merge: asset-deletion line into master (16 spec suites, 169 cases)

The anonymisation pass replaced a pack name with a phrase containing
spaces, and the scanner splits package paths on whitespace, so the
expectation became /Game/a. Uses a single-token folder name instead.

Co-Authored-By: Claude Code <noreply@anthropic.com>

README.md

@@ -245,12 +245,58 @@ BOM обязателен: без него Excel ломает кириллицу.
 
 ---
 
+## Удаление отмеченных ассетов
+
+Кнопка **Delete ticked assets…** внизу панели, рядом с выгрузкой. Работает по тому же набору галочек.
+
+Удаление — единственная операция инструмента, которая уничтожает работу безвозвратно, поэтому проходит **через два окна**.
+
+### Окно 1 — наше
+
+Показывает весь отмеченный набор построчно: имя, тип, путь, **сколько ассетов снаружи набора ещё ссылается** на строку (в тултипе — их имена), и статус.
+
+- Ссылающиеся ассеты, которые сами удаляются вместе с целью, **в счётчик не попадают**. Иначе удаление блюпринта вместе с его единственным мешем выглядело бы опасным, хотя оно чистое.
+- Референсеры запрашиваются тем же `NoRequirements`-запросом, что и аудит: hard-only потерял бы каждую soft-ссылку, а soft-ссылка ломается точно так же — просто в рантайме, а не при загрузке.
+- Файл, помеченный **read-only на диске**, отмечается заранее. Под VCS, которая держит невытянутые файлы нередактируемыми, без этой пометки удаление падало бы по одному файлу в середине пачки.
+- Кнопка удаления неактивна, пока не поставлена галочка «I understand these files will be removed from the project».
+
+### Окно 2 — родное от UE
+
+После подтверждения набор уходит в `ObjectTools::DeleteAssets(..., bShowConfirmation=true)`, и открывается **штатное окно Delete Assets** движка — со списком ссылок, `Force Delete` и `Replace References`.
+
+Оно не имитировано, а вызвано: своя реализация замены ссылок означала бы свою реализацию `FAssetDeleteModel`, ошибки которой всплыли бы на чужом проекте.
+
+### Что удалять запрещено
+
+Отказы показываются в списке с причиной, строку нельзя отметить — молча выкинуть её из набора было бы хуже, чем отказать вслух.
+
+| Отказ | Почему |
+|---|---|
+| **Уровень** (`.umap`) | Уровень — это единица, относительно которой инструмент меряет использование. Удалив его, обесцениваешь каждую другую строку результата. Плюс движок сам отказывается удалять открытую карту, и итог зависел бы от того, какая карта сейчас загружена |
+| **OFPA-пакет** (`__ExternalActors__`, `__ExternalObjects__`) | Это не ассет, а размещённый на карте актор. Удалять его мимо level-редактора — значит править карту за его спиной, без его undo |
+| **`/Engine`, `/Script`, `/Temp`** | Не контент этого проекта |
+| **Уже отсутствует** | В реестре нет ассета под этим именем — удалять нечего |
+
+### ⚠️ Набор для удаления не расширяется зависимостями
+
+В отличие от выгрузки. Выгрузка тянет зависимости, чтобы меш приехал с материалами; удаление, расширенное так же, снесло бы контент, который никто не отмечал, — одна общая текстура утащила бы половину проекта.
+
+Удаляется ровно отмеченное и никогда больше.
+
+### ⚠️ После удаления результат помечается устаревшим
+
+Удалённые строки убираются из таблицы, но всё, что на них ссылалось, сохраняет прежние счётчики ссылок, а ассет, бывший `UsedByAssetsOnly` через удалённый блюпринт, теперь имеет другой вердикт. Панель говорит об этом прямо и просит перезапустить аудит, а не выдаёт старые числа за свежий замер.
+
+И главное — то же, что и везде в этом инструменте: **`Unreferenced` не означает «не используется»**. Реестр не видит путей, собранных строками, содержимого DataTable и событий FMOD. Окно удаления повторяет это предупреждение прямо в тексте.
+
+---
+
 ## Архитектура
 
 ```
 AssetUsageAuditCore    UncookedOnly  — весь анализ, ноль UI
 AssetUsageAuditEditor  Editor        — Slate-панель, настройки, команды
-AssetUsageAuditTests   UncookedOnly  — 15 spec-сьютов, 159 кейсов
+AssetUsageAuditTests   UncookedOnly  — 16 spec-сьютов, 169 кейсов
 ```
 
 **Инвариант Core:** не линковать `UnrealEd`, `AssetTools`, `ToolMenus`, `Slate`, `SlateCore`, `EditorSubsystem`. `AssetTools` editor-only транзитивно через `UnrealEd`.
@@ -340,7 +386,7 @@ WP_Example → BP_GameMode → PDA_MenuConfig → L_Other → …
   -unattended -nopause -nosplash -stdout -abslog="<abs path>"
 ```
 
-**159 кейсов в 15 spec-сьютах**, префикс `AssetUsageAudit.*`.
+**169 кейсов в 16 spec-сьютах**, префикс `AssetUsageAudit.*`.
 
 Три набора работают на **настоящем контенте проекта**, а не на выдуманных именах: `ExporterLive` (копирование, коллизии, раскрытие OFPA), `ExchangeExport` (конвертация) и `GraphFidelity` (сверка графа с реестром). Субъект они ищут через Asset Registry и берут **самый маленький** OFPA-уровень — на `WP_Example` тест копировал бы гигабайты. Если контент не найден, тест пишет предупреждение и не падает, поэтому в логе стоит смотреть на предупреждения: их отсутствие означает, что тесты реально работали с контентом.
 

Source/AssetUsageAuditCore/Private/AssetDeletionScan.cpp

@@ -0,0 +1,243 @@
+// MagentaDolphin 2026. Asset Usage Audit.
+
+#include "AssetDeletionScan.h"
+
+#include "AssetRegistry/IAssetRegistry.h"
+#include "AssetUsageAuditTypes.h"
+#include "AssetUsagePaths.h"
+#include "Engine/World.h"
+#include "HAL/FileManager.h"
+#include "Misc/PackageName.h"
+
+#define LOCTEXT_NAMESPACE "AssetDeletionScan"
+
+namespace AssetDeletionScan
+{
+    const TCHAR* LexToString(ERefusal Refusal)
+    {
+        switch (Refusal)
+        {
+        case ERefusal::None:              return TEXT("None");
+        case ERefusal::IsLevel:           return TEXT("IsLevel");
+        case ERefusal::IsExternalPackage: return TEXT("IsExternalPackage");
+        case ERefusal::NotProjectContent: return TEXT("NotProjectContent");
+        case ERefusal::Missing:           return TEXT("Missing");
+        }
+
+        return TEXT("Unknown");
+    }
+
+    FText DescribeRefusal(ERefusal Refusal)
+    {
+        switch (Refusal)
+        {
+        case ERefusal::None:
+            return FText::GetEmpty();
+
+        case ERefusal::IsLevel:
+            return LOCTEXT("RefusalLevel",
+                "Levels are never deleted by this tool. Delete a map from the Content Browser if you really mean to.");
+
+        case ERefusal::IsExternalPackage:
+            return LOCTEXT("RefusalExternal",
+                "This is a single actor stored outside its map (One File Per Actor). Delete it in the level editor, where it can be undone.");
+
+        case ERefusal::NotProjectContent:
+            return LOCTEXT("RefusalNotProject",
+                "Engine or plugin content - not part of this project.");
+
+        case ERefusal::Missing:
+            return LOCTEXT("RefusalMissing",
+                "No asset found under this package name; nothing to delete.");
+        }
+
+        return FText::GetEmpty();
+    }
+
+    FString FStats::Summarise() const
+    {
+        return FString::Printf(
+            TEXT("%d ticked: %d deletable, %d refused (levels %d, external actors %d, engine %d, missing %d); ")
+            TEXT("%d still referenced from outside the set, %d read-only on disk."),
+            Requested,
+            Deletable,
+            Requested - Deletable,
+            RefusedLevels,
+            RefusedExternal,
+            RefusedNotProjectContent,
+            RefusedMissing,
+            WithOutsideReferencers,
+            ReadOnly);
+    }
+
+    TArray<FCandidate> Scan(
+        IAssetRegistry& Registry,
+        const TArray<FName>& Packages,
+        const FOptions& Options,
+        FStats& OutStats)
+    {
+        OutStats = FStats();
+
+        TArray<FCandidate> Candidates;
+        Candidates.Reserve(Packages.Num());
+
+        // Membership is needed while classifying referencers, so it is built first and in full.
+        // Deleting A and B where B is A's only referencer must not report A as still in use.
+        TSet<FName> DeleteSet(Packages);
+
+        // Answering "is this a map" costs a registry query that allocates; the same package shows up
+        // as a referencer of many candidates, so the answer is cached across the whole scan.
