/llvm/prebuilt/$host") })
+            }
+            variant.sources.assets?.addGeneratedSourceDirectory(prepareToolchain, PrepareQuestToolchain::outputDir)
+        }
     }
 }
 

android/app/src/main/cpp/CMakeLists.txt

@@ -51,7 +51,7 @@ add_subdirectory("${MKW_REPO_ROOT}/runtime" wiicompiled-runtime)
 
 # App-owned JNI glue lives in each product library SDLActivity loads, and in the game kit
 # probe (runtime/cmake/PublicProducts.cmake) whose objects the player's game is linked with.
-foreach(product IN ITEMS WiiCompiled RetroRewind mkw_quest_kit_probe)
+foreach(product IN ITEMS WiiCompiled RetroRewind mkw_quest_kit_probe mkw_quest_kit_probe_retro)
     if(TARGET ${product})
         target_sources(${product} PRIVATE "${CMAKE_CURRENT_LIST_DIR}/quest_surface_jni.cpp")
         target_include_directories(${product} PRIVATE "${MKW_REPO_ROOT}/aurora-main/include")

android/app/src/main/java/org/wiicompiled/quest/GameStorage.kt

@@ -17,6 +17,8 @@ object GameStorage {
     // Must match kApplicationDirectoryName in runtime/include/runtime_config.h.
     const val APP_DIRECTORY = "WiiCompiledOpenXRVR"
     const val DISC_DIRECTORY = "DATA"
+    /** The Retro Rewind pack the modded product reads (`[paths] retro_rewind_root`). */
+    const val MOD_DIRECTORY = "RetroRewind6"
 
     enum class DiscStatus { Missing, Incomplete, Ready }
 
@@ -26,6 +28,12 @@ object GameStorage {
 
     fun discDirectory(context: Context): File = File(gameRoot(context), DISC_DIRECTORY)
 
+    fun modDirectory(context: Context): File = File(gameRoot(context), MOD_DIRECTORY)
+
+    /** Whether this app needs the Retro Rewind pack and has it. Always true for the base game. */
+    fun modContentReady(context: Context): Boolean =
+        BuildConfig.PROFILE != "retro_rewind" || File(modDirectory(context), "Binaries/Code.pul").isFile
+
     fun configFile(context: Context): File = File(gameRoot(context), "Config.toml")
 
     fun logsDirectory(context: Context): File = File(gameRoot(context), "Logs")
@@ -60,22 +68,28 @@ object GameStorage {
         importDirectory(context).mkdirs()
         val config = configFile(context)
         if (!config.isFile) {
-            val disc = discDirectory(context).absolutePath
-            config.writeText(
-                """
-                # WiiCompiled Quest configuration. Edit with the launcher, the in-game panel or adb pull/push.
-                [paths]
-                dvd_root = "$disc"
-
-                [video]
-                widescreen = true
-                resolution_multiplier = 1.0
-
-                [vr]
-                enabled = true
-                render_scale = 1.0
-                """.trimIndent() + "\n",
+            // Written line by line: trimIndent runs after interpolation, so an interpolated line
+            // would take the indent off every other one.
+            val lines = mutableListOf(
+                "# WiiCompiled Quest configuration. Edit with the launcher, the in-game panel or adb pull/push.",
+                "[paths]",
+                "dvd_root = \"${discDirectory(context).absolutePath}\"",
             )
+            // The modded product reads its pack from retro_rewind_root, which sits next to DATA here.
+            if (BuildConfig.PROFILE == "retro_rewind") {
+                lines += "retro_rewind_root = \"${modDirectory(context).absolutePath}\""
+            }
+            lines += listOf(
+                "",
+                "[video]",
+                "widescreen = true",
+                "resolution_multiplier = 1.0",
+                "",
+                "[vr]",
+                "enabled = true",
+                "render_scale = 1.0",
+            )
+            config.writeText(lines.joinToString("\n", postfix = "\n"))
         }
         return gameRoot
     }

