DrakkenRidge: Building an open-world adventure for mobile VR | Unity

Further optimizations

When deciding how to optimize our rendering for mobile VR, we considered how each environment was built and chose the solution to best fit our needs.

In addition to ECS, we considered a variety of techniques, including LODs and impostors.

GameObject LODs

Rendering GameObjects with LODs consists of having multiple versions of a given object to be rendered at different distances from the player. For example, a highly detailed house model is swapped out for a very simplified low-poly version, saving on rendering time when the player is far away from the object.

In DrakkenRidge, every object is already modeled in a highly optimized low-poly retro art style, and the vast majority of the world is handled through ECS, so traditional 3D LODs would provide no real advantage.

However, the distance authoring system we created was built to handle rendering of LODs for distant Entities, when necessary.

Impostors

An impostor system takes 3D GameObjects and converts them into 2D billboards when the player is at a distance from them. This works best for dense, distant background objects such as forests. DrakkenRidge utilizes imposters in some situations.