+        TMap<FName, bool> LevelCache;
+
+        const auto IsLevelPackage = [&Registry, &LevelCache](FName PackageName) -> bool
+        {
+            if (const bool* Cached = LevelCache.Find(PackageName))
+            {
+                return *Cached;
+            }
+
+            TArray<FAssetData> Assets;
+            Registry.GetAssetsByPackageName(PackageName, Assets, /*bIncludeOnlyOnDiskAssets=*/true);
+
+            bool bIsLevel = false;
+            for (const FAssetData& AssetData : Assets)
+            {
+                if (AssetData.AssetClassPath == UWorld::StaticClass()->GetClassPathName())
+                {
+                    bIsLevel = true;
+                    break;
+                }
+            }
+
+            LevelCache.Add(PackageName, bIsLevel);
+            return bIsLevel;
+        };
+
+        TArray<FName> Referencers;
+        TArray<FAssetData> Assets;
+
+        for (FName PackageName : Packages)
+        {
+            if (PackageName.IsNone())
+            {
+                continue;
+            }
+
+            ++OutStats.Requested;
+
+            FCandidate Candidate;
+            Candidate.PackageName = PackageName;
+
+            const FString PackageString = PackageName.ToString();
+
+            // Filled from the path before any refusal, so a refused row still shows a name and a
+            // path. A row that says only "refused" with an empty name is not an explanation.
+            Candidate.AssetName = FName(*FPackageName::GetShortName(PackageString));
+            Candidate.PathFromProjectRoot = AssetUsagePaths::ToProjectRelativePath(PackageName, /*bIsLevel=*/false);
+
+            // Path-shaped refusals come first: they need no registry lookup, and two of them
+            // (script and engine content) would not produce a sensible FAssetData anyway.
+            if (AssetUsagePaths::IsScriptPackage(PackageName) || AssetUsagePaths::IsEngineOrTempPackage(PackageString))
+            {
+                Candidate.Refusal = ERefusal::NotProjectContent;
+                ++OutStats.RefusedNotProjectContent;
+                Candidates.Add(MoveTemp(Candidate));
+                continue;
+            }
+
+            if (AssetUsagePaths::IsExternalPackage(PackageName))
+            {
+                Candidate.Refusal = ERefusal::IsExternalPackage;
+                ++OutStats.RefusedExternal;
+                Candidates.Add(MoveTemp(Candidate));
+                continue;
+            }
+
+            Assets.Reset();
+            Registry.GetAssetsByPackageName(PackageName, Assets, /*bIncludeOnlyOnDiskAssets=*/true);
+
+            if (Assets.Num() == 0)
+            {
+                Candidate.Refusal = ERefusal::Missing;
+                ++OutStats.RefusedMissing;
+                Candidates.Add(MoveTemp(Candidate));
+                continue;
+            }
+
+            // The package's own asset, preferring the one the package is named after. A package
+            // usually holds exactly one, but the first entry is not guaranteed to be the UAsset.
+            const FAssetData* Primary = Assets.FindByPredicate([](const FAssetData& Data) { return Data.IsUAsset(); });
+            const FAssetData& AssetData = Primary ? *Primary : Assets[0];
+
+            Candidate.AssetName = AssetData.AssetName;
+            Candidate.ClassPath = AssetData.AssetClassPath;
+
+            const bool bIsLevel = AssetData.AssetClassPath == UWorld::StaticClass()->GetClassPathName();
+            LevelCache.Add(PackageName, bIsLevel);
+
+            Candidate.PathFromProjectRoot = AssetUsagePaths::ToProjectRelativePath(PackageName, bIsLevel);
+
+            if (bIsLevel)
+            {
+                Candidate.Refusal = ERefusal::IsLevel;
+                ++OutStats.RefusedLevels;
+                Candidates.Add(MoveTemp(Candidate));
+                continue;
+            }
+
+            // From here the candidate is deletable, and the remaining work is describing the
+            // consequences rather than deciding them.
+            Referencers.Reset();
+            Registry.GetReferencers(
+                PackageName, Referencers,
+                AssetUsageAudit::MakeTraversalCategory(), AssetUsageAudit::MakeTraversalQuery());
+
+            for (FName Referencer : Referencers)
+            {
+                if (Referencer == PackageName || DeleteSet.Contains(Referencer))
+                {
+                    continue;
+                }
+
+                ++Candidate.OutsideReferencerCount;
+
+                // An OFPA package is counted as a level reference without a registry lookup: it
+                // exists only to hold an actor placed in some map, so a reference from one means
+                // the asset is in a level right now.
+                if (AssetUsagePaths::IsExternalPackage(Referencer) || IsLevelPackage(Referencer))
+                {
+                    ++Candidate.LevelReferencerCount;
+                }
+
+                if (Candidate.OutsideReferencers.Num() < Options.MaxReferencersListed)
+                {
+                    Candidate.OutsideReferencers.Add(Referencer);
+                }
+            }
+
+            FString Filename;
+            if (FPackageName::DoesPackageExist(PackageString, &Filename))
+            {
+                Candidate.bReadOnlyOnDisk = IFileManager::Get().IsReadOnly(*Filename);
+            }
+
+            ++OutStats.Deletable;
+
+            if (Candidate.OutsideReferencerCount > 0)
+            {
+                ++OutStats.WithOutsideReferencers;
+            }
+
+            if (Candidate.bReadOnlyOnDisk)
+            {
+                ++OutStats.ReadOnly;
+            }
+
+            Candidates.Add(MoveTemp(Candidate));
+        }
+
+        return Candidates;
+    }
+}
+
+#undef LOCTEXT_NAMESPACE

Source/AssetUsageAuditCore/Public/AssetDeletionScan.h

@@ -0,0 +1,151 @@
+// MagentaDolphin 2026. Asset Usage Audit.
+
+#pragma once
+
+#include "CoreMinimal.h"
+#include "UObject/TopLevelAssetPath.h"
+
+class IAssetRegistry;
+
+/**
+ * What would happen if this set of packages were deleted - worked out before anything is touched.
+ *
+ * Deletion is the one operation in this tool that destroys work, and the audit's own verdicts are
+ * not a safe basis for it on their own: Unknown means "the registry cannot see it", not "unused",
+ * and the whole point of the five-state verdict is that the tool never presents a guess as a fact.
+ * So the scan answers a narrower, checkable question - who still points at this, right now, in the
+ * registry - and leaves the judgement to the person reading it.
+ *
+ * Pure registry and filesystem work. It loads nothing, deletes nothing, and is deliberately
+ * separate from the code that performs the delete: the analysis has to be testable without an
+ * editor, and the actual removal is ObjectTools' job in the Editor module, not ours.
+ */
+namespace AssetDeletionScan
+{
+    /**
+     * Why a ticked package will not be deleted.
+     *
+     * Refusals are policy, not failures, and each one is shown with its reason. Silently dropping a
+     * row from the delete set would be worse than refusing loudly - the user ticked it and is owed
+     * an explanation.
+     */
+    enum class ERefusal : uint8
+    {
+        /** No objection. */
+        None,
+
+        /**
+         * The package is a map.
+         *
+         * Refused by decision, not by capability. A level is the unit the whole tool measures usage
+         * against, and deleting one silently invalidates every other row in the result. The engine
+         * also refuses to delete a level that is currently open, which would make the outcome depend
+         * on which map the user happens to have loaded.
+         */
+        IsLevel,
+
+        /**
+         * A One File Per Actor package - an actor or object belonging to some level.
+         *
+         * Deleting one is not deleting an asset, it is deleting a placed actor out of a map behind
+         * the level editor's back. That belongs in the level editor, with its undo.
+         */
+        IsExternalPackage,
+
+        /** /Engine, /Script or /Temp. Not this project's to delete. */
+        NotProjectContent,
+
+        /** The registry has no asset under this package name; nothing to delete. */
+        Missing
+    };
+
+    ASSETUSAGEAUDITCORE_API const TCHAR* LexToString(ERefusal Refusal);
+
+    /** One line of explanation, suitable for showing beside the row. */
+    ASSETUSAGEAUDITCORE_API FText DescribeRefusal(ERefusal Refusal);
+
+    /** One ticked package and what stands in the way of deleting it. */
+    struct FCandidate
+    {
+        FName PackageName;
+        FName AssetName;
+        FTopLevelAssetPath ClassPath;
+
+        /** Content/... form, as the report shows it. */
+        FString PathFromProjectRoot;
+
+        ERefusal Refusal = ERefusal::None;
+
+        /**
+         * Packages that reference this one and are NOT themselves being deleted.
+         *
+         * The exclusion matters: deleting a Blueprint together with the mesh only it uses is a
+         * clean operation, and listing the Blueprint as a blocker would make every sensible
+         * multi-asset delete look dangerous. Truncated to FOptions::MaxReferencersListed - the list
+         * is there to be read, and forty names is not read.
+         */
+        TArray<FName> OutsideReferencers;
+
+        /** Full count before truncation. */
+        int32 OutsideReferencerCount = 0;
+
+        /** How many of those referencers are maps or OFPA packages - i.e. it is placed in a level. */
+        int32 LevelReferencerCount = 0;
+
+        /**
+         * The file exists on disk and is marked read-only.