android/app/src/main/java/org/wiicompiled/quest/launcher/BuildRecipe.kt

@@ -9,10 +9,6 @@ import java.security.MessageDigest
  */
 object BuildRecipe {
 
-    /** The translated source lists emit-build-shards writes into shards.cmake, in link order. */
-    val TRANSLATED_LISTS = listOf("MKW_BASE_COMMON_SHARDS", "MKW_BASE_PORTABLE_SENSITIVE_SHARDS")
-    const val REGISTRATION_LIST = "MKW_BASE_REGISTRATION_SOURCES"
-
     /**
      * One argument of a response file for clang or lld on Android, which read them with GNU
      * quoting: a backslash escapes the next character.

android/app/src/main/java/org/wiicompiled/quest/launcher/GameBuild.kt

@@ -53,6 +53,7 @@ object GameBuild {
     }
 
     private const val TAG = "WiiCompiledLauncher"
+    private const val KIT_SCHEMA = 2
     private const val TOOLCHAIN_ASSETS = "quest_toolchain"
     private const val KIT_ASSETS = "game_kit"
     private const val MARKER = ".complete"
@@ -66,6 +67,9 @@ object GameBuild {
 
     /** Null on success, otherwise the message to show. */
     fun run(context: Context, reporter: Reporter, cancelled: () -> Boolean, finishing: () -> Unit): String? {
+        if (!BuildConfig.ON_DEVICE_BUILD) {
+            return "This app cannot build its game on the headset. Build it on a computer and use Import from computer."
+        }
         val disc = GameStorage.discDirectory(context)
         if (GameStorage.discStatus(context) != GameStorage.DiscStatus.Ready) {
             return "The game files (DATA) are needed to build the game. Select your disc image first."
@@ -120,6 +124,9 @@ object GameBuild {
             val kitFingerprint = GameLibrary.kitFingerprint(context) ?: return "This app carries no game kit."
             unpackKit(kitFingerprint)
             val recipe = JSONObject(File(kit, "kit.json").readText())
+            if (recipe.optInt("schema") != KIT_SCHEMA) {
+                return "This app's game kit is version ${recipe.optInt("schema")}, which this builder does not know."
+            }
             report(40, Step.Prepare)
             downloadNdk(JSONObject(context.assets.open("$TOOLCHAIN_ASSETS/${toolchainManifest.getString("ndk")}").reader().use { it.readText() }))
 
@@ -336,21 +343,42 @@ object GameBuild {
                 stamp.writeText(identity)
             }
 
-            val blob = File(generated, "data_sections_init_blobs.S")
-            val elfBlob = File(work, "data_sections_init_blobs_android.S")
-            val blobText = blob.readText()
-            val elfText = BuildRecipe.elfBlobAssembly(blobText)
-            if (!elfBlob.isFile || elfBlob.readText() != elfText) elfBlob.writeText(elfText)
+            // Blob assembly generated on Windows is rewritten for ELF, as PublicProducts.cmake does.
+            fun elfAssembly(source: File): File {
+                val rewritten = File(work, source.nameWithoutExtension + "_android.S")
+                val text = BuildRecipe.elfBlobAssembly(source.readText())
+                if (!rewritten.isFile || rewritten.readText() != text) rewritten.writeText(text)
+                return rewritten
+            }
 
