The 3D models and objects you import into Twinmotion are composed of three-sided polygons known as triangles. Objects with a high triangle count show a high level of detail but take more Graphics Processing Unit (GPU) resources to render in the viewport. To optimize rendering and overall scene performance when working in Twinmotion, you can use the Level of detail (LOD) feature to automatically decrease the number of triangles on distant objects in the scene based on viewport camera distance.
The LOD feature simplifies objects that appear far away from the viewport camera by reducing their triangle count. When an object is far away, such as a tree or a bush in a landscape, small details do not need to be displayed. As the object takes up more screen space in the viewport and gets closer to the camera, the complexity and level of detail increases progressively.
Applying LODs optimizes rendering in the viewport while you work in Twinmotion, but does not affect the level of details in exported media. For example, if you create an image while a LOD preset is applied to an object in the scene, the object will still render at 100% fidelity in the image.
Twinmotion offers the following LOD presets that generate varying amounts of LODs according to the complexity level you select:
Complex
Normal
Simple
The LODs are numbered and start at 0. LOD 0 is the highest quality LOD available and is identical to the original amount of triangles in an imported object. As the object moves closer or farther away from the camera, the LODs transition between each other automatically. You can also preview the visual aspect of LODs on objects and modify the complexity of the levels according to distance from the camera and triangle count.
You can use the LOD feature on all supported static geometry file types you import into Twinmotion. For information on supported file formats, see Supported Geometry File Formats in Geometry Overview.
Generating LODs
To generate LODs, follow these steps:
Import an object into Twinmotion. For more information on how to import geometry, see Importing Geometry.
Select the object in the viewport. The Level of detail section appears in the Properties panel.
In the Preset dropdown select a preset.
When you select a preset, the settings of the generated LODs appear in the Details section.
To apply the LOD preset, click Apply.
To preview the generated LODs on objects in the viewport, select the options in the Display LOD dropdown.
(Optional) You can modify the complexity levels of the LODs in the presets by using the sliders in the Screensize and Triangles tabs and then clicking Apply. You can then preview your changes using the Display LOD dropdown.
Level of Detail Settings
The following table describes the options in the Level of detail section.
| Setting | Description |
|---|---|
Preset | Select a preset to automatically apply a LOD recipe to the selected objects in the viewport. Each preset creates a specific amount of LODs according to the pre-configured settings in the LOD recipe. Options:
|
Display LOD | Select one of the options in the dropdown to preview the appearance of LODs on objects. Selecting an option shows how the LOD represents the object in the viewport. The number of LODs in the dropdown varies depending on the preset you select. More complex presets contain more LODs. Options:
|
| Details | |
Screensize | The level of detail used according to screen size. The Screensize value specifies the threshold at which LODs transition between each other. The threshold is determined by the percentage of screen space the object occupies in the viewport. Objects that are closer to the camera appear larger and occupy a larger percentage of the viewport area. For example, LOD 0 at 1.00 means the maximum amount of details are shown when the object occupies 100% of the screen space in the viewport. When you select a Preset, these values are set automatically but you can modify them. The number of LODs corresponds to the Preset you select. Options: 1.00 to 0.00, where 1.00 equals 100%. |
Triangles | The percentage of triangles used to represent the static mesh according to the LOD level. The higher the percentage, the more triangles are used. For example, LOD 0 at 100.00% means all the triangles in the mesh are used and visible. Options: 0.00 % to 100.00% |