+         *
+         * Worth surfacing here rather than discovering it as a failure afterwards: this project is
+         * Perforce-primary and unopened files are read-only by default, so a delete attempted
+         * without checking out first fails per-file, halfway through.
+         */
+        bool bReadOnlyOnDisk = false;
+
+        bool CanDelete() const
+        {
+            return Refusal == ERefusal::None;
+        }
+    };
+
+    struct FOptions
+    {
+        /** How many referencer names to keep per candidate. The count is always exact. */
+        int32 MaxReferencersListed = 8;
+    };
+
+    // Exported: Summarise is defined out of line, so the Editor module cannot link without this.
+    struct ASSETUSAGEAUDITCORE_API FStats
+    {
+        int32 Requested = 0;
+        int32 Deletable = 0;
+
+        int32 RefusedLevels = 0;
+        int32 RefusedExternal = 0;
+        int32 RefusedNotProjectContent = 0;
+        int32 RefusedMissing = 0;
+
+        /** Deletable candidates that something outside the set still points at. */
+        int32 WithOutsideReferencers = 0;
+
+        /** Deletable candidates whose file is read-only on disk. */
+        int32 ReadOnly = 0;
+
+        FString Summarise() const;
+    };
+
+    /**
+     * Classify the packages and collect their outside referencers.
+     *
+     * Order is preserved, refusals included, so the caller can show the whole ticked set with a
+     * reason against each row instead of a shorter list that quietly lost entries.
+     *
+     * Referencers are queried with AssetUsageAudit::MakeTraversalQuery() for the same reason the
+     * audit uses it: a Hard-only query misses every soft reference, and a soft reference still
+     * breaks when its target disappears - it just breaks at runtime instead of at load.
+     */
+    ASSETUSAGEAUDITCORE_API TArray<FCandidate> Scan(
+        IAssetRegistry& Registry,
+        const TArray<FName>& Packages,
+        const FOptions& Options,
+        FStats& OutStats);
+}

Source/AssetUsageAuditEditor/Private/SAssetDeleteDialog.cpp

@@ -0,0 +1,669 @@
+// MagentaDolphin 2026. Asset Usage Audit.
+
+#include "SAssetDeleteDialog.h"
+
+#include "AssetDeletionScan.h"
+#include "AssetRegistry/AssetRegistryModule.h"
+#include "AssetRegistry/IAssetRegistry.h"
+#include "AssetUsageAuditEditorModule.h"
+#include "Framework/Application/SlateApplication.h"
+#include "Framework/Docking/TabManager.h"
+#include "ObjectTools.h"
+#include "Styling/AppStyle.h"
+#include "Styling/CoreStyle.h"
+#include "Widgets/Input/SButton.h"
+#include "Widgets/Input/SCheckBox.h"
+#include "Widgets/Layout/SBorder.h"
+#include "Widgets/Layout/SBox.h"
+#include "Widgets/Layout/SSeparator.h"
+#include "Widgets/SBoxPanel.h"
+#include "Widgets/SWindow.h"
+#include "Widgets/Text/STextBlock.h"
+#include "Widgets/Views/SHeaderRow.h"
+#include "Widgets/Views/SListView.h"
+
+#define LOCTEXT_NAMESPACE "AssetDeleteDialog"
+
+namespace DeleteColumns
+{
+    static const FName Check(TEXT("Check"));
+    static const FName Name(TEXT("Name"));
+    static const FName Type(TEXT("Type"));
+    static const FName Path(TEXT("Path"));
+    static const FName Referencers(TEXT("Referencers"));
+    static const FName Status(TEXT("Status"));
+}
+
+namespace
+{
+    /** Red enough to read as a warning, light enough to stay legible on the dark editor theme. */
+    const FLinearColor DangerColor(0.95f, 0.35f, 0.30f);
+    const FLinearColor CautionColor(0.95f, 0.72f, 0.25f);
+    const FLinearColor MutedColor(0.6f, 0.6f, 0.6f);
+}
+
+/** One candidate plus its tick state. */
+struct FDeleteRow
+{
+    AssetDeletionScan::FCandidate Candidate;
+
+    /**
+     * Ticked by default when nothing objects.
+     *
+     * The user already ticked these rows in the panel; re-ticking them here would be busywork.
+     * What the window adds is the chance to *un*tick, having now been shown the referencers.
+     */
+    bool bChecked = false;
+};
+
+using FDeleteRowPtr = TSharedPtr<FDeleteRow>;
+
+class SDeleteRowWidget : public SMultiColumnTableRow<FDeleteRowPtr>
+{
+public:
+    SLATE_BEGIN_ARGS(SDeleteRowWidget) {}
+        SLATE_ARGUMENT(FDeleteRowPtr, Row)
+        SLATE_EVENT(FSimpleDelegate, OnCheckChanged)
+    SLATE_END_ARGS()
+
+    void Construct(const FArguments& InArgs, const TSharedRef<STableViewBase>& InOwnerTable)
+    {
+        Row = InArgs._Row;
+        OnCheckChanged = InArgs._OnCheckChanged;
+
+        SMultiColumnTableRow<FDeleteRowPtr>::Construct(FSuperRowType::FArguments(), InOwnerTable);
+    }
+
+    virtual TSharedRef<SWidget> GenerateWidgetForColumn(const FName& ColumnName) override
+    {
+        if (!Row.IsValid())
+        {
+            return SNullWidget::NullWidget;
+        }
+
+        const AssetDeletionScan::FCandidate& Candidate = Row->Candidate;
+        const bool bCanDelete = Candidate.CanDelete();
+
+        if (ColumnName == DeleteColumns::Check)
+        {
+            return SNew(SBox)
+                .HAlign(HAlign_Center)
+                .VAlign(VAlign_Center)
+                [
+                    SNew(SCheckBox)
+                    .IsEnabled(bCanDelete)
+                    .IsChecked_Lambda([this]()
+                    {
+                        return Row->bChecked ? ECheckBoxState::Checked : ECheckBoxState::Unchecked;
+                    })
+                    .OnCheckStateChanged_Lambda([this](ECheckBoxState NewState)
+                    {
+                        Row->bChecked = (NewState == ECheckBoxState::Checked);
+                        OnCheckChanged.ExecuteIfBound();
+                    })
+                ];
+        }
+
+        if (ColumnName == DeleteColumns::Name)
+        {
+            return SNew(STextBlock)
+                .Text(FText::FromName(Candidate.AssetName))
+                .ColorAndOpacity(bCanDelete ? FSlateColor::UseForeground() : FSlateColor(MutedColor))
+                .ToolTipText(FText::FromName(Candidate.PackageName));
+        }
+
+        if (ColumnName == DeleteColumns::Type)
+        {
+            return SNew(STextBlock)
+                .Text(FText::FromString(Candidate.ClassPath.GetAssetName().ToString()))
+                .ColorAndOpacity(FSlateColor(MutedColor));
+        }
+
+        if (ColumnName == DeleteColumns::Path)
+        {
+            return SNew(STextBlock)
+                .Text(FText::FromString(Candidate.PathFromProjectRoot))
+                .ColorAndOpacity(FSlateColor(MutedColor))
+                .ToolTipText(FText::FromString(Candidate.PathFromProjectRoot));
+        }
+
+        if (ColumnName == DeleteColumns::Referencers)
+        {
+            if (Candidate.OutsideReferencerCount == 0)
+            {
+                return SNew(STextBlock)
+                    .Text(LOCTEXT("NoReferencers", "none"))
+                    .ColorAndOpacity(FSlateColor(MutedColor))
+                    .ToolTipText(LOCTEXT("NoReferencersTip", "Nothing outside this delete set points at it, as far as the Asset Registry can see. Config files, C++ string paths and FMOD events are outside what it can see."));
+            }
+
+            // The names matter more than the number: "3" tells you to stop, the names tell you
+            // whether stopping was right.
+            FString Tooltip;
+            for (FName Referencer : Candidate.OutsideReferencers)
+            {
+                Tooltip += Referencer.ToString() + TEXT("\n");
+            }
+
+            if (Candidate.OutsideReferencerCount > Candidate.OutsideReferencers.Num())
+            {
+                Tooltip += FString::Printf(TEXT("... and %d more"),
+                    Candidate.OutsideReferencerCount - Candidate.OutsideReferencers.Num());
+            }
+
+            const FText Label = Candidate.LevelReferencerCount > 0
+                ? FText::Format(
+                    LOCTEXT("ReferencersWithLevels", "{0}  ({1} on levels)"),
+                    FText::AsNumber(Candidate.OutsideReferencerCount),
+                    FText::AsNumber(Candidate.LevelReferencerCount))
+                : FText::AsNumber(Candidate.OutsideReferencerCount);
+
+            return SNew(STextBlock)
+                .Text(Label)
+                .ColorAndOpacity(FSlateColor(CautionColor))
+                .ToolTipText(FText::FromString(Tooltip));
+        }
+
+        if (ColumnName == DeleteColumns::Status)
+        {
+            if (!bCanDelete)
+            {
+                return SNew(STextBlock)
+                    .Text(AssetDeletionScan::DescribeRefusal(Candidate.Refusal))
+                    .ColorAndOpacity(FSlateColor(MutedColor));
+            }
+
+            if (Candidate.bReadOnlyOnDisk)
+            {
+                return SNew(STextBlock)
+                    .Text(LOCTEXT("ReadOnly", "read-only on disk"))
+                    .ColorAndOpacity(FSlateColor(CautionColor))
+                    .ToolTipText(LOCTEXT("ReadOnlyTip", "The file is not writable. Perforce-primary projects keep unopened files read-only, so an unopened file is read-only and the delete will fail on it. Check it out first."));
+            }
+
+            return SNew(STextBlock)
+                .Text(LOCTEXT("WillDelete", "will be deleted"))
+                .ColorAndOpacity(FSlateColor(DangerColor));
+        }
+
+        return SNullWidget::NullWidget;
+    }
+
+private:
+    FDeleteRowPtr Row;
+    FSimpleDelegate OnCheckChanged;
+};
+
+/**
+ * The window body.
