Rush Hour Version 1.2.0 Release Notes

Release Notes

About Rush Hour

Rush Hour is an AI-powered toolkit for animating vehicles. Using the realtime physics engine of Unreal Engine, an AI driver will pilot a physically simulated vehicle across a spline-based path. You can select a number of different profiles (Racer, Frantic, Slowpoke, etc) and a profile strength to influence how the AI will behave.

Version 1.2.0 (2023/05/14) notes

This major update brings a great deal of improvements. The highlight of this release is the initial release of the vehicle importer. This will drastically reduce the time it takes to get your vehicles into Unreal, and be driving them in Rush Hour. Note that this is optional, and standard Chaos Vehicles work just fine. Cornering is also significantly improved due to a reduction in corner cutting, and an improved measurement of a vehicles cornering ability.

Rush Hour Vehicle Toolkit

The vehicle importer currently requires you to prep the vehicle through Blender. Documentation on integrating with your own vehicle pipeline is coming soon.

Important note on Unreal Engine 4

Unreal Engine 4 support is no longer available. If you need UE4 support please reach out to me with your requirements at and I’ll see what can be arranged.

Additions & Fixes

  • Added Experimental Vehicle Importer
  • Updated tyre models and textures for the 3 included vehicles.
  • Reduced corner cutting, using a new method to project steering targets, vehicles should cut corners significantly less and stay much closer to the path
  • Resolved issue where vehicle would stop tracking progress along the path if it moved too far left or right of the path
  • Drastically improved cornering force measurement to be more consistent across more vehicles.
  • Added Unreal Engine 5.2 support
  • Fixed compilation issues with changes to IWYU in 5.2
  • Fixed issue in 5.2 where vehicles wouldn’t spawn

Upgrade Notes

Always remember to backup projects and the current plugin version before updating

Previously recorded sequences with the included vehicles will no longer work due to significant changes to the vehicle classes. You will need to re-record any sequences you wish to use.

Known Issues

  • Nanite vehicles exhibit shadow artifacts if using Ray Traced Shadows. Either disable nanite on vehicle meshes or disable raytraced shadows.
  • Newly Imported/Created assets from the Vehicle Importer may have incorrect thumbnails
  • Vehicle meshes that use more than 64 material slots are not able to use Nanite due to internal limitations of Nanite.
  • Reverse in Racer profile may exhibit over enthusiastic steering
  • Newly imported vehicles don’t have the correct “Use Legacy Wheel Friction Position” setting. Enable this on the vehicles VehicleMovementComponent to improve handling.