UE5 Decals with AI Textures

What You Will Build

• AI-generated decal textures with transparent backgrounds
• Clean imported decal textures inside a dedicated Unreal folder
• A reusable deferred decal base material
• Material instances for multiple decal variations
• Placed decals inside a level on walls, floors, ramps, and curved surfaces
• A scalable decal workflow you can reuse across projects

Why This Workflow Matters

A lot of beginners treat decals like random editor junk they drag into a scene at the end. That is the wrong mindset. Decals are part of environment storytelling and scene polish. They help explain what a place is, what happened there, and how worn or maintained it feels.

The problem is that many developers get blocked at the first step because they do not have ready-made decal textures or they assume they need full artistic skills to create them. That is where AI texture generation becomes useful. It gives you a practical shortcut, but only if you use it properly and bring the results into Unreal with a clean setup.

That is what this tutorial is about.

Step 1: Generate Decal Textures with AI

Before creating any material in Unreal Engine, you need the decal textures themselves. In this workflow, those textures are generated with an AI image tool instead of painted manually.

This is useful for things like:

• warning signs
• graffiti
• industrial symbols
• cracks
• damage marks
• number labels
• hazard indicators

The exact generator does not matter much. The important part is the output. The image needs to be clean, isolated, and usable as a decal.

In the tutorial, multiple decal textures are created this way so there is a small decal library ready for Unreal. The prompts can be reused directly or modified to fit the style of your own project.

Transparency Is the Most Important Part

If there is one thing you should not screw up here, it is transparency.

Every decal image should have a properly transparent background. That means no solid color background, no fake cutout, no ugly halo around the edges, and no leftover background bleed.

Yes, there are other workflows where people generate images on a solid green, white, or black background and then try to extract the shape later with masks. That can work. It is also more annoying, more error-prone, and less beginner-friendly.

A transparent PNG workflow is cleaner and faster. That is why it is used here.

Step 2: Import and Organize the Decal Textures in Unreal

Once your decal images are ready, open the Content Drawer in Unreal Engine and create a dedicated folder for them. A simple name like:

Decals

is enough.

Drag and drop all your decal images into that folder and import them into the project.

This part sounds trivial, but keeping decal content in a dedicated folder matters. Projects get messy fast when people dump textures randomly across the Content Drawer.

Step 3: Apply Paper 2D Texture Settings

After the textures are imported, select them all, right-click, and go to:

Sprite Actions > Apply Paper 2D Texture Settings

This step is important because it helps keep the decal texture edges cleaner and sharper, especially around transparent areas.

If you skip this, your imported decals can end up looking softer, dirtier, or more artifact-heavy than they should.

Save the textures after applying the settings.

Why Sharp Transparency Matters for Decals

A decal is often only as good as its edge quality. A warning symbol, graffiti mark, or crack with blurry transparency instantly looks cheap once projected onto a wall.

Clean alpha handling is one of those tiny technical details that users may never consciously notice, but they absolutely feel the difference when it is bad.

Step 4: Create the First Decal Material

Now that the textures are ready, choose one decal texture to start with. In the tutorial, a graffiti texture is used first.

Right-click the texture and choose:

Create Material

Unreal will automatically create a new material using that texture.

Open the material and click the main material node on the right side.

Step 5: Convert the Material into a Deferred Decal

In the material settings, change:

• Material Domain to Deferred Decal
• Blend Mode to Translucent

This tells Unreal that the material is meant to project onto existing surfaces as a decal instead of behaving like a normal surface material.

Then connect:

• RGB from the texture sample to Base Color
• Alpha from the texture sample to Opacity

That gives you a simple, effective decal setup.

There are more advanced and more production-heavy approaches, including masked setups, but this translucent approach is easier to follow and works well for this workflow.

Masked vs Translucent for Decals

You can also use a masked workflow in some cases by connecting alpha to Opacity Mask instead, but for a beginner-friendly reusable setup, translucent is simpler and less annoying to set up.

That is why it is used here. It keeps the material graph clean and easy to understand.

Step 6: Turn the Texture into a Parameter

Here is the smarter workflow.

Instead of creating a totally separate material for every decal texture, take the texture sample node and convert it into a parameter. Give it a simple name such as:

Texture

This turns your first decal material into a reusable base decal material.

That means the material structure stays the same, and only the assigned texture changes between decal variations.

Why Material Instances Are Better Than Separate Materials

This is where a lot of people waste time.

You could create one full material per decal texture. That works. It is also messy and scales badly.

A better workflow is:

• one base decal material
• multiple material instances using different textures

That keeps the project cleaner, easier to maintain, and easier to expand later. It is also the more sensible workflow if you ever want to swap textures through Blueprint or code later.