+ *
+ * Owns the scan result and the tick state; deletes nothing until Delete is pressed, and reports
+ * back through the outcome struct rather than mutating anything the panel owns.
+ */
+class SAssetDeleteDialog : public SCompoundWidget
+{
+public:
+    SLATE_BEGIN_ARGS(SAssetDeleteDialog) {}
+        SLATE_ARGUMENT(TArray<FName>, Packages)
+        SLATE_ARGUMENT(TSharedPtr<SWindow>, ParentWindow)
+    SLATE_END_ARGS()
+
+    void Construct(const FArguments& InArgs)
+    {
+        ParentWindow = InArgs._ParentWindow;
+
+        FAssetRegistryModule& RegistryModule =
+            FModuleManager::LoadModuleChecked<FAssetRegistryModule>(TEXT("AssetRegistry"));
+        IAssetRegistry& Registry = RegistryModule.Get();
+
+        AssetDeletionScan::FOptions ScanOptions;
+
+        const TArray<AssetDeletionScan::FCandidate> Candidates =
+            AssetDeletionScan::Scan(Registry, InArgs._Packages, ScanOptions, Stats);
+
+        for (const AssetDeletionScan::FCandidate& Candidate : Candidates)
+        {
+            FDeleteRowPtr NewRow = MakeShared<FDeleteRow>();
+            NewRow->Candidate = Candidate;
+            NewRow->bChecked = Candidate.CanDelete();
+            Rows.Add(NewRow);
+        }
+
+        UE_LOG(LogAssetUsageAuditEditor, Log, TEXT("Delete scan: %s"), *Stats.Summarise());
+
+        BuildHeaderRow();
+
+        ChildSlot
+        [
+            SNew(SBorder)
+            .BorderImage(FAppStyle::GetBrush("ToolPanel.GroupBorder"))
+            .Padding(12.0f)
+            [
+                SNew(SVerticalBox)
+
+                // --- The headline ------------------------------------------------------------
+                //
+                // Stated as a consequence rather than as a question. "Delete 12 assets?" invites a
+                // reflex click; naming what disappears does not.
+                + SVerticalBox::Slot()
+                .AutoHeight()
+                .Padding(0.0f, 0.0f, 0.0f, 6.0f)
+                [
+                    SNew(STextBlock)
+                    .Font(FCoreStyle::GetDefaultFontStyle("Bold", 13))
+                    .ColorAndOpacity(FSlateColor(DangerColor))
+                    .Text(FText::Format(
+                        LOCTEXT("Headline", "{0} asset file(s) will be deleted from this project."),
+                        FText::AsNumber(Stats.Deletable)))
+                ]
+
+                + SVerticalBox::Slot()
+                .AutoHeight()
+                .Padding(0.0f, 0.0f, 0.0f, 8.0f)
+                [
+                    SNew(STextBlock)
+                    .AutoWrapText(true)
+                    .Text(LOCTEXT("Explanation",
+                        "This removes the files from disk. It is not an export and there is no undo - what protects you is source control, so make sure this content is submitted or checked out before continuing.\n\n"
+                        "Bear in mind what the audit cannot see: assets named from C++ or Blueprint strings, rows inside DataTables, and FMOD events are invisible to the Asset Registry. An asset with no referencers here is not proof that nothing uses it."))
+                ]
+
+                // --- Reference warning -------------------------------------------------------
+                + SVerticalBox::Slot()
+                .AutoHeight()
+                .Padding(0.0f, 0.0f, 0.0f, 8.0f)
+                [
+                    SNew(SBorder)
+                    .BorderImage(FAppStyle::GetBrush("ToolPanel.DarkGroupBorder"))
+                    .Padding(8.0f)
+                    .Visibility_Lambda([this]()
+                    {
+                        return Stats.WithOutsideReferencers > 0 ? EVisibility::Visible : EVisibility::Collapsed;
+                    })
+                    [
+                        SNew(STextBlock)
+                        .AutoWrapText(true)
+                        .ColorAndOpacity(FSlateColor(CautionColor))
+                        .Text(FText::Format(
+                            LOCTEXT("ReferencerWarning",
+                                "{0} of them are still referenced by something outside this selection. Deleting those leaves the referencing assets pointing at nothing.\n"
+                                "Unreal's own Delete Assets window opens next and lists every reference, where you can replace them with another asset or force the delete."),
+                            FText::AsNumber(Stats.WithOutsideReferencers)))
+                    ]
+                ]
+
+                // --- Refusals ----------------------------------------------------------------
+                //
+                // Shown, not hidden. The user ticked those rows; a delete that quietly acts on
+                // fewer assets than were ticked is how trust in a tool is lost.
+                + SVerticalBox::Slot()
+                .AutoHeight()
+                .Padding(0.0f, 0.0f, 0.0f, 8.0f)
+                [
+                    SNew(STextBlock)
+                    .AutoWrapText(true)
+                    .ColorAndOpacity(FSlateColor(MutedColor))
+                    .Visibility_Lambda([this]()
+                    {
+                        return (Stats.Requested - Stats.Deletable) > 0 ? EVisibility::Visible : EVisibility::Collapsed;
+                    })
+                    .Text_Lambda([this]() { return GetRefusalText(); })
+                ]
+
+                + SVerticalBox::Slot()
+                .FillHeight(1.0f)
+                [
+                    SNew(SBox)
+                    .MinDesiredHeight(240.0f)
+                    [
+                        SAssignNew(ListView, SListView<FDeleteRowPtr>)
+                        .ListItemsSource(&Rows)
+                        .SelectionMode(ESelectionMode::None)
+                        .HeaderRow(HeaderRow)
+                        .OnGenerateRow_Lambda([this](FDeleteRowPtr Item, const TSharedRef<STableViewBase>& OwnerTable)
+                        {
+                            return SNew(SDeleteRowWidget, OwnerTable)
+                                .Row(Item)
+                                .OnCheckChanged(FSimpleDelegate::CreateLambda([this]() { Invalidate(EInvalidateWidgetReason::Paint); }));
+                        })
+                    ]
+                ]
+
+                + SVerticalBox::Slot()
+                .AutoHeight()
+                .Padding(0.0f, 8.0f)
+                [
+                    SNew(SSeparator)
+                ]
+
+                // --- Acknowledgement ---------------------------------------------------------
+                //
+                // A deliberate second action. The Delete button stays disabled until this is
+                // ticked, which costs one click and removes the "I meant to press Cancel" class
+                // of accident entirely.
+                + SVerticalBox::Slot()
+                .AutoHeight()
+                .Padding(0.0f, 0.0f, 0.0f, 8.0f)
+                [
+                    SNew(SCheckBox)
+                    .IsChecked_Lambda([this]() { return bAcknowledged ? ECheckBoxState::Checked : ECheckBoxState::Unchecked; })
+                    .OnCheckStateChanged_Lambda([this](ECheckBoxState NewState) { bAcknowledged = (NewState == ECheckBoxState::Checked); })
+                    [
+                        SNew(STextBlock)
+                        .Margin(FMargin(4.0f, 0.0f, 0.0f, 0.0f))
+                        .Text(LOCTEXT("Acknowledge", "I understand these files will be removed from the project."))
+                    ]
+                ]
+
+                + SVerticalBox::Slot()
+                .AutoHeight()
+                [
+                    SNew(SHorizontalBox)
+
+                    + SHorizontalBox::Slot()
+                    .VAlign(VAlign_Center)
+                    [
+                        SNew(STextBlock)
+                        .ColorAndOpacity(FSlateColor(MutedColor))
+                        .Text_Lambda([this]()
+                        {
+                            return FText::Format(
+                                LOCTEXT("Footer", "{0} ticked of {1} that can be deleted."),
+                                FText::AsNumber(CountChecked()),
+                                FText::AsNumber(Stats.Deletable));
+                        })
+                    ]
+
+                    + SHorizontalBox::Slot()
+                    .AutoWidth()
+                    .Padding(4.0f, 0.0f)
+                    [
+                        SNew(SButton)
+                        .Text(LOCTEXT("Cancel", "Cancel"))
+                        .OnClicked(this, &SAssetDeleteDialog::OnCancel)
+                    ]
+
+                    + SHorizontalBox::Slot()
+                    .AutoWidth()
+                    .Padding(4.0f, 0.0f)
+                    [
+                        SNew(SButton)
+                        .Text_Lambda([this]()
+                        {
+                            return FText::Format(
+                                LOCTEXT("DeleteButton", "Delete {0} asset(s)"),
+                                FText::AsNumber(CountChecked()));
+                        })
+                        .ToolTipText(LOCTEXT("DeleteButtonTip", "Hand the ticked assets to Unreal's delete, which will show its own reference window before anything is removed."))
