LOD Group component reference

The LOD Group component manages level of detailThe Level Of Detail (LOD) technique is an optimization that reduces the number of triangles that Unity has to render for a GameObject when its distance from the Camera increases. More info
See in Glossary (LOD) for GameObjectsThe fundamental object in Unity scenes, which can represent characters, props, scenery, cameras, waypoints, and more. A GameObject’s functionality is defined by the Components attached to it. More info
See in Glossary.

Controls for transitioning between LOD levels

LOD Group selection bar for switching between LOD levels and previewing LOD rendering

Information about the Lod Bias Quality setting. This message appears if the Lod Bias property is set to anything other than 1.

Fade Transition Width setting for the selected LOD level. This property only appears if you disable the Animate Cross-fading property: that is, when you choose to set a transition zone by width instead of time.

Mesh Renderers set for the selected LOD level

In addition there are two buttons at the bottom of the component:

• Click Recalculate Bounds to recalculate the bounding volumeA closed shape representing the edges and faces of a collider or trigger.
  See in Glossary of all LOD Mesh GameObjects after a new LOD level is added.
• Click Recalculate LightmapA pre-rendered texture that contains the effects of light sources on static objects in the scene. Lightmaps are overlaid on top of scene geometry to create the effect of lighting. More info
  See in Glossary Scale to update the Scale in Lightmap property on all LOD Mesh RenderersA mesh component that takes the geometry from the Mesh Filter and renders it at the position defined by the object’s Transform component. More info
  See in Glossary, based on the changes you made to the LOD level boundaries.

LOD Group selection bar

The LOD Group selection bar represents the different LOD levels as colored boxes.

The percentage that appears in each LOD level box represents the threshold at which that level becomes active, based on the ratio of the GameObject’s screen space height to the total screen height. For example, if the threshold for LOD 1 is set to 50%, then LOD 1 becomes active when the cameraA component which creates an image of a particular viewpoint in your scene. The output is either drawn to the screen or captured as a texture. More info
See in Glossary pulls back far enough that the GameObject’s height fills half of the view.

The playhead for the LOD preview. You can scrub the camera icon back and forth to test the LOD levels and their transitions. At the bottom of the playhead you can see the current percentage.

To select a level, click on the level box. For each LOD level you select, you can pick the Renderer to use or customize the transition zone.

To add and remove LOD levels from the selection bar, right-click the LOD level box and then choose Insert Before or Delete from the context menu.

Level adjustment control. To change the percentage value for the LOD level, drag the left border of the LOD level box’s boundary.

Note: If the Lod Bias property is not set to 1, the Camera position might not match the position where each LOD level actually transitions from the next. In this case, a warning message appears below the selection bar.

Previewing the LOD transitions

The SceneA Scene contains the environments and menus of your game. Think of each unique Scene file as a unique level. In each Scene, you place your environments, obstacles, and decorations, essentially designing and building your game in pieces. More info
See in Glossary view displays a preview of the transitions between LOD levels when you move the camera icon on the LOD Group selection bar. The camera icon acts like a playhead which you can use to scrub back and forth to control the exact position to preview along the LOD Group selection bar. The preview shows what the Camera will render at each LOD level.

The LOD preview playhead shows the exact position as a percentage along the LOD Group selection bar from 100% on the left to 0% on the right. The percentage represents the ratio of the GameObject’s screen space height to the total screen height.

As you move through the levels, the Scene viewAn interactive view into the world you are creating. You use the Scene View to select and position scenery, characters, cameras, lights, and all other types of Game Object. More info
See in Glossary displays the bounding box of the Tree Asset and the overlay indicates which LOD is active:

Note: Unity only displays the LOD label when a single GameObject is selected. It is not displayed when multiple GameObjects are selected.

Renderers for LOD Meshes

When you select an LOD level box on the LOD Group selection bar, a Renderers panel appears.

The ‘Renderers’ are actually GameObjects that hold the Mesh for that LOD level. Usually this is a child of the GameObject that has the LODGroup component.

To set a renderer Mesh for the current LOD level, click the Add box and choose the GameObject for that LOD level from the object picker.

You can choose any GameObject for the renderer, but if you choose a GameObject that isn’t already a child, Unity prompts you to parent it to the LODGroup GameObject.

LODGroup