To control when one Level Of Detail (LOD) Static Mesh transitions into another one, Unreal Engine 4 (UE4) uses the current size of the Static Meshes size in Screen Space. While this method of controlling LOD transitions works quite well the numbers used for one platform might not work for another one. In the following How - To we will take a look at customizing the LOD Screen Size for each platform your UE4 project can be used on.
Steps
In the following section we will take a look at how to specify the Screen Size at which LOD transactions should take place on a per platform basis.
- First, inside the Content Browser, locate a Static Mesh that has a few LODs to work with and open it up inside the Static Mesh Editor. For this example the Static Mesh that was selected has four LODs however you can pick one that has more or less depending on the needs of your project.
- Once the Static Mesh is open in the Static Mesh Editor, go to the Details Panel and expand the LOD Settings category.
- Disable the checkmark box next to Auto Compute LOD Distances so that we can manually set the distance at which LOD transition should take place.
- Next, go to the LOD Picker section and enable the Custom option by clicking on the checkmark box next to it. This will allow you to see all LODs at the same time in the Static Mesh editor.
- Expand the LOD1 section and next to the Screen Size option,click on the small white triangle to expose the option to add per-platform LOD overrides.
- From the displayed per-platform override list, select the Add Override for Mobile option.
- Repeat the above step for LOD 2 and LOD 3 and when completed your Details panel should look like the following image.
- You can now adjust the Mobile Screen size by inputting a new number in the box under the Mobile option. To figure out which screen size you should use for which LOD, the Viewport inside the Static Mesh Editor displays the Current Screen Size.
End Result
With the ability to override the distance at which LODs will transition on Mobile devices set, you can now go back and setup the transition distance for Console and PC using the exact same steps if that is required for your project. If you decide to do this then your LOD sections will look like the following image.