+                        .IsEnabled_Lambda([this]() { return bAcknowledged && CountChecked() > 0; })
+                        .OnClicked(this, &SAssetDeleteDialog::OnDelete)
+                    ]
+                ]
+            ]
+        ];
+    }
+
+    bool WasAccepted() const
+    {
+        return bAccepted;
+    }
+
+    /** Packages the user confirmed, in the order they were listed. */
+    TArray<FName> GetConfirmedPackages() const
+    {
+        TArray<FName> Result;
+
+        for (const FDeleteRowPtr& Row : Rows)
+        {
+            if (Row->bChecked && Row->Candidate.CanDelete())
+            {
+                Result.Add(Row->Candidate.PackageName);
+            }
+        }
+
+        return Result;
+    }
+
+    const AssetDeletionScan::FStats& GetStats() const
+    {
+        return Stats;
+    }
+
+private:
+    void BuildHeaderRow()
+    {
+        HeaderRow = SNew(SHeaderRow)
+
+            + SHeaderRow::Column(DeleteColumns::Check)
+              .DefaultLabel(FText::GetEmpty())
+              .FixedWidth(28.0f)
+              [
+                  SNew(SBox)
+                  .HAlign(HAlign_Center)
+                  .VAlign(VAlign_Center)
+                  [
+                      SNew(SCheckBox)
+                      .IsChecked_Lambda([this]() { return GetHeaderCheckState(); })
+                      .OnCheckStateChanged_Lambda([this](ECheckBoxState NewState) { SetAllChecked(NewState == ECheckBoxState::Checked); })
+                  ]
+              ]
+
+            + SHeaderRow::Column(DeleteColumns::Name)
+              .DefaultLabel(LOCTEXT("ColName", "Asset"))
+              .FillWidth(0.24f)
+
+            + SHeaderRow::Column(DeleteColumns::Type)
+              .DefaultLabel(LOCTEXT("ColType", "Type"))
+              .FillWidth(0.13f)
+
+            + SHeaderRow::Column(DeleteColumns::Path)
+              .DefaultLabel(LOCTEXT("ColPath", "Path"))
+              .FillWidth(0.33f)
+
+            + SHeaderRow::Column(DeleteColumns::Referencers)
+              .DefaultLabel(LOCTEXT("ColReferencers", "Referenced by"))
+              .FillWidth(0.15f)
+
+            + SHeaderRow::Column(DeleteColumns::Status)
+              .DefaultLabel(LOCTEXT("ColStatus", "Status"))
+              .FillWidth(0.15f);
+    }
+
+    ECheckBoxState GetHeaderCheckState() const
+    {
+        const int32 Checked = CountChecked();
+
+        if (Checked == 0)
+        {
+            return ECheckBoxState::Unchecked;
+        }
+
+        return Checked == Stats.Deletable ? ECheckBoxState::Checked : ECheckBoxState::Undetermined;
+    }
+
+    void SetAllChecked(bool bNewChecked)
+    {
+        for (const FDeleteRowPtr& Row : Rows)
+        {
+            if (Row->Candidate.CanDelete())
+            {
+                Row->bChecked = bNewChecked;
+            }
+        }
+
+        if (ListView.IsValid())
+        {
+            ListView->RequestListRefresh();
+        }
+    }
+
+    int32 CountChecked() const
+    {
+        int32 Count = 0;
+
+        for (const FDeleteRowPtr& Row : Rows)
+        {
+            if (Row->bChecked && Row->Candidate.CanDelete())
+            {
+                ++Count;
+            }
+        }
+
+        return Count;
+    }
+
+    FText GetRefusalText() const
+    {
+        TArray<FString> Parts;
+
+        if (Stats.RefusedLevels > 0)
+        {
+            Parts.Add(FString::Printf(TEXT("%d level(s)"), Stats.RefusedLevels));
+        }
+
+        if (Stats.RefusedExternal > 0)
+        {
+            Parts.Add(FString::Printf(TEXT("%d actor package(s)"), Stats.RefusedExternal));
+        }
+
+        if (Stats.RefusedNotProjectContent > 0)
+        {
+            Parts.Add(FString::Printf(TEXT("%d outside project content"), Stats.RefusedNotProjectContent));
+        }
+
+        if (Stats.RefusedMissing > 0)
+        {
+            Parts.Add(FString::Printf(TEXT("%d already gone"), Stats.RefusedMissing));
+        }
+
+        return FText::Format(
+            LOCTEXT("RefusalSummary", "Kept out of the delete: {0}. They are listed below with a reason, and cannot be ticked."),
+            FText::FromString(FString::Join(Parts, TEXT(", "))));
+    }
+
+    FReply OnDelete()
+    {
+        bAccepted = true;
+        CloseWindow();
+        return FReply::Handled();
+    }
+
+    FReply OnCancel()
+    {
+        bAccepted = false;
+        CloseWindow();
+        return FReply::Handled();
+    }
+
+    void CloseWindow()
+    {
+        if (ParentWindow.IsValid())
+        {
+            ParentWindow->RequestDestroyWindow();
+        }
+    }
+
+    TArray<FDeleteRowPtr> Rows;
+    AssetDeletionScan::FStats Stats;
+
+    bool bAcknowledged = false;
+    bool bAccepted = false;
+
+    TSharedPtr<SWindow> ParentWindow;
+    TSharedPtr<SListView<FDeleteRowPtr>> ListView;
+    TSharedPtr<SHeaderRow> HeaderRow;
+};
+
+FAssetDeleteOutcome ShowAssetDeleteDialog(const TArray<FName>& Packages)
+{
+    FAssetDeleteOutcome Outcome;
+    Outcome.Requested = Packages.Num();
+
+    FAssetRegistryModule& RegistryModule =
+        FModuleManager::LoadModuleChecked<FAssetRegistryModule>(TEXT("AssetRegistry"));
+    IAssetRegistry& Registry = RegistryModule.Get();
+
+    // The engine refuses to delete while the registry is still discovering, and does so with a
+    // transient notification that is easy to miss. Better to wait here than to have the delete
+    // quietly do nothing.
+    if (Registry.IsLoadingAssets())
+    {
+        Registry.WaitForCompletion();
+    }
+
+    TSharedRef<SWindow> Window = SNew(SWindow)
+        .Title(LOCTEXT("WindowTitle", "Delete ticked assets"))
+        .ClientSize(FVector2D(940.0f, 620.0f))
+        .SupportsMinimize(false)
+        .SupportsMaximize(false);
+
+    TSharedRef<SAssetDeleteDialog> Dialog = SNew(SAssetDeleteDialog)
+        .Packages(Packages)
+        .ParentWindow(Window);
+
+    Window->SetContent(Dialog);
+
+    FSlateApplication::Get().AddModalWindow(Window, FGlobalTabmanager::Get()->GetRootWindow());
+
+    Outcome.Refused = Dialog->GetStats().Requested - Dialog->GetStats().Deletable;
+
+    if (!Dialog->WasAccepted())
+    {
+        UE_LOG(LogAssetUsageAuditEditor, Log, TEXT("Delete cancelled; nothing was touched."));
+        return Outcome;
+    }
+
+    const TArray<FName> Confirmed = Dialog->GetConfirmedPackages();
+    Outcome.bCancelled = false;
+    Outcome.Attempted = Confirmed.Num();
+
+    if (Confirmed.Num() == 0)
+    {
+        return Outcome;
+    }
+
+    // Resolve to FAssetData at the last moment. The scan ran before the window opened and the
+    // user may have spent a while reading it; a stale FAssetData would ask the engine to delete
+    // something that has already moved.
+    TArray<FAssetData> ToDelete;
+
+    for (FName Package : Confirmed)
+    {
+        TArray<FAssetData> Assets;
+        Registry.GetAssetsByPackageName(Package, Assets, /*bIncludeOnlyOnDiskAssets=*/true);
+        ToDelete.Append(Assets);
+    }
+
+    if (ToDelete.Num() == 0)
+    {
+        UE_LOG(LogAssetUsageAuditEditor, Warning,
+            TEXT("Nothing was deleted: none of the %d confirmed packages still hold an asset."), Confirmed.Num());
+        return Outcome;
+    }
+
+    // The engine's own delete, with its confirmation left on. That window is where referencers are
+    // listed and where Force Delete and Replace References live - the behaviour the request asked
+    // to match, obtained by using it rather than by imitating it.