Step 7: Create Material Instances for Each Decal

Save the base decal material, then right-click it and choose:

Create Material Instance

Open the material instance and locate the texture parameter under the global parameter values.

Enable the parameter and assign one of your decal textures to it.

Save the material instance.

Repeat this process for the rest of your decal textures. By the end, you should have a base decal material and a list of decal instances that all use the same material logic but display different textures.

Step 8: Place a Decal Actor in the Level

Once the decal instances are ready, open your map.

At the top of the editor, use the quick add menu and search for:

Decal

Drag a Decal Actor into the level.

Move it close to the surface where you want the decal to be projected, such as a wall.

Step 9: Rotate the Decal Correctly

Decals project forward, which means rotation matters a lot.

Select the decal actor and rotate it using the rotate gizmo or the Details panel. In the tutorial, an example rotation like this is used:

X = 90
Y = 0
Z = -90

The exact values depend on the target surface. Walls, floors, ramps, and curved surfaces can all need slightly different adjustments.

This is why decals confuse beginners. They place one, it projects in the wrong direction, and they think the material is broken. Usually the material is fine. The rotation is wrong.

Step 10: Adjust Decal Size

In the Details panel, find:

Decal Size

and set dimensions that fit your texture and target surface. An example setup from the tutorial is:

60, 120, 120

You can also unlock the values and adjust each axis independently if needed.

Decal size has a huge effect on readability. Too small and the decal disappears. Too large and it looks ridiculous or stretched.

Step 11: Assign the Decal Material Instance

With the decal actor selected, go to the Details panel and assign one of your material instances to the:

Decal Material

slot.

At this point, the decal should project correctly onto the target surface.

This is your first fully working AI-generated decal inside the level.

Step 12: Test Decals on Different Surfaces

Do not stop after placing one decal on one wall.

Test them on:

• walls
• floors
• ramps
• curved surfaces
• angled geometry

This matters because decal projection behaves differently depending on the receiving surface and the projection angle.

The more you test placement manually, the faster you stop guessing and start understanding how decals really behave in Unreal.

How the Full Decal Workflow Works

The full process is straightforward:

1. Generate clean decal textures with transparent backgrounds
2. Import them into a dedicated Unreal folder
3. Apply Paper 2D texture settings
4. Create one reusable deferred decal base material
5. Turn the texture into a parameter
6. Create material instances for each decal texture
7. Place decal actors into the level
8. Adjust rotation, size, and material assignment until the projection looks correct

That gives you a reusable decal pipeline that is clean enough for real projects.

Common Mistakes to Avoid

• Using decal images without true transparency
• Importing textures without cleaning up their settings
• Creating separate full materials for every decal instead of using instances
• Forgetting to change the material domain to Deferred Decal
• Projecting decals with bad rotation and blaming the material
• Using oversized decals that look stretched or fake
• Never testing decals on different surface shapes

Where This Workflow Is Useful

This decal pipeline is useful for far more than graffiti.

You can use it for:

• hazard signs
• industrial labels
• wall cracks
• damage marks
• street art
• shatter patterns
• environment storytelling details
• UI-like world labels inside levels

Once the base material exists, expanding the library becomes easy.

Conclusion

In this tutorial, you built a complete Unreal Engine decal workflow using AI-generated textures, reusable decal materials, material instances, and manual decal placement inside a level. The result is a practical system that helps you create better-looking environments without needing to be a full-time texture artist.

More importantly, it gives you a reusable workflow instead of one-off hacky decal setups.

Watch the full tutorial on YouTube: Create High Quality Decals in Unreal Engine Using AI Textures

Subscribe for more Unreal Engine tutorials: Subscribe to Rambod on YouTube

Frequently Asked Questions

Can I create good decals in Unreal Engine without being an artist?

Yes. With clean AI-generated textures, proper transparency, and a good decal material workflow, you can build solid reusable decals without painting them by hand.

Why does the decal texture need a transparent background?

Because decal materials rely on clean alpha information. A bad background creates ugly edges, unwanted boxes, and poor blending on surfaces.

Why use one base decal material and material instances?

Because it is cleaner, more scalable, and easier to maintain than creating a separate full material for every single decal texture.

Why is my decal projecting in the wrong direction?

Usually because the decal actor rotation is wrong. Decals project forward, so orientation matters as much as the material itself.

What is the benefit of applying Paper 2D texture settings?

It helps keep imported decal textures sharper and cleaner, especially around transparent edges, which is useful for this kind of workflow.

Can I use this workflow for warning signs, graffiti, and cracks?

Yes. That is exactly the point. The same decal pipeline works for many decal types as long as the texture is clean and suited for projection.