A study of the built-in LOD Group component in Unity carried out by students Ludvig Arlebrink and Fredrik Linde at Blekinge Institute of Technology. This is supplementary material to the full report.
The Unity version used at the time was 2017.3.0f3 (64-bit). We use the Stanford bunny with LODs ranging from 0 to 4 for the experiment. We define five tests: LOD, Crossfade, Dither, No LOD and Empty. Where LOD, is a standard LOD test using the unity LOD group component, without any transitions. Both crossfade and dither also uses the LOD group component but with transitions enabled and set to crossfade. The no LOD does not use the LOD group component and renders the bunny on its maximum LOD. Finally, the empty test is just for reference and is a completely empty scene with a black clear color.
We began the implementation with creating Unity prefabs for each of the tests, except the empty test. For the LOD, crossfade and dither test, we add a LOD group component and for each LOD we add a child gameobject with a mesh renderer component for the LOD mesh. The No LOD prefab only includes a mesh renderer component with no children.
In the beginning of a test, we instantiate 20 bunnies of its corresponding prefab for each axis for a total size of 8000 bunnies. When the test is complete, we destroy all instances of the bunny and repeat this process until all tests have finished executing. At this point the application enters its final stage by running the empty scene test and automatically shuts down afterwards. We created a script for the camera to traverse a path defined by a number of points that the camera interpolates between given a constant speed at all times.
Fredrik Linde 