+            // Which sources fill each link slot is the recipe's to say, so this builds either flavour.
             data class Job(val kind: String, val source: File, val slot: String)
             val jobs = ArrayList<Job>()
-            jobs += Job("runtime", File(generated, "data_sections_init.cpp"), "runtime")
-            jobs += Job("runtime", File(generated, "guest_symbol_table.cpp"), "runtime")
-            jobs += Job("asm", elfBlob, "runtime")
-            BuildRecipe.sourceList(shards, BuildRecipe.REGISTRATION_LIST).forEach { jobs += Job("product", File(it), "product") }
-            val translated = BuildRecipe.TRANSLATED_LISTS.flatMap { BuildRecipe.sourceList(shards, it) }
-            if (translated.isEmpty()) throw IOException("The translation produced no game code.")
-            translated.forEach { jobs += Job("translated", File(it), "translated") }
+            val sources = recipe.getJSONObject("sources")
+            for (slot in sources.keys()) {
+                val entries = sources.getJSONArray(slot)
+                val slotSources = ArrayList<File>()
+                for (i in 0 until entries.length()) {
+                    val entry = entries.getString(i)
+                    when {
+                        entry.startsWith("@") -> BuildRecipe.sourceList(shards, entry.substring(1)).forEach { slotSources += File(it) }
+                        else -> slotSources += File(BuildRecipe.expand(entry, mapOf("workspace" to workspace.absolutePath)))
+                    }
+                }
+                if (slotSources.isEmpty()) {
+                    throw IOException("The translation has no $slot sources for a ${recipe.getString("product")} game.")
+                }
+                // Assembly is assembled; a mod shard compiles with the same flags as a translated one.
+                slotSources.forEach { source ->
+                    val assembly = source.name.endsWith(".S")
+                    val kind = when {
+                        assembly -> "asm"
+                        slot == "mod" -> "translated"
+                        else -> slot
+                    }
+                    jobs += Job(kind, if (assembly) elfAssembly(source) else source, slot)
+                }
+            }
             if (jobs.map { BuildRecipe.objectName(it.source.path) }.toSet().size != jobs.size) {
                 throw IOException("Two generated sources share an object name.")
             }
@@ -361,7 +389,7 @@ object GameBuild {
                 "workspace" to workspace.absolutePath,
             )
             val compileFlags = recipe.getJSONObject("compile")
-            for (kind in listOf("runtime", "asm", "product", "translated")) {
+            for (kind in jobs.map { it.kind }.distinct()) {
                 val flags = compileFlags.getJSONArray(kind).let { array -> (0 until array.length()).map { BuildRecipe.expand(array.getString(it), values) } }
                 File(work, "$kind.rsp").writeText(BuildRecipe.responseFile(flags))
             }

android/app/src/main/java/org/wiicompiled/quest/launcher/LauncherActivity.kt

@@ -211,11 +211,12 @@ class LauncherActivity : Activity() {
         mainAction = when {
             running -> Action.Resume
             discStatus != GameStorage.DiscStatus.Ready -> Action.SelectDisc
-            gameStatus != GameLibrary.Status.Ready -> Action.BuildGame
+            gameStatus != GameLibrary.Status.Ready -> if (BuildConfig.ON_DEVICE_BUILD) Action.BuildGame else Action.ImportGame
             else -> Action.Play
         }
         secondaryAction = when {
             settingUp || running -> null
+            mainAction == Action.ImportGame -> null
             gameStatus != GameLibrary.Status.Ready || mainAction == Action.SelectDisc -> Action.ImportGame
             else -> null
         }
@@ -279,10 +280,14 @@ class LauncherActivity : Activity() {
             setup is GameSetup.State.Failed && building -> showBanner(getString(R.string.home_build_failed, setup.message), warning = true)
             setup is GameSetup.State.Failed -> showBanner(getString(R.string.home_setup_failed, setup.message), warning = true)
             discStatus == GameStorage.DiscStatus.Incomplete -> showBanner(getString(R.string.home_data_incomplete, disc), warning = true)
-            gameStatus == GameLibrary.Status.Stale -> showBanner(getString(R.string.home_game_stale), warning = true)
+            !GameStorage.modContentReady(this) ->
+                showBanner(getString(R.string.home_mod_missing, GameStorage.modDirectory(this).absolutePath), warning = true)
+            gameStatus == GameLibrary.Status.Stale ->
+                showBanner(getString(if (BuildConfig.ON_DEVICE_BUILD) R.string.home_game_stale else R.string.home_game_stale_pc), warning = true)
             gameStatus == GameLibrary.Status.Missing && discStatus == GameStorage.DiscStatus.Missing ->
-                showBanner(getString(R.string.home_setup_intro), warning = false)
-            gameStatus == GameLibrary.Status.Missing -> showBanner(getString(R.string.home_game_missing), warning = false)
+                showBanner(getString(if (BuildConfig.ON_DEVICE_BUILD) R.string.home_setup_intro else R.string.home_setup_intro_pc), warning = false)
+            gameStatus == GameLibrary.Status.Missing ->
+                showBanner(getString(if (BuildConfig.ON_DEVICE_BUILD) R.string.home_game_missing else R.string.home_game_missing_pc), warning = false)
             discStatus == GameStorage.DiscStatus.Missing -> showBanner(getString(R.string.home_data_missing, disc), warning = false)
             else -> showBanner(null)
         }
@@ -322,7 +327,7 @@ class LauncherActivity : Activity() {
 
