Automotive Configurator Sample

The automotive industry is increasingly turning to real time solutions, such as Unreal Engine 4 (UE4), to drive their visualization and commercial projects. The Automotive Configurator sample is built using Epic Games’ best practices for the creation of a vehicle configurator, a common use case for 3d visualization artists in the automotive industry.

The Automotive Configurator sample demonstrates the use of the following features:

• Variant Manager
• Real-time Ray Tracing
• Volumetric Clouds
• Control Rig
• Sequencer
• Movie Render Queue

How To Use the Automotive Configurator

Downloading the Sample

The project sample is freely available via the Learn tab in the Unreal Engine section of the Epic Games Launcher. Other asset packs used in the making of the sample can be found for free in the Marketplace tab.

• Automotive Materials Pack
• Salt Flats Environment (Coming soon)

To setup a project with the Automotive Configurator sample, use the following steps:

1. Open the Epic Games Launcher and click on the Unreal Engine button on the sidebar. Then open the Learn tab.

   
2. Scroll down to the Engine Features Samples and select the Automotive Configurator sample. Click the Free button to add the sample to your Vault.
3. Click the Create Project button and follow the on screen instructions to download the sample and start a new project.
4. Open your new project in the Unreal Editor.
5. Open the Plugins menu by going to the Edit menu and selecting the Plugins option. Enable the Movie Render Queue, Color Correct Regions, Control Rig, and Variant Manager plugins, if necessary. This may require you to restart the Editor.

Navigating the User Interface

Built on the Product Configurator template and using the Variant Manager, the Automotive Configurator allows you to choose from a variety of saved Static Mesh configurations called Variants that can be used to customize an Audi A5.

The configurator is controlled via the interface buttons located at the bottom of the screen:

The Automotive Configurator also includes focus points, represented by blue flashing circles, that have been animated using Control Rig, UE4’s Blueprint-based animation control system:

• Open/Close Doors: Open and close the driver/passenger side doors.
• Open/Close Convertible Soft Top: Open and close the convertible top by clicking on the roof control switch located by the rearview mirror in any of the interior views.
• Open/Close Trunk: Open and close the trunk lid.
• Horn: You can honk the horn.
• Start/Stop the Engine: Clicking the Engine Start button will start or stop the engine. This will power up/down the dash gauges, Audi Virtual Cockpit and light up the front lights and tail lights.

Rendering the Commercial View

Clicking the Play button in the Configurator will transport your customized vehicle to the Commercial mode.

In Commercial mode, your vehicle becomes the star of your very own TV spot. This mode takes your vehicle through several camera shots often seen in car commercials. You can control the commercial using the following interface options:

Powered by Sequencer, the camera races across the salt flats, moving to highlight the wheels and interior. The car commercial takes advantage of Real-time Ray Tracing for lighting and shadows, and can be saved to your computer with the touch of a button thanks to the Movie Render Queue runtime feature.

Variant Manager

The Automotive Configurator is built on the Product Configurator template and uses the Variant Manager to store the various asset configurations used to customize your vehicle.

Move the slider to see the different Trim variants

Each configuration option is stored in an entry called a Variant. Each variant points to a property on an Actor that is changed when the variant is activated. Variants are arranged into Variant Sets and the data is used by the BP_Configurator blueprint to populate the user interface with options. In the image above, we can see that when the Tango Red Metallic paint option is selected the Variant Manager applies that value to different static mesh components on the vehicle Actor.

For more information on using the Variant Manager, please see our Variant Manager documentation.

Real-time Ray Tracing

Ray tracing techniques offer the ability to create realistic 3d content that display natural looking lighting and shadows.

Real-time Ray Tracing uses a hybrid Ray Tracer that combines ray tracing with UE4’s existing raster techniques. It also uses a physically-based Path Tracer that works similar to many offline renderers. Together, they provide the following benefits:

• Ray Traced Shadows
• Ray Traced Reflections
• Ray Traced Translucency
• Ray Traced Ambient Occlusion
• Ray Traced Global Illumination

The Automotive Configurator sample makes use of ray tracing for shadows, reflections, and ambient occlusion. Ray traced shadows simulate soft area lighting effects and were important to creating contact shadows on different parts of the car, such as the headlights. Along with ray traced ambient occlusion, they create a more realistic shadow of the car and ground it in the environment. Ray traced reflections make it possible for the environment to reflect off the car from all angles. Something that was limited with Screen Space Reflections.