+    const int32 ObjectsDeleted = ObjectTools::DeleteAssets(ToDelete, /*bShowConfirmation=*/true);
+
+    // Count packages, not objects: the engine returns deleted UObjects, and asking the registry
+    // what actually disappeared is the only figure that matches the Content Browser.
+    for (FName Package : Confirmed)
+    {
+        TArray<FAssetData> Remaining;
+        Registry.GetAssetsByPackageName(Package, Remaining, /*bIncludeOnlyOnDiskAssets=*/true);
+
+        if (Remaining.Num() == 0)
+        {
+            Outcome.DeletedPackages.Add(Package);
+        }
+    }
+
+    UE_LOG(LogAssetUsageAuditEditor, Display,
+        TEXT("Delete finished: %d package(s) gone of %d confirmed (%d object(s) reported by the engine)."),
+        Outcome.DeletedPackages.Num(), Confirmed.Num(), ObjectsDeleted);
+
+    return Outcome;
+}
+
+#undef LOCTEXT_NAMESPACE

Source/AssetUsageAuditEditor/Private/SAssetDeleteDialog.h

@@ -0,0 +1,46 @@
+// MagentaDolphin 2026. Asset Usage Audit.
+
+#pragma once
+
+#include "CoreMinimal.h"
+
+/** What the delete window ended up doing. Everything the panel needs to report afterwards. */
+struct FAssetDeleteOutcome
+{
+    /** Packages handed to the window. */
+    int32 Requested = 0;
+
+    /** Refused by policy - levels, OFPA packages, engine content. Never reaches the engine. */
+    int32 Refused = 0;
+
+    /** Ticked and passed to ObjectTools. */
+    int32 Attempted = 0;
+
+    /**
+     * Packages the registry can no longer find afterwards.
+     *
+     * Measured rather than taken from the engine's return value: ObjectTools reports a count of
+     * deleted *objects*, and one package can hold several. Asking the registry what is actually
+     * gone is the only figure that matches what the user will see in the Content Browser.
+     */
+    TArray<FName> DeletedPackages;
+
+    /** True when the user closed or cancelled the window; nothing was touched. */
+    bool bCancelled = true;
+};
+
+/**
+ * Show the delete window: what is about to be destroyed, what still points at it, and why some
+ * rows are refused.
+ *
+ * Modal, and deliberately heavier than the export window. Export is reversible by deleting the
+ * output folder; this is not, and the window's job is to be read rather than clicked through -
+ * hence the per-row referencer count, the explicit acknowledgement, and Cancel as the default.
+ *
+ * The window does not delete anything itself. Once confirmed it hands the assets to
+ * ObjectTools::DeleteAssets with the engine's own confirmation enabled, so the familiar Delete
+ * Assets dialog - referencer list, Force Delete, Replace References - appears exactly as it does
+ * from the Content Browser. Reimplementing that would mean reimplementing reference replacement,
+ * and getting it subtly wrong on someone's project.
+ */
+FAssetDeleteOutcome ShowAssetDeleteDialog(const TArray<FName>& Packages);

Source/AssetUsageAuditEditor/Private/SAssetUsageAuditPanel.cpp

@@ -12,6 +12,7 @@
 #include "AssetUsageExporter.h"
 #include "AssetUsagePaths.h"
 #include "AssetUsageReportWriter.h"
+#include "SAssetDeleteDialog.h"
 #include "AssetRegistry/AssetRegistryModule.h"
 #include "AssetRegistry/IAssetRegistry.h"
 #include "Algo/AllOf.h"
@@ -580,6 +581,33 @@ void SAssetUsageAuditPanel::Construct(const FArguments& InArgs)
                 .OnClicked(this, &SAssetUsageAuditPanel::OnExportFilesClicked)
                 .IsEnabled(this, &SAssetUsageAuditPanel::HasCheckedAssets)
             ]
+
+            // Delete sits last and behind a separator, deliberately. It acts on the same ticked
+            // set as Export, so it belongs on this bar, but it is the only irreversible action in
+            // the tool and must never be the button someone reaches by muscle memory.
+            + SHorizontalBox::Slot()
+            .AutoWidth()
+            .VAlign(VAlign_Center)
+            .Padding(8.0f, 2.0f, 2.0f, 2.0f)
+            [
+                SNew(SSeparator)
+                .Orientation(Orient_Vertical)
+            ]
+
+            + SHorizontalBox::Slot()
+            .AutoWidth()
+            .VAlign(VAlign_Center)
+            .Padding(2.0f, 0.0f)
+            [
+                SNew(SButton)
+                .Text(LOCTEXT("DeleteTicked", "Delete ticked assets..."))
+                .ToolTipText(LOCTEXT("DeleteTickedTip",
+                    "Permanently delete the ticked assets from the project. Levels are never deleted. "
+                    "Shows what still references them before anything is removed."))
+                .ButtonColorAndOpacity(FLinearColor(0.55f, 0.16f, 0.16f))
+                .OnClicked(this, &SAssetUsageAuditPanel::OnDeleteClicked)
+                .IsEnabled(this, &SAssetUsageAuditPanel::HasCheckedAssets)
+            ]
         ]
     ];
 }
@@ -2224,6 +2252,83 @@ FReply SAssetUsageAuditPanel::OnExportFilesClicked()
     return FReply::Handled();
 }
 
+// --- Deleting ----------------------------------------------------------------------------------
+
+FReply SAssetUsageAuditPanel::OnDeleteClicked()
+{
+    TArray<FAssetUsageRow> Rows;
+    GetCheckedRows(Rows);
+
+    if (Rows.IsEmpty())
+    {
+        return FReply::Handled();
+    }
+
+    TArray<FName> Packages;
+    Packages.Reserve(Rows.Num());
+
+    for (const FAssetUsageRow& Row : Rows)
+    {
+        Packages.Add(Row.PackageName);
+    }
+
+    // Deliberately NOT widened with the dependency closure, unlike export. Export widens so that a
+    // mesh arrives with its materials; widening a delete the same way would destroy content nobody
+    // ticked, and a single shared texture would drag half the project along with it. Delete acts on
+    // exactly what was ticked, and never on more.
+    const FAssetDeleteOutcome Outcome = ShowAssetDeleteDialog(Packages);
+
+    if (Outcome.bCancelled)
+    {
+        StatusText = LOCTEXT("DeleteCancelled", "Delete cancelled - nothing was changed.");
+        return FReply::Handled();
+    }
+
+    ForgetDeletedPackages(Outcome.DeletedPackages);
+
+    StatusText = FText::Format(
+        LOCTEXT("DeleteFinished",
+            "Deleted {0} of {1} ticked asset(s); {2} were refused. Reference counts elsewhere in this result are now out of date - run the audit again."),
+        FText::AsNumber(Outcome.DeletedPackages.Num()),
+        FText::AsNumber(Outcome.Requested),
+        FText::AsNumber(Outcome.Refused));
+
+    return FReply::Handled();
+}
+
+void SAssetUsageAuditPanel::ForgetDeletedPackages(const TArray<FName>& DeletedPackages)
+{
+    if (DeletedPackages.IsEmpty())
+    {
+        return;
+    }
+
+    const TSet<FName> Gone(DeletedPackages);
+
+    LastResult.Rows.RemoveAll([&Gone](const FAssetUsageRow& Row)
+    {
+        return Gone.Contains(Row.PackageName);
+    });
+
+    AllRows.RemoveAll([&Gone](const FAssetUsageRowPtr& Row)
+    {
+        return Row.IsValid() && Gone.Contains(Row->PackageName);
+    });
+
+    for (FName Package : DeletedPackages)
+    {
+        CheckedPackages.Remove(Package);
+    }
+
+    // Removing the rows is honest but incomplete: everything that referenced them still carries the
+    // reference counts it had before, and an asset that was UsedByAssetsOnly through a now-deleted
+    // Blueprint has a different verdict than the one on screen. Marking the result stale says so,
+    // rather than leaving figures that look freshly measured.
+    bResultStale = true;
+
+    RebuildFilteredRows();
+}
+
 void SAssetUsageAuditPanel::RunMigrateExport(const TArray<FAssetUsageRow>& Rows, const FAssetExportRequest& Request)
 {
     TArray<FName> Packages;

Source/AssetUsageAuditEditor/Private/SAssetUsageAuditPanel.h

@@ -278,6 +278,31 @@ private:
     FReply OnExportFilesClicked();
     bool HasCheckedAssets() const;
 
+    // --- Deleting ----------------------------------------------------------------------------
+
+    /**
+     * Delete the ticked assets, after two confirmations.
+     *
+     * Sits beside Export because it acts on the same ticked set, and is the reason the audit is
+     * worth running: the point of finding unused content is to be able to remove it. It is kept
+     * visually apart and never becomes the default action.
+     *
+     * Levels are refused outright - see AssetDeletionScan::ERefusal::IsLevel. Everything else the
+     * window explains before anything is touched, and the destruction itself is ObjectTools' code,
+     * not ours.
+     */
+    FReply OnDeleteClicked();
+
+    /**
+     * Drop deleted packages from the result without re-running the sweep.
