灯光优化

You can disable shadow rendering for some surfaces or materials. For example, it can be done for the farthest LOD surface (when the shadows don't matter).您可以禁用某些表面或材质的阴影渲染。例如，它可以针对最远的 LOD 表面（当阴影无关紧要时）完成。

To disable shadow rendering for a surface:要禁用表面的阴影渲染：

1. In the World Hierarchy window, choose the node and go to the Surfaces section in the Node tab of the Parameters window.在 World Hierarchy 窗口中，选择节点并转到 Parameters 窗口的 Node 选项卡中的 Surfaces 部分。

2. Select the required surfaces and toggle the Cast Proj and Omni Shadows parameter off. To disable shadows from the world light, toggle the Cast World Shadows parameter off.选择所需的曲面并关闭 Cast Proj and Omni Shadows 参数。要禁用世界光的阴影，请关闭 Cast World Shadows 参数。

   

To disable shadow rendering for a material:要禁用材质的阴影渲染：

1. In the Materials Hierarchy window, choose the material and go to the Common tab of the Parameters window.在 Materials Hierarchy 窗口中，选择材质并转到 Parameters 窗口的 Common 选项卡。

2. Toggle the Cast Proj and Omni Shadow parameter off. To disable shadows from the World Light, toggle the Cast World Shadow parameter off.关闭 Cast Proj and Omni Shadow 参数。要禁用 World Light 的阴影，请关闭 Cast World Shadow 参数。

   

Dynamic lighting ensures that all shadows from moving light sources cast by moving objects are rendered correctly. This approach implies that geometry of your scene is rendered one more time each frame to calculate shadows for each Projected light source (or six more times — for each Omni). Using multiple dynamic lights in the scene and calculating shadows for them on the fly may cause a performance drop, especially when the scene contains complex geometry with lots of polygons. It can be a terrible waste of resources, when most objects and lights are static.动态照明可确保正确渲染移动物体投射的移动光源的所有阴影。这种方法意味着场景的几何图形每帧再渲染一次，以计算每个 Projected 光源的阴影（或每 Omni 多六次）。在场景中使用多个动态灯光并动态计算它们的阴影可能会导致性能下降，尤其是当场景包含具有大量多边形的复杂几何体时。当大多数物体和灯光都是静态的时，这可能会严重浪费资源。

It’s better to avoid dynamic shadows and use baked ones for everything static wherever possible. You can replace dynamic Omni and Projected Light sources with static ones (shadows for them are precomputed and stored in depth textures).最好避免动态阴影，并尽可能对所有静态阴影使用烘焙阴影。您可以将动态 Omni 和 Projected 光源替换为静态光源（它们的阴影已预先计算并存储在深度纹理中）。

Types of shadows to be rendered are defined by the light’s mode and shadow modes set for both lights and object surfaces.要渲染的阴影类型由灯光模式和阴影模式为两者设置灯和物体表面.

Depending on your needs, you can choose to render baked shadows only, or combine rendering of both baked and dynamic ones. The table below shows all possible variants of shadow settings.根据您的需要，您可以选择仅渲染烘焙阴影，或结合渲染烘焙阴影和动态阴影。下表显示了阴影设置的所有可能变体。

Thus, for a Dynamic light, shadows from all lit objects are rendered as dynamic.因此，对于动态光，来自所有被照亮对象的阴影都被渲染为动态的。

For a Static light in Static shadow mode, only baked shadows from objects with Mixed shadow mode are rendered; dynamic shadows are not rendered at all.对于 Static 阴影模式的静态光，仅渲染来自具有 Mixed 阴影模式的对象的烘焙阴影；根本不渲染动态阴影。

For a Static light in Mixed shadow mode, both types of shadows are rendered: baked (from surfaces with Mixed shadow mode) and dynamic (from surfaces with Dynamic shadow mode). 对于 Mixed 阴影模式下的静态光，两种类型的阴影都会被渲染：烘焙（来自具有 Mixed 阴影模式的表面）和动态（来自具有 Dynamic 阴影模式的表面）。