For more information on using Real-time Ray Tracing, please see our Real-time Ray Tracing documentation.

Volumetric Clouds

The Volumetric Clouds found in the sample use a physically-based cloud rendering system and a material-driven approach to create the sky that is seen on the salt flats.

The Epic Games team uses volumetric clouds to bring aesthetic touches to the salt flats, while also getting bounced light reflection on the car paint. The Volumetric Cloud component uses a Material Instance of the default cloud Material to accomplish these effects.

For more information on using the Volumetric Clouds system, please see our Volumetric Clouds documentation.

Control Rig

The Control Rig system is a scriptable node-based rigging system that provides rigging and animation tools directly in the engine.

In the Automotive Configurator, the Epic Games team uses Control Rig in two ways. The first is to create a very adaptable skeletal mesh version of the car and create the animations for the wheels, doors, and trunk. The second is to create the animation for the convertible top.

For the Audi A5, a skeleton featuring pivot locations for each movable element is created and bound to only a single polygon. With this method, the main vehicle geometry does not need to be bound to the vehicle and the skeletal mesh can be imported into Unreal quickly. Once imported, the mesh is added to a Blueprint and the rest of the vehicle components are attached to the pivots. The Control Rig is bound to the skeleton at runtime. This makes it easier to update the pivot locations if needed without having to go back to our DCC application.

Due to its complexity, the cloth convertible top is created as a separate piece with its own skeleton and Control Rig. A state machine tracks if the top is open or closed, and runs the correct transition animation when it is selected in the configurator application.

For more information on using Control Rig to animate in-engine, please see our Control Rig documentation.

Sequencer

Powering the Commercial mode, Sequencer is a robust keyframe animation system in which users can create in-game cinematics:

The specialized multitrack editor contains user-defined Tracks. These tracks can contain a variety of animations, transformations, audio, and other varieties of data.

For the Commercial mode, a series of level sequences were created with animated cameras that showcase various configurable features on the car. The team then uses Movie Render Queue to render and save the level sequences and then assemble them using a non-linear editing program. This edited sequence is brought back into Unreal as a master sequence, where audio is added and the cameras, animation, and overall timing is refined.

For more information on using Sequencer in your projects, please see our Sequencer documentation.

Movie Render Queue

Used to output the final commercial render, Movie Render Queue is an engine feature that can output high-quality Sequence movies. When used with Real-Time Ray Tracing, the final output can take advantage of advanced anti-aliasing, radial motion blur, and reduced noise in ray tracing.

The Epic Games team uses Blueprint to enable Movie Render Queue at runtime. This allows for the rendering and saving of the commercial sequence directly from the configurator.

For more information on using the Movie Render Queue feature, please see our Movie Render Queue documentation.

Adding Art Assets to the Configurator

Adding new art assets to the Automotive Configurator can be done by adding a new variant to the Level Variant Set. This process is similar for both Materials and Static Mesh assets. In the example below, we will add a new paint color to the configurator.

The Audi A5 in this sample makes use of the Automotive Materials Pack for paint, leather, and trim options. To add an additional colors to the interface, follow these steps:

1. Create a custom folder to hold your new Material and any texture samples that it may need.
2. If you are not adding a color that is already available within the sample, you will need to either create your paint sample using the tools available within the Automotive Material Pack, or import and set up your Material. For more information on importing textures and creating new Materials, please see our Materials documentation.

3. Next, open the CarConfigurator/Shared folder and double click on the CarVariants Level Variant Set to open it.

   

4. To make sure that your new color is applied to all the required static meshes, you can duplicate an existing Variant. Open the Paint, Trim, or Leather Variant Sets and right click on the variant last variant in the list. From the menu, choose the Duplicate option.

   

5. Right click on your new variant and choose Rename. Create a new name that is appropriate for the color.

   

6. Now, click the B_AudiA5 in the Properties panel to display the Properties and Values for the car. For each value in the Values column, click the drop down menu and select your new color, excluding the SM_trunkDetails Material.

   

7. Lastly, set the thumbnail image for your new variant by switching on the variant and positioning the Viewport camera to best display your new option. Then right click the variant in the Variant Manager and choose the Set from viewport option.

   
8. Test the sample by clicking the Play button in the Editor. Your new variant should appear in the user interface.