     /** Builds the game on this headset from DATA, after saying what that takes. */
     private fun buildGame() {
-        if (GameSetup.isRunning || GameStorage.discStatus(this) != GameStorage.DiscStatus.Ready) return
+        if (!BuildConfig.ON_DEVICE_BUILD || GameSetup.isRunning || GameStorage.discStatus(this) != GameStorage.DiscStatus.Ready) return
         val message = if (GameLibrary.status(this) == GameLibrary.Status.Ready) R.string.home_build_replace_message else R.string.home_build_message
         confirm(R.string.home_build_title, message, R.string.home_build) {
             GameSetupService.startBuild(this)

android/app/src/main/java/org/wiicompiled/quest/launcher/SettingsPage.kt

@@ -282,11 +282,13 @@ class SettingsPage(
                 GameLibrary.Status.Missing -> activity.getString(R.string.about_game_missing)
             }
             info(R.string.about_game, gameText, stacked = true)
-            action(
-                R.string.home_build, R.string.about_build_helper, R.string.home_build,
-                enabled = !GameSetup.isRunning && GameStorage.discStatus(activity) == GameStorage.DiscStatus.Ready,
-            ) {
-                buildGame()
+            if (BuildConfig.ON_DEVICE_BUILD) {
+                action(
+                    R.string.home_build, R.string.about_build_helper, R.string.home_build,
+                    enabled = !GameSetup.isRunning && GameStorage.discStatus(activity) == GameStorage.DiscStatus.Ready,
+                ) {
+                    buildGame()
+                }
             }
             action(R.string.home_import, R.string.about_import_helper, R.string.home_import, enabled = !GameSetup.isRunning) {
                 importGame()

