Model 选项卡

Use the Model tab to change the model settings for imported SpeedTree assets.

To change materials settings for the SpeedTree model, see the Materials tab.

The Model tab has these sections:

(A) The Meshes, Material, Lighting, and Wind sections allow you to adjust global import settings for the model.

(B) The LOD section has a specialized variation of the LOD Group component for importing SpeedTree models. You can set smooth transitions between LOD levels, adjust thresholds for each LOD level, and use the level-specific LOD options to turn off resource-heavy effects.

(C) The Revert and Apply options always appear, but you can only select them after you make changes to the import settings. If you change settings in the Remapped Materials section of the Materials tab, the Apply & Generate Materials option appears.

(D) The properties for the GameObject (read-only) appear at the bottom of the Inspector view, including a preview of the SpeedTree Model.

Meshes

Material

光照

Wind

LOD

Note: This section assumes you have already read the documentation on the LOD Group component. The section on Working with SpeedTree Models explains key concepts and workflow information that are crucial for understanding how to import SpeedTree models.

The LOD Group component for the SpeedTree Importer is different from the generic LOD Group component that appears on a SpeedTree instance in Unity:

• Fade Mode options aren’t available because the Fade Mode is already set to Speed Tree.
• The playhead for the preview is missing because you can only preview the LOD transitions when an instance of the model is placed in the scene.
• The options governing the LOD transitions are the same as the LOD Group component, with the only difference being the Smooth Transitions property. Enable Smooth Transitions to reveal the other properties for LOD transition animations: Animate Cross-fading, Crossfade Width, and Fade Out Width.
• Each LOD level has its own set of options that allow you to enable or disable resource-heavy effects.

The LOD Group selection bar

LOD 组选择条将不同的 LOD 级别表示为彩色框。选择一个级别框后，其周围会出现蓝色轮廓：

每个 LOD 级别框中显示的百分比表示激活该级别的阈值。该阈值基于游戏对象的屏幕空间高度与屏幕总高度之比。

To select a level, click on the level box. To change the percentage value for a level, drag the boundary to the left or right of the level container. You can also customize which properties are enabled or disabled on each level as an optimization strategy.

Level-specific LOD options

For each LOD level defined on your SpeedTree asset, you can customize a variety of properties. The properties correspond to other settings in the Model tab and override global import settings.

To set LOD options on a specific LOD level, select the LOD level box on the LOD Group selection bar and enable Customize LOD options.

When you enable customization for an LOD level, the SpeedTree Importer generates a new material for that LOD level.

Note: Customized LOD levels negatively affect batching and instancing and increase memory consumption. But customizations can help with some GPU bottleneck scenarios if you disable shader-heavy effects for an LOD level. Profile your scene for CPU and GPU before and after you customize to see the impact on performance.

Billboard LODs

Billboards are treated differently from other LOD meshes:

• If billboards are available in the SpeedTree model, customizations are automatically enabled.
• Some resource-heavy properties such as Light Probes and Wind are disabled by default or have reduced value range for performance reasons.