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, Additional Settings, 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

属性		描述
Unit Conversion		Apply a global scale to the imported SpeedTree model. The default setting is ft to m because the SpeedTree Modeler uses feet and Unity uses meters as world units.
	Leave As Is	Don’t apply any unit conversion. Interpret the values in the model file as meters.
	ft to m	Convert from feet to meters.
	cm to m	Convert from centimeters to meters.
	inch to m	Convert from inches to meters.
	Custom	Apply a user-specified scale factor to the model.
Scale Factor		Scale the model by a custom value. This property is visible only when Unit Conversion is set to Custom.

Material

属性	描述
Main Color	Choose a color to modulate the diffuse lighting component.
Color Variation	Enable color variation for the model. This property uses Main Color and Variation Color (RGB) Intensity (A) along with the model’s world position to pick the final color. Color variation helps add a more natural look to clusters of SpeedTree models.
Variation Color (RGB), Intensity (A)	Choose the color and intensity used in the Color Variation process. This property is visible only when Color Variation is enabled.
Normal Map	Enable Bump maps on the model.
Subsurface Scattering	Enable subsurface scattering effects. This shader effect simulates the light scattered out the back side of leaves and other two-sided SpeedTree materials.

光照

属性	描述
Cast Shadows	Let the model cast shadows on its environment when directly lit by a light source.
Receive Shadows	Let the model receive shadows from other GameObjects in the scene.
Light Probes	Enable Light Probes rendering for the model.

Additional Settings

属性		描述
Motion Vectors		Set the Motion Vector property for the Mesh Renderer of each LOD GameObject. For details about the motion vector rendering options, refer to the Mesh Renderer component.

Wind

属性		描述
Wind Quality		Choose the level of wind quality to use for this asset. Options with more wind effects have a higher performance cost.
	无	No wind effects.
	Fastest	Global sway is applied to the model.
	Faster	Global sway and leaf ripple are applied to the model.
	Better	Global sway, branch motion, and leaf ripple are applied to the model.
	Best	Global sway, branch motion, leaf ripple, and leaf tumbling are applied to the model.
	Palm	Global sway, branch motion, leaf ripple, leaf tumbling, and frond ripple are applied to the model.

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.