+     *
+     * A full re-run after a delete would cost minutes on this project, and the rows that remain are
+     * still correct - what changed is that some assets are gone, plus the referencer counts of
+     * whatever pointed at them. The result is marked stale so the numbers are not mistaken for a
+     * fresh sweep.
+     */
+    void ForgetDeletedPackages(const TArray<FName>& DeletedPackages);
+
     /** Byte copy of the package files, expanding levels to their OFPA packages. */
     void RunCopyExport(const TArray<FAssetUsageRow>& Rows, const FAssetExportRequest& Request);
 

Source/AssetUsageAuditTests/Private/AssetDeletionScan.spec.cpp

@@ -0,0 +1,449 @@
+// MagentaDolphin 2026. Asset Usage Audit.
+
+#include "AssetDeletionScan.h"
+
+#include "AssetRegistry/ARFilter.h"
+#include "AssetRegistry/IAssetRegistry.h"
+#include "AssetUsageAuditTypes.h"
+#include "AssetUsagePaths.h"
+#include "Engine/World.h"
+#include "HAL/FileManager.h"
+#include "Misc/AutomationTest.h"
+#include "Misc/PackageName.h"
+
+#if WITH_DEV_AUTOMATION_TESTS
+
+/**
+ * The refusals, and the referencer arithmetic behind the warning.
+ *
+ * This is the only part of the tool that leads to something being destroyed, so the tests are
+ * written against the two claims the delete window makes to the user: "these will not be touched",
+ * and "this many things still point at that". Both are decided here; the window only renders them.
+ *
+ * Nothing in this spec deletes anything. AssetDeletionScan cannot - it holds no delete code at all,
+ * which is exactly why the analysis was split out of the Editor module.
+ */
+BEGIN_DEFINE_SPEC(AssetDeletionScanSpec,
+    "AssetUsageAudit.DeletionScan",
+    EAutomationTestFlags::EditorContext | EAutomationTestFlags::EngineFilter)
+
+    static IAssetRegistry& ReadyRegistry()
+    {
+        IAssetRegistry& Registry = IAssetRegistry::GetChecked();
+        if (Registry.IsLoadingAssets())
+        {
+            Registry.WaitForCompletion();
+        }
+        return Registry;
+    }
+
+    /** First map in /Game, chosen deterministically so a failure is reproducible. */
+    static FName FindLevelPackage()
+    {
+        IAssetRegistry& Registry = ReadyRegistry();
+
+        FARFilter Filter;
+        Filter.PackagePaths.Add(FName(TEXT("/Game")));
+        Filter.bRecursivePaths = true;
+        Filter.bIncludeOnlyOnDiskAssets = true;
+        Filter.ClassPaths.Add(UWorld::StaticClass()->GetClassPathName());
+
+        TArray<FName> Levels;
+        Registry.EnumerateAssets(Filter, [&Levels](const FAssetData& AssetData)
+        {
+            Levels.Add(AssetData.PackageName);
+            return Levels.Num() < 512;
+        });
+
+        if (Levels.IsEmpty())
+        {
+            return NAME_None;
+        }
+
+        Levels.Sort(FNameLexicalLess());
+        return Levels[0];
+    }
+
+    /** First One File Per Actor package, if this project has any. */
+    static FName FindExternalPackage()
+    {
+        IAssetRegistry& Registry = ReadyRegistry();
+
+        FARFilter Filter;
+        Filter.PackagePaths.Add(FName(TEXT("/Game/__ExternalActors__")));
+        Filter.bRecursivePaths = true;
+        Filter.bIncludeOnlyOnDiskAssets = true;
+
+        TArray<FName> Found;
+        Registry.EnumerateAssets(Filter, [&Found](const FAssetData& AssetData)
+        {
+            Found.Add(AssetData.PackageName);
+            return false;
+        });
+
+        return Found.IsEmpty() ? NAME_None : Found[0];
+    }
+
+    /**
+     * An ordinary asset together with one package that references it.
+     *
+     * Both halves are needed to prove the delete-set exclusion: the referencer has to be a real one
+     * for "referenced from outside" and "referenced from inside the set" to be the same edge seen
+     * twice, which is the whole point of the check.
+     */
+    static FName FindReferencedAsset(FName& OutReferencer)
+    {
+        IAssetRegistry& Registry = ReadyRegistry();
+
+        FARFilter Filter;
+        Filter.PackagePaths.Add(FName(TEXT("/Game")));
+        Filter.bRecursivePaths = true;
+        Filter.bIncludeOnlyOnDiskAssets = true;
+
+        TArray<FName> Candidates;
+        Registry.EnumerateAssets(Filter, [&Candidates](const FAssetData& AssetData)
+        {
+            if (AssetData.IsRedirector() || AssetData.AssetClassPath == UWorld::StaticClass()->GetClassPathName())
+            {
+                return true;
+            }
+
+            if (AssetUsagePaths::IsExternalPackage(AssetData.PackageName))
+            {
+                return true;
+            }
+
+            Candidates.Add(AssetData.PackageName);
+            return Candidates.Num() < 4096;
+        });
+
+        Candidates.Sort(FNameLexicalLess());
+
+        TArray<FName> Referencers;
+
+        for (FName Candidate : Candidates)
+        {
+            Referencers.Reset();
+            Registry.GetReferencers(Candidate, Referencers,
+                AssetUsageAudit::MakeTraversalCategory(), AssetUsageAudit::MakeTraversalQuery());
+
+            for (FName Referencer : Referencers)
+            {
+                if (Referencer != Candidate)
+                {
+                    OutReferencer = Referencer;
+                    return Candidate;
+                }
+            }
+        }
+
+        return NAME_None;
+    }
+
+END_DEFINE_SPEC(AssetDeletionScanSpec)
+
+void AssetDeletionScanSpec::Define()
+{
+    Describe("Refusing what must not be deleted", [this]()
+    {
+        It("refuses a map", [this]()
+        {
+            const FName Level = FindLevelPackage();
+
+            if (Level.IsNone())
+            {
+                AddWarning(TEXT("This project has no maps; skipping."));
+                return;
+            }
+
+            AssetDeletionScan::FStats Stats;
+            const TArray<AssetDeletionScan::FCandidate> Candidates =
+                AssetDeletionScan::Scan(ReadyRegistry(), { Level }, AssetDeletionScan::FOptions(), Stats);
+
+            if (Candidates.Num() != 1)
+            {
+                AddError(TEXT("expected exactly one candidate"));
+                return;
+            }
+
+            // The user's rule, and the one refusal that is policy rather than capability: the engine
+            // would happily delete an unopened map.
+            TestEqual(TEXT("refused as a level"),
+                Candidates[0].Refusal, AssetDeletionScan::ERefusal::IsLevel);
+            TestFalse(TEXT("not deletable"), Candidates[0].CanDelete());
+            TestEqual(TEXT("counted as a refused level"), Stats.RefusedLevels, 1);
+            TestEqual(TEXT("nothing deletable"), Stats.Deletable, 0);
+        });
+
+        It("refuses a One File Per Actor package", [this]()
+        {
+            const FName External = FindExternalPackage();
+
+            if (External.IsNone())
+            {
+                AddWarning(TEXT("This project has no external actor packages; skipping."));
+                return;
+            }
+
+            AssetDeletionScan::FStats Stats;
+            const TArray<AssetDeletionScan::FCandidate> Candidates =
+                AssetDeletionScan::Scan(ReadyRegistry(), { External }, AssetDeletionScan::FOptions(), Stats);
+
+            if (Candidates.Num() != 1)
+            {
+                AddError(TEXT("expected exactly one candidate"));
+                return;
+            }
+
+            // Deleting one of these is removing a placed actor from a map behind the level editor's
+            // back - no undo, and the map keeps a reference to a package that no longer exists.