Mixed mode implies that the dynamic shadow map is copied into the static depth texture and the result is rendered. If you select a higher resolution, the process of copying the shadow map can take time and affect performance. Therefore, 4K resolution in the Mixed shadow mode makes sense if the scene has more than 1.5 million triangles, otherwise Dynamic mode may be faster. Moreover, pay attention to video memory consumption, as a single 4K resolution depth texture for an omni light takes about 400 MB.混合模式意味着将动态阴影贴图复制到静态深度纹理并呈现结果。如果选择更高解决，复制阴影贴图的过程可能需要时间并影响性能。因此，如果场景有超过 150 万个三角形，Mixed 阴影模式下的 4K 分辨率是有意义的，否则 Dynamic 模式可能会更快。此外，请注意显存消耗，因为泛光灯的单个 4K 分辨率深度纹理大约需要 400 MB。

注意

If shadows from static light sources are not rebaked automatically, use the Bake Lighting tool.如果来自静态光源的阴影没有自动重新烘焙，请使用 Bake Lighting 工具。

The World Light source works in a similar way, but it uses shadow cascades. In Dynamic mode, shadow cascades are built dynamically relative to the camera's position, while in Static, they are baked and have their area defined by the light source's position. Static mode of the World Light is suitable as a performance optimization technique for small-area ArchViz projects where shadow cascades can be divided into two sections: walkable area with high-resolution shadows (as they're observed closely) and non-walkable area with low-resolution shadows (as they're observed from a distance). Note that changing the time of day is not available in Static mode, as shadow cascades are baked.World Light 源以类似的方式工作，但它使用阴影级联.在 Dynamic 模式下，阴影级联是相对于相机的位置动态构建的，而在 Static 模式下，它们是烘焙的，并且它们的区域由光源的位置定义。 World Light 的 Static 模式适合作为小区域 ArchViz 项目的性能优化技术，其中阴影级联可分为两个部分：具有高分辨率阴影的可步行区域（因为它们被仔细观察）和不可步行区域低分辨率阴影（从远处观察）。请注意，在 Static 模式下无法更改时间，因为阴影级联已烘焙。

注意

The Cached Shadows video tutorial illustrates how to set and use dynamic and static shadows.这Cached Shadows 视频教程说明了如何设置和使用动态和静态阴影。

A Shadow mask allows you to control rendering of shadows. You can specify which surfaces lit by a light source should cast shadows:Shadow 掩码允许您控制阴影的渲染。您可以指定由光源照亮的表面应该投射阴影：

1. For a light source, specify the Shadow mask: open the World Hierarchy window and select your light source. In the Shadow Mask section of the Node tab in the Parameters window, specify the shadow mask.对于光源，指定 Shadow 掩码：打开 World Hierarchy 窗口并选择您的光源。在 Parameters 窗口的 Node 选项卡的 Shadow Mask 部分中，指定阴影遮罩。

   

2. For all surfaces that are lit by the light source and should cast shadows, specify the Shadow mask that matches the light source's Shadow mask (one bit at least).对于由光源照亮并应投射阴影的所有表面，指定与光源的 Shadow 遮罩匹配的 Shadow 遮罩（至少一位）。
3. For all materials applied to such surfaces, specify the matching shadow mask as well.对于应用于此类表面的所有材质，还要指定匹配的阴影遮罩。

注意

An example of using shadow masks is available in the Content Optimization video tutorial.使用阴影蒙版的示例可在Content 优化视频教程。

For all types of light sources, screen-space shadows can be rendered instead of the shadow maps at large distances. It improves the performance, as such shadows don't depend on complexity of the geometry.对于所有类型的光源，屏幕空间阴影可以代替远距离的阴影贴图进行渲染。它提高了性能，因为这样的阴影不依赖于几何的复杂性。

注意

Screen-space shadows depend on the screen resolution: the higher the resolution, the more accurate shadows are.屏幕空间阴影取决于屏幕分辨率：分辨率越高，阴影越准确。

You can enable screen-space shadows in one of the following ways:您可以通过以下方式之一启用屏幕空间阴影：