android/app/src/main/res/values/strings.xml

@@ -24,6 +24,9 @@
     <string name="home_setup_intro">Nothing from Mario Kart Wii comes with this app: the game is built from your own PAL (RMCP01) disc.\n\nOn this headset: copy your disc image (ISO, WBFS, RVZ…) here, for example into Download, press Select disc image, then Build on this Quest.\n\nWith a computer: in the WiiCompiled VR launcher, use Build for Quest with your disc image, copy the .wcgame file it makes to this headset, then press Import from computer.</string>
     <string name="home_game_missing">The game files are ready. Now build the game from them: Build on this Quest takes about 30–40 minutes on a Quest 3. With a computer, use Build for Quest in the WiiCompiled VR launcher instead, copy the .wcgame file to this headset and press Import from computer.</string>
     <string name="home_game_stale">This app was updated, so the game must be built again for it: press Build on this Quest, or use Build for Quest in the WiiCompiled VR launcher again and Import from computer.</string>
+    <string name="home_setup_intro_pc">Nothing from Mario Kart Wii or Retro Rewind comes with this app: the game is built from your own PAL (RMCP01) disc.\n\nCopy your disc image (ISO, WBFS, RVZ…) here, for example into Download, and press Select disc image. Then, on a computer, use Build for Quest in the WiiCompiled VR launcher with this app’s APK, copy the .wcgame file it makes to this headset and press Import from computer.</string>
+    <string name="home_game_missing_pc">The game files are ready. The game itself is built on a computer: in the WiiCompiled VR launcher, use Build for Quest with this app’s APK, copy the .wcgame file to this headset, then press Import from computer.</string>
+    <string name="home_game_stale_pc">This app was updated, so the game must be built again for it: use Build for Quest in the WiiCompiled VR launcher again, then Import from computer.</string>
     <string name="home_build">Build on this Quest</string>
     <string name="home_build_preparing">Preparing…</string>
     <string name="home_building">Building %1$d%%</string>
@@ -46,6 +49,7 @@
     <string name="home_replace_game_title">Replace the game?</string>
     <string name="home_replace_game_message">The game installed now stays until the new game file has been checked and completely imported.</string>
     <string name="home_data_incomplete">DATA is there but incomplete or unreadable. Select your disc image to extract it again, or copy the whole extracted partition (sys/ and files/, not just files/) to:\n%1$s</string>
+    <string name="home_mod_missing">The Retro Rewind pack is missing, so the game cannot start. Copy the RetroRewind6 folder (the one with Binaries, Tracks and Assets in it) to:\n%1$s</string>
     <string name="home_checking">Checking disc…</string>
     <string name="home_extracting">Extracting %1$d%%</string>
     <string name="home_finishing">Finishing…</string>

android/app/src/test/java/org/wiicompiled/quest/launcher/BuildRecipeTest.kt

@@ -22,6 +22,17 @@ class BuildRecipeTest {
         assertThrows(IllegalArgumentException::class.java) { BuildRecipe.expand("-I{workspace}", values) }
     }
 
+    @Test
+    fun expandsAnyLinkSlotTheRecipeNames() {
+        // Retro Rewind adds a mod slot; a builder only has to expand what the recipe lists.
+        val arguments = BuildRecipe.linkArguments(
+            listOf("{game:product}", "{game:mod}", "--start-lib", "{game:translated}", "--end-lib"),
+            emptyMap(),
+            mapOf("product" to listOf("/o/reg.o"), "mod" to listOf("/o/m1.o", "/o/m2.o"), "translated" to listOf("/o/base.o")),
+        )
+        assertEquals(listOf("/o/reg.o", "/o/m1.o", "/o/m2.o", "--start-lib", "/o/base.o", "--end-lib"), arguments)
+    }
+
     @Test
     fun expandsTheLinkSlotsInPlace() {
         val template = listOf("-o", "{output}", "{kit}/objects/001_a.o", "{game:runtime}", "--start-lib", "{game:translated}", "--end-lib", "-lm")
@@ -59,7 +70,10 @@ class BuildRecipeTest {
         )
         assertEquals(emptyList<String>(), BuildRecipe.sourceList(shards, "MKW_BASE_PORTABLE_SENSITIVE_SHARDS"))
         assertEquals(emptyList<String>(), BuildRecipe.sourceList(shards, "MKW_RETRO_MOD_SHARDS"))
-        assertEquals(listOf("C:/w/generated/build_shards/base_registration/registration_00.cpp"), BuildRecipe.sourceList(shards, BuildRecipe.REGISTRATION_LIST))
+        assertEquals(
+            listOf("C:/w/generated/build_shards/base_registration/registration_00.cpp"),
+            BuildRecipe.sourceList(shards, "MKW_BASE_REGISTRATION_SOURCES"),
+        )
     }
 
     @Test

docs/quest-port.md

@@ -234,11 +234,23 @@ The kit is exported from CMake's own build graph, so its flags cannot drift from
   this way had the same 61,975 defined and 785 undefined dynamic symbols, 29,995 translated
   functions, `NEEDED` list and soname as the CMake-built one, in 2.4 minutes.
 