+            TestEqual(TEXT("refused as external"),
+                Candidates[0].Refusal, AssetDeletionScan::ERefusal::IsExternalPackage);
+            TestEqual(TEXT("counted"), Stats.RefusedExternal, 1);
+        });
+
+        It("refuses engine content", [this]()
+        {
+            AssetDeletionScan::FStats Stats;
+            const TArray<AssetDeletionScan::FCandidate> Candidates = AssetDeletionScan::Scan(
+                ReadyRegistry(),
+                { FName(TEXT("/Engine/BasicShapes/Cube")) },
+                AssetDeletionScan::FOptions(),
+                Stats);
+
+            if (Candidates.Num() != 1)
+            {
+                AddError(TEXT("expected exactly one candidate"));
+                return;
+            }
+
+            TestEqual(TEXT("refused as engine content"),
+                Candidates[0].Refusal, AssetDeletionScan::ERefusal::NotProjectContent);
+            TestEqual(TEXT("counted"), Stats.RefusedNotProjectContent, 1);
+        });
+
+        It("refuses a package the registry does not know", [this]()
+        {
+            AssetDeletionScan::FStats Stats;
+            const TArray<AssetDeletionScan::FCandidate> Candidates = AssetDeletionScan::Scan(
+                ReadyRegistry(),
+                { FName(TEXT("/Game/AssetUsageAuditNoSuchPackage")) },
+                AssetDeletionScan::FOptions(),
+                Stats);
+
+            if (Candidates.Num() != 1)
+            {
+                AddError(TEXT("expected exactly one candidate"));
+                return;
+            }
+
+            TestEqual(TEXT("reported as missing"),
+                Candidates[0].Refusal, AssetDeletionScan::ERefusal::Missing);
+            TestEqual(TEXT("counted"), Stats.RefusedMissing, 1);
+        });
+
+        It("keeps refused rows in the result rather than dropping them", [this]()
+        {
+            const FName Level = FindLevelPackage();
+
+            if (Level.IsNone())
+            {
+                AddWarning(TEXT("This project has no maps; skipping."));
+                return;
+            }
+
+            const FName Missing(TEXT("/Game/AssetUsageAuditNoSuchPackage"));
+            const FName Engine(TEXT("/Engine/BasicShapes/Cube"));
+
+            AssetDeletionScan::FStats Stats;
+            const TArray<AssetDeletionScan::FCandidate> Candidates = AssetDeletionScan::Scan(
+                ReadyRegistry(), { Level, Missing, Engine }, AssetDeletionScan::FOptions(), Stats);
+
+            // A refusal the user cannot see is indistinguishable from the tool losing their
+            // selection, so every ticked package must come back with a reason attached.
+            TestEqual(TEXT("all three returned"), Candidates.Num(), 3);
+            TestEqual(TEXT("in the original order"), Candidates[0].PackageName, Level);
+            TestEqual(TEXT("in the original order"), Candidates[1].PackageName, Missing);
+            TestEqual(TEXT("in the original order"), Candidates[2].PackageName, Engine);
+
+            TestEqual(TEXT("requested count matches"), Stats.Requested, 3);
+            TestEqual(TEXT("none deletable"), Stats.Deletable, 0);
+        });
+    });
+
+    Describe("Counting what still points at the asset", [this]()
+    {
+        It("lists a referencer that is not itself being deleted", [this]()
+        {
+            FName Referencer = NAME_None;
+            const FName Asset = FindReferencedAsset(Referencer);
+
+            if (Asset.IsNone())
+            {
+                AddWarning(TEXT("No referenced asset was found; skipping."));
+                return;
+            }
+
+            AssetDeletionScan::FStats Stats;
+            const TArray<AssetDeletionScan::FCandidate> Candidates =
+                AssetDeletionScan::Scan(ReadyRegistry(), { Asset }, AssetDeletionScan::FOptions(), Stats);
+
+            if (Candidates.Num() != 1 || !Candidates[0].CanDelete())
+            {
+                AddError(TEXT("expected one deletable candidate"));
+                return;
+            }
+
+            TestTrue(TEXT("at least one outside referencer"), Candidates[0].OutsideReferencerCount > 0);
+            TestTrue(TEXT("the known referencer is listed"),
+                Candidates[0].OutsideReferencers.Contains(Referencer)
+                || Candidates[0].OutsideReferencerCount > Candidates[0].OutsideReferencers.Num());
+            TestEqual(TEXT("counted in the stats"), Stats.WithOutsideReferencers, 1);
+        });
+
+        It("does not count a referencer that is in the delete set", [this]()
+        {
+            FName Referencer = NAME_None;
+            const FName Asset = FindReferencedAsset(Referencer);
+
+            if (Asset.IsNone() || Referencer.IsNone())
+            {
+                AddWarning(TEXT("No referenced asset was found; skipping."));
+                return;
+            }
+
+            AssetDeletionScan::FStats Before;
+            const TArray<AssetDeletionScan::FCandidate> Alone =
+                AssetDeletionScan::Scan(ReadyRegistry(), { Asset }, AssetDeletionScan::FOptions(), Before);
+
+            AssetDeletionScan::FStats After;
+            const TArray<AssetDeletionScan::FCandidate> Together =
+                AssetDeletionScan::Scan(ReadyRegistry(), { Asset, Referencer }, AssetDeletionScan::FOptions(), After);
+
+            const AssetDeletionScan::FCandidate* Widened =
+                Together.FindByPredicate([Asset](const AssetDeletionScan::FCandidate& C) { return C.PackageName == Asset; });
+
+            if (Alone.Num() != 1 || !Widened)
+            {
+                AddError(TEXT("expected the asset in both scans"));
+                return;
+            }
+
+            // Deleting a Blueprint together with the mesh only it uses is a clean operation. If the
+            // Blueprint were still counted, every sensible multi-asset delete would look dangerous
+            // and the warning would stop meaning anything.
+            TestTrue(TEXT("the count dropped once its referencer joined the set"),
+                Widened->OutsideReferencerCount < Alone[0].OutsideReferencerCount);
+
+            TestFalse(TEXT("the referencer is no longer listed"),
+                Widened->OutsideReferencers.Contains(Referencer));
+        });
+
+        It("truncates the listed names but not the count", [this]()
+        {
+            FName Referencer = NAME_None;
+            const FName Asset = FindReferencedAsset(Referencer);
+
+            if (Asset.IsNone())
+            {
+                AddWarning(TEXT("No referenced asset was found; skipping."));
+                return;
+            }
+
+            AssetDeletionScan::FOptions Options;
+            Options.MaxReferencersListed = 1;
+
+            AssetDeletionScan::FStats Stats;
+            const TArray<AssetDeletionScan::FCandidate> Candidates =
+                AssetDeletionScan::Scan(ReadyRegistry(), { Asset }, Options, Stats);
+
+            if (Candidates.Num() != 1)
+            {
+                AddError(TEXT("expected one candidate"));
+                return;
+            }
+
+            TestTrue(TEXT("at most one name kept"), Candidates[0].OutsideReferencers.Num() <= 1);
+            TestTrue(TEXT("the count is not truncated with it"),
+                Candidates[0].OutsideReferencerCount >= Candidates[0].OutsideReferencers.Num());
+        });
+    });
+
+    Describe("Describing a deletable asset", [this]()
+    {
+        It("reports the read-only flag the way the filesystem does", [this]()
+        {
+            FName Referencer = NAME_None;
+            const FName Asset = FindReferencedAsset(Referencer);
+
+            if (Asset.IsNone())
+            {
+                AddWarning(TEXT("No suitable asset was found; skipping."));
+                return;
+            }
+
+            AssetDeletionScan::FStats Stats;
+            const TArray<AssetDeletionScan::FCandidate> Candidates =
+                AssetDeletionScan::Scan(ReadyRegistry(), { Asset }, AssetDeletionScan::FOptions(), Stats);
+
+            if (Candidates.Num() != 1 || !Candidates[0].CanDelete())
+            {
+                AddError(TEXT("expected one deletable candidate"));
+                return;
+            }
+
+            FString Filename;
+            if (!FPackageName::DoesPackageExist(Asset.ToString(), &Filename))
+            {
+                AddError(TEXT("the package has no file on disk"));
+                return;
+            }
+
+            // Perforce-primary projects keep unopened files read-only, so read-only is the normal state of an unopened
+            // file. Reporting it up front is the difference between a warning and a delete that
+            // fails halfway through the selection.
+            TestEqual(TEXT("matches the filesystem"),
+                Candidates[0].bReadOnlyOnDisk, IFileManager::Get().IsReadOnly(*Filename));
+
+            TestEqual(TEXT("read-only count agrees"),
+                Stats.ReadOnly, Candidates[0].bReadOnlyOnDisk ? 1 : 0);
+
+            AddInfo(FString::Printf(TEXT("%s: %d outside referencer(s), %d from levels, read-only %s."),
+                *Asset.ToString(),
+                Candidates[0].OutsideReferencerCount,
+                Candidates[0].LevelReferencerCount,
+                Candidates[0].bReadOnlyOnDisk ? TEXT("yes") : TEXT("no")));
+        });
+
+        It("fills in the name, class and project-relative path", [this]()
+        {
+            FName Referencer = NAME_None;
+            const FName Asset = FindReferencedAsset(Referencer);
+
+            if (Asset.IsNone())
+            {
+                AddWarning(TEXT("No suitable asset was found; skipping."));
+                return;
+            }
+
+            AssetDeletionScan::FStats Stats;
+            const TArray<AssetDeletionScan::FCandidate> Candidates =
+                AssetDeletionScan::Scan(ReadyRegistry(), { Asset }, AssetDeletionScan::FOptions(), Stats);
+
+            if (Candidates.Num() != 1)
+            {
+                AddError(TEXT("expected one candidate"));
+                return;
+            }
+
+            // The window shows these three and nothing else per row, so an empty one is a blank
+            // line in front of someone about to press Delete.
+            TestFalse(TEXT("name filled"), Candidates[0].AssetName.IsNone());
+            TestTrue(TEXT("class filled"), Candidates[0].ClassPath.IsValid());
+            TestTrue(TEXT("path starts at Content/"),
+                Candidates[0].PathFromProjectRoot.StartsWith(TEXT("Content/")));
+        });
+    });
+}
+
+#endif // WITH_DEV_AUTOMATION_TESTS