Introducing Unreal Engine 4 for Archviz
In the architecture visualization world we always seek to achieve a result close to reality to provide our customers the feeling of seeing the finished project. But generally we are limited to still images and videos of these environments. What if we could enter the rooms, open the doors, walk on it, turn on and off lights, change the decor and still maintain photorealism?
Example of a interior walkthrough:
Example of exterior navigation:
That’s where Unreal Engine 4 enters. UE4 was recently launched in March 2014 by Epic Games as a powerful tool for creating games. However, it is an application that can be very effective for architectural visualization. It still has some graphic limitations compared to conventional renders as V-Ray and Corona, but that does not prevent you from getting incredibly realistic results in real time.
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Kitchen visualization in Unreal Engine 4
The Blueprint system for interactive archviz
In addition to the powerful graphics render, UE4 has a visual scripting system (called Blueprints) where you can create multiple interactions without writing a line of code. With the Blueprints system, you can perform actions such as lighting on/off switch, open and close doors, change object’s color and material, replace models in real time, change the time of the day, create defined camera tours and much more: the limit is your imagination. It is also possible to work with particles to create extremely realistic effects like fire, smoke and water. Resuming: it’s a games creation software that can work perfectly for architecture and allows you to give life to your project with the possibility to navigate and interact with it in real time; and you can still do all this with a graphic quality comparabled with other 3D renders.
Indirect Lighting in UE4
Indirect lighting is another strong point of UE4. The engine has an improved lighting system where you can reach a similar workflow to V-Ray using a skylight to simulate the lighting coming from the sky and a directional light to simulate the sun. Sometimes it is also recommended to use spotlights (which work in a similar way of V-Ray light planes) at some points to get better lighting.
What do I need to start?
- First of all you need a good computer to run UE4 software. The recommended hardware by Epic Games is a Quad-Core processor 2.5Ghz or faster, 8GB of RAM and at least a GeForce GTX470 or AMD Radeon 6870HD Series, but we do recommend a better setup if you are planning to really work with UE4.
- The second thing you need is an Unreal Engine 4 subscription. You can sign up and find more details on their website. The workflow to create an architectural project inside UE4 is based on modeling and texturing assets in a 3D software (3dsMax, May or other), import in UE4 and then set the scene. So, you will need a prepared model or a 3D software to create your model.
With this setup you are ready to start. Other applications may be needed for your project and i will talk about them later.
Preparing the assets in 3dsMax.
I will use 3dsMax to start my project, first modeling the static objects of architecture: floor, wal'ls, ceiling, etc. It is important to rename each object as they will be exported separately.
Texturing in 3ds Max
After modeling you should start the texturing process. All assets that will be prepared for UE4 should have open meshes and no overlapping faces. Then an extra UV channel should be created. The reason for this extra UV channel is because UE4 will use channel 1 as diffuse object texturing and channel 2 to bake the lightning map. If the faces are overlapping the lightmap will cause artifacts and will fail. In 3dsMax we can use the flatten-mapping method to open the mesh in primitive objects. This method works very well and is fast for this case. For more complex objects such as furniture, you should use other methods such as pelt mapping.
Exporting 3dsMax models to Unreal Engine 4
After you set the static objects, i recommend to export each object with their proper names. To export the models to Unreal Engine 4 you should use the FBX format.
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Setting up materials in Unreal Engine 4
When the materials window is opened, you will use similar concepts to conventional renders to represent the desired materials. You should use the Nodes concept, which will link parameters as Textures, Texture coordinates, normal maps, etc.
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When importing a texture to UE4, we can drag it into the materials window and connect to the Diffuse parameter. We will do this for parameters such as specular, reflection and normal. I will not go further into the creation of realistic materials within UE4, but you can see good examples in our complete projects. Also there will be a video course about these in the near future.
To create normal maps into your textures I recommend using a Photoshop plugin from
nVidia "NormalMapFilter".
Setting up the Lighting in Unreal Engine 4
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To begin this part, I recommend start testing the lighting only with part of the static architecture (walls, floor and ceiling): this way the lighting test time is reduced and when we insert the furniture, the lighting will be very polished.
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First insert a Skylight and start testing the intensity value. I suggest not to exaggerate this value to more than 2.
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To test the basic lighting click in Build > Lighting quality > High. Spotlight settings on the right.
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In this demo scene i configured my Lightmass (engine used to calculate GI in UE4) with the above parameters.
After many tests we came to these values to get free illumination spots (splotches or flickers). But remember that each scene should have a particularity.
Post-Process
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After figuring out the lighting and reaching the desirable effect, you will add a post-process volume where you will have more control on the visual of the scene. In this step you will be able to add Bloom and Vignette effects, control the Exhibition, Depth-of-field, color correction and more.
You can check everything in our complete projects and keep reading the Unreal documentation to experiment different settings. Thanks for reading! This tutorial was brought to you by UE4Arch:
http://ue4arch.com.