• In the Menu Bar, choose Rendering -> Shadows -> Screen Space Shadows.在菜单栏中，选择 Rendering -> Shadows -> Screen Space Shadows。
• In the Menu Bar, choose Windows -> Settings and then go to the Shadows section. Here you can toggle the Screen Space Shadows parameter on.在菜单栏中，选择 Windows -> Settings，然后转到 Shadows 部分。在这里您可以打开 Screen Space Shadows 参数。

You can also set up per-light screen space shadows in the type-specific tabs (Light World, Light Omni, etc.) of the Parameters window.您还可以在 Parameters 窗口的特定类型选项卡（Light World, Light Omni 等）中设置每个灯光的屏幕空间阴影。

Screen Space Shadow Settings of Omni LightOmni Light的屏幕空间阴影设置

All Omni and Projected light sources are subject to a common deferred optimization technique — the Scissor Test: for each light source a scissor rectangle is found to define its bounds and, therefore, the area of its influence. The scissor rectangle defines the size of the render target for the current light source, since everything that falls outside that region is not affected by the light at the current moment.所有 Omni 和 Projected 光源都采用一种常见的延迟优化技术 - Scissor Test：为每个光源找到一个剪刀矩形来定义其边界，从而定义其影响区域。剪刀矩形定义当前光源的渲染目标的大小，因为在该区域之外的所有内容都不受当前时刻的光线影响。

Enable the Scissors visual helper or use the render_show_scissors 1 console command to enable visualization of the Scissor Test.启用 Scissors 可视化助手或使用 render_show_scissors 1 控制台命令启用 Scissor Test 的可视化。

Scissor rectangles for Omni light sources用于 Omni 光源的剪刀矩形

Therefore, the size of a light source significantly affects the performance: the larger the screen area where the illuminated surface is rendered, the lower the light performance is. So, keep the size as small as possible.因此，尺寸光源的大小对性能有显着影响：被照面渲染的屏幕面积越大，光性能越低。所以，尽量保持尺寸小。

In this mode lighting is rendered during the Deferred pass in half resolution (1/4 of all pixels) with subsequent reconstruction of neighboring pixels using the data from previous frames, making it possible to reduce rendering load.在这种模式下，在延迟传递期间以半分辨率（所有像素的 1/4）渲染照明，随后使用来自先前帧的数据重建相邻像素，从而可以减少渲染负载。

Interleaved Lights Rendering settings交错灯光渲染设置

For more details refer to the Interleaved Lights Rendering article.有关详细信息，请参阅交错灯光渲染文章。

You can control rendering of light sources and cast shadows by specifying the visibility distances.您可以通过指定 visibility distances 来控制光源的渲染和投射阴影。

The global settings for all light sources (World, Omni, Projected) can be specified in the Visibility Distances section of the Settings window.可以在 Settings 窗口的 Visibility Distances 部分中指定所有光源 (World, Omni, Projected) 的全局设置。

Non-opaque geometry is shaded on the Forward pass of the Rendering Sequence. Since all light sources are applied to each transparent surface in a cycle, it is highly recommended to keep the number of lights affecting transparent objects as low as possible for optimal performance.不透明几何图形在渲染序列的 Forward 通道上着色。由于所有光源都在一个循环中应用于每个透明表面，因此强烈建议将影响透明对象的灯光数量保持在尽可能低的水平，以获得最佳性能。

Global Lights Settings include Forward Per-Object Limits where you can limit the number of certain light sources that affect each transparent object at a time.全局灯光设置包括 Forward Per-Object Limits，您可以在其中限制一次影响每个透明对象的某些光源的数量。

If your scene contains water object(s), you can disable rendering the light from the light source on them. It will significantly increase the performance.如果您的场景包含水对象，您可以禁用在它们上渲染来自光源的光。它将显着提高性能。

1. Select a light source in the World Hierarchy.在 World Hierarchy 中选择一个光源。

   

2. In the Parameters window, go to the Render section and toggle the Water parameter off.在 Parameters 窗口中，转到 Render 部分并关闭 Water 参数。

   

