[TUTORIAL] How to "Uncook" assets (with some limitations for the moment)

[akkk44]

Greetings, it seems that even though I commend the return false line in the source, the asset manager still refuse to open in 4.26. The script also gives me some errors. Is there a solution for 4.26?

[Richtoveen]

animations are not working right now this is the stack that crashes does anyone have any fix? https://imgur.com/a/csO0cTf

[Dreadfred]

Hello Vincent,

I should have linked the hair idle animation to 03 hair mesh, other characters might differ. If you want to make character playable or place in level/world you will need to setup a blueprint, here's a link to a good basic tutorial Its in ue5 but would work in 4.26 and above (Uses enhanced input) ]https://dev.epicgames.com/community/learning/courses/kry/build-a-third-person-character-from-scratch/mDv/build-a-third-person-character-from-scratch-introduction]
you should be able to put it all together using set master pose component (V4) or Copy pose from mesh (games like blade and soul).

[artifex0]

I was able to get this sort of working in UE 4.26.2.

In addition to the instructions in the video, I commented out the return false under if (Package->bIsCookedForEditor) in Engine\Source\Editor\UnrealEd\Private\Subsystems\AssetEditorSubsystem.cpp and compiled.

Since I don't really know C++, I didn't understand most of the code in the custom class- but I described the various errors I experienced to ChatGPT, and it produced the following modifications:

AssetDecooker.h:

Code:

// Youtube → Notorious R

#pragma once

#include "CoreMinimal.h"
#include "UObject/Object.h"
#include "UObject/NoExportTypes.h"
#include "Materials/Material.h"
#include "AssetDecooker.generated.h"

UCLASS()
class BLANKSANDBOX_API UAssetDecooker : public UObject
{
GENERATED_BODY()

public:
UFUNCTION(BlueprintCallable, Category = "Asset Tools", meta = (DisplayName = "Decook Assets"))
static void DecookAssets(TArray<UObject*> Objects);
};

AssetDecooker.cpp line 101:

Code:

if (lodData.SkinWeightVertexBuffer.GetNumVertices() > 0)
{
FSkinWeightInfo info = lodData.SkinWeightVertexBuffer.GetVertexSkinWeights(idx);
FMemory::Memcpy(vtx.InfluenceBones, info.InfluenceBones, sizeof(info.InfluenceBones));
FMemory::Memcpy(vtx.InfluenceWeights, info.InfluenceWeights, sizeof(info.InfluenceWeights));
}

AssetDecooker.cpp line 114:

Code:

if (range.Length > 0)
{
TArray<int32> indices2;
indices2.Reserve(range.Length);
for (uint32 l = 0; l < range.Length; ++l)
indices2.Add(renderSection.DuplicatedVerticesBuffer.DupVertData[range.Index + l]);

section.OverlappingVertices.Add(k, indices2);
}

AssetDecooker.cpp line 219:

Code:

if (UAnimSequence* typedAsset2 = Cast<UAnimSequence>(asset))
dstPackage = DecookAnimSequence(typedAsset2);
else if (USkeletalMesh* typedAsset3 = Cast<USkeletalMesh>(asset))
dstPackage = DecookSkeletalMesh(typedAsset3);
else if (UPhysicsAsset* typedAsset4 = Cast<UPhysicsAsset>(asset))
dstPackage = DecookPhysicsAsset(typedAsset4);

if (dstPackage != nullptr) {
FString packageName = dstPackage->GetName();
FString savePath = FPaths::ProjectContentDir() + packageName;
dstPackage->MarkPackageDirty();
UPackage::SavePackage(dstPackage, NULL, RF_Standalone, *savePath, GError, nullptr, false, true, SAVE_NoError);
savePackages.Add(dstPackage);
}

This code doesn't actually save the uncooked model in the correct directory, and you'll need to manually add the .uasset extension to the files it produces- probably easy fixes, but I'm dead tired of trying to get this to work, so I'll leave that for someone else to correct.  Note also that you'll need to replace "BLANKSANDBOX" in AssetDecooker.h with the name of your project.

I was able to successfully uncook a skeletalmesh with this code and export a .fbx.  This was a model with more than four skin weights per vertex, so neither umodel nor FModel were able to export it correctly (they discard the smallest weights when there are more than four, which led to serious clipping problems in this case). The model exported with this method, however, did have all of the correct skin weights.  Thanks, Soulax!

[Aoe]

So how can I uncook assets in 4.26.2 and same question for 5.3.2

https://dev.epicgames.com/community/snippets/QE0/unreal-engine-cooked-asset-uncooked-asset-editor-script

Pasted this but it is not working, are some values missing when you paste it or is it some setting they missed that I don't have active?

Actually followed the french guys video and managed to build the engine but in 4.26.2 the 4.22 attempt failed.

I am surprised it is so hard to find guides for this.

When I try to use uncook script action in unmodded engine i get: Assertion failed: Owner->IsMeshDescriptionValid(0) [File:D:/Build/++UE4/Sync/Engine/Source/Runtime/Engine/Private/StaticMesh.cpp] [Line: 2569] Bad MeshDescription on /Game/Inventory/B1