-`Build-Quest.ps1` refuses a base APK that contains any `libmain*.so` or lacks the kit, and the
-base variant excludes `**/libmain*.so` from packaging, since AGP packages every library left in
-the CMake output directory. The `func_8…` symbols the kit's runtime objects define are
+`Build-Quest.ps1` refuses an APK that contains any `libmain*.so` or lacks the kit, and every
+variant excludes `**/libmain*.so` and the probes from packaging, since AGP packages every library
+left in the CMake output directory. The `func_8…` symbols the kit's runtime objects define are
 hand-written HLE overrides (`PPC_NATIVE_OVERRIDE_*` in `hle_stubs.h`), not translated code.
-The Retro Rewind flavour has not moved to the kit yet and still bundles its library.
+
+**Retro Rewind has its own kit** (`mkw_quest_kit_probe_retro`, RetroRewind without any translated
+code), so that APK ships no game either. It needs one more link slot than the base flavour, because
+the modded product links more kinds of translated code: `{game:runtime}` (the disc-generated
+sources), `{game:product}` (the mod's registration and dispatch shards), `{game:mod}` (the mod's own
+shards, the profile-sensitive base shards it replaces, and the mod's data patches) and
+`{game:translated}` (the shared base shards, with the archive semantics `libmkw_base_shared.a` has).
+Rather than teach each builder which flavour it is building, `kit.json` now carries a `sources`
+map naming the `shards.cmake` list behind each slot, and the builders just follow it (kit schema 2).
+Its game is built on a PC for now: building it on the headset would also need the mod's `Code.pul`
+and its 2 GB pack there, so only the base APK carries the on-device toolchain
+(`BuildConfig.ON_DEVICE_BUILD`). The Retro Rewind app writes `[paths] retro_rewind_root` into its
+first `Config.toml` and Home says so when that pack is missing.
 
 ### Game packages (.wcgame) and Import from computer
 
@@ -365,7 +377,8 @@ Android facts this design rests on, all measured on a Quest 3:
   another host.
 - `android/`: the Gradle project. `app/src/main/cpp/CMakeLists.txt` adds the
   repository's `runtime/` as a subdirectory with those Android choices;
-  flavours `base` and `retroRewind` pick the product target and library name.
+  flavours `base` and `retroRewind` each build their own game kit probe, and only `base` carries
+  the on-headset toolchain.
 - `android/nod-jni`: Gradle's `buildNodJni` task runs `cargo build --release
   --locked --target aarch64-linux-android` with the NDK's clang as linker and C
   compiler. `stageNodJni` puts `libnod_jni.so` into the APK's `arm64-v8a`
@@ -384,7 +397,8 @@ installer's `BuildWorkspace/generated`, produced by the normal Windows pipeline)
 powershell -ExecutionPolicy Bypass -File android/Prepare-QuestDependencies.ps1        # SDL3 3.4.4 AAR into android/app/libs
 powershell -ExecutionPolicy Bypass -File android/Build-Quest.ps1 -Install             # the app, its game kit and toolchain, debug-signed
 powershell -ExecutionPolicy Bypass -File android/Build-QuestGame.ps1 -Install         # your game, against that kit, into Import (or WheelWizard VR's Build for Quest)
-powershell -ExecutionPolicy Bypass -File android/Build-Quest.ps1 -Flavor retroRewind  # Retro Rewind (needs translate-mod output)
+powershell -ExecutionPolicy Bypass -File android/Build-Quest.ps1 -Flavor retroRewind  # Retro Rewind app and its kit (needs translate-mod output)
+powershell -ExecutionPolicy Bypass -File android/Build-QuestGame.ps1 -Flavor retroRewind -Data <dir> -Install  # its game, with the disc files
 adb push MarioKart.iso /sdcard/Download/                                               # then Select disc image in the launcher
 ```
 
@@ -446,6 +460,14 @@ What has been verified on the development machine (September 2026):
   byte-identical to one the same toolchain built from a shell, and against the PC-built library it
   has the same soname, `NEEDED` list, 785 undefined symbols and 29,995 translated functions
   (61,974 defined against 61,975: the PC's older clang keeps one inline helper out of line).
+- **Device, 2026-09-17: Retro Rewind from its own kit.** The Retro Rewind APK carries a kit and no
+  game (66 MB). Its game built from that kit on the PC in 2.9 minutes (166 generated sources:
+  72 base shards, 24 profile-sensitive, 48 mod shards, the mod's data patches, 17 registration
+  shards and the 3 disc-generated sources), linked to a 157.6 MB `libmain.so` with the same import
+  list as the base one, 67,872 defined symbols against the base library's 61,975, and 5,905 symbols
+  the base library does not have. Packaged with the disc files (2.55 GB), imported on the Quest 3 in
+  under two minutes, and the mod runs: its own title screen, "Press the A Button", and the licence
+  menu, with the pack read from `retro_rewind_root`.
 
 Bring-up fixes that only a device could reveal:
 
@@ -556,7 +578,10 @@ or `EndAccess` errors); a black mirror too points at Aurora itself.
 - **Input.** D-pad (trick inputs) is not bound; remap in `Config.toml` or bind
   the thumbstick directions in a follow-up. Haptics are wired but nothing calls
   them yet.
-- **Retro Rewind on device** needs the mod's translation and its extracted
-  content pushed next to `DATA`, exactly like the desktop product.
+- **Retro Rewind on the headset** runs from a kit-built library (below), but its game must be built
+  on a PC and its pack copied next to `DATA` by hand. `adb push` cannot create directories inside
+  an app's external files directory (`secure_mkdirs failed`), so push the pack to `Download` and
+  copy it over on the device, then `chmod -R a+rX` it. The launcher does not fetch or update the
+  pack, and cannot build the mod on the headset.
 - **Release signing and store packaging** are out of scope; `Build-Quest.ps1`
   produces debug-signed APKs for sideloading.

runtime/cmake/PublicProducts.cmake

@@ -415,6 +415,14 @@ if(MKW_HAVE_RETRO_REWIND)
     if(MKW_RETRO_BLOB_OBJECTS)
         target_sources(RetroRewind PRIVATE ${MKW_RETRO_BLOB_OBJECTS})
     endif()
+    if(MKW_PLATFORM_ANDROID)
+        # Retro Rewind's game kit, the same idea as the base probe above: RetroRewind without any
+        # translated code, so the APK carries neither the game nor the mod.
+        add_library(mkw_quest_kit_probe_retro SHARED "${MKW_RETRO_REWIND_PRODUCT_SOURCE}")
+        mkw_configure_product(mkw_quest_kit_probe_retro WITHOUT_GAME)
+        target_precompile_headers(mkw_quest_kit_probe_retro REUSE_FROM WiiCompiled)
+        target_link_options(mkw_quest_kit_probe_retro PRIVATE "-Wl,--unresolved-symbols=ignore-all")
+    endif()
     add_custom_target(mkw_release DEPENDS WiiCompiled RetroRewind)
 else()
     add_custom_target(mkw_release DEPENDS WiiCompiled)
@@ -440,7 +448,7 @@ endif()
 
 set(MKW_ALL_BUILD_TARGETS
     mkw_runtime_common mkw_base_shared mkw_base_sensitive mkw_retro_sensitive
-    mkw_retro_rewind_functions WiiCompiled RetroRewind mkw_quest_kit_probe)
+    mkw_retro_rewind_functions WiiCompiled RetroRewind mkw_quest_kit_probe mkw_quest_kit_probe_retro)
 foreach(target IN LISTS MKW_ALL_BUILD_TARGETS)
     if(TARGET ${target} AND MKW_BASELINE_ARCH_FLAG)
         target_compile_options(${target} PRIVATE ${MKW_BASELINE_ARCH_FLAG})