Billboards can be used to simulate small light sources observed from large distances. In such cases, only visualization of light sources matters. For example, you can use Billboards for takeoff runway lights. They don't produce any light, but look like real lights.Billboards 可用于模拟从远距离观察到的小光源。在这种情况下，只有光源的可视化很重要。例如，您可以将 Billboards 用于起飞跑道灯。它们不产生任何光，但看起来像真正的光。

Billboards Used for Takeoff Runway Lights用于起飞跑道灯的广告牌

To create Billboard that replaces a real light source, perform the following:要创建替换真实光源的 Billboard，请执行以下操作：

1. Add a Billboard object to the scene by choosing Create -> Billboards -> Base in the Menu Bar and place it somewhere in the world.通过在菜单栏中选择 Create -> Billboards -> Base 将 Billboard 对象添加到场景中，并将其放置在世界的某个位置。

   

2. Assign a material inherited from the billboards_base material.分配从 billboards_base 材质继承的材质。

3. Specify the following settings for this material:为此材质指定以下设置：

   1. In the Common tab, set the blending Preset to Additive and toggle the Depth Write parameter off to avoid obstructing objects behind the Billboard.在 Common 选项卡中，将混合 Preset 设置为 Additive 并关闭 Depth Write 参数以避免遮挡 Billboard 后面的对象。

      

   2. In the States tab, disable writing into the Deferred Buffers and enable the following states:在 States 选项卡中，禁用写入 Deferred Buffers 并启用以下状态：

      • Emission to provide the emission effect by using the corresponding texture.Emission 通过使用相应的纹理来提供发射效果。
      • Geometry Inflation to limit the minimum Billboard screen size to a fixed value and, therefore, to provide visibility from far distances.Geometry Inflation 将最小 Billboard 屏幕尺寸限制为固定值，因此，提供远距离可见性。
      • Soft Interaction to make interaction of the Billboard with other objects in the scene softer and avoid artifacts.Soft Interaction 使 Billboard 与场景中其他对象的交互更柔和并避免伪影。

      

   3. In the Textures tab, specify the Diffuse and Emission textures.在 Textures 选项卡中，指定 Diffuse 和 Emission 纹理。

      

   4. In the Parameters window, specify the following values:在 Parameters 窗口中，指定以下值：

      • Set the Diffuse color multiplier to black, so that Billboard become fully transparent.将 Diffuse 颜色乘数设置为black ，使 Billboard 变得完全透明。
      • Increase the Emission Scale to make Billboard brighter.增加 Emission Scale 使 Billboard 更亮。
      • Increase the Geometry Parameters to scale the size of Billboard and limit the minimum size of Billboard.增加几何参数缩放 Billboard 的大小并限制 Billboard 的最小大小。
      • Correct the Soft Interaction value, if necessary.如有必要，更正 Soft Interaction 值。

      

As a result, you get the Billboard that can be used to simulate a small light source at far distances. You can add any required number of Billboards to the existing Billboard object: in the Parameters window, select the created Billboard in the list and click Add.结果，您获得了可用于模拟远距离小光源的 Billboard。您可以将任何所需数量的 Billboards 添加到现有的 Billboard 对象中：在 Parameters 窗口中，选择列表中创建的 Billboard 并单击 Add。

Lights Simulated by Billboards广告牌模拟的灯光

Volumetric objects can be used to simulate visible light volumes instead of using real light sources. Such objects should be used when you don't need illumination. For example, by using Volumetric objects, you can create light spheres, beams, or volumes, imitate sun beams falling into a room through openings, and so on.Volumetric 对象可用于模拟可见光体积，而不是使用真实光源。当您不需要照明时，应使用此类对象。例如，通过使用 Volumetric 对象，您可以创建灯光球体,梁， 要么卷, 模仿太阳光束通过开口落入房间，等等。

Light sphere and beam simulated instead of real light source模拟光球和光束而不是真实光源

To create such light volumes, perform the following:要创建此类轻量级，请执行以下操作：

1. Add the Volume Sphere object by choosing Create -> Volume -> Sphere Light in the Menu Bar and make it a child of the node that should emit the light.通过在菜单栏中选择 Create -> Volume -> Sphere Light 添加 Volume Sphere 对象，并使其成为应该发光的节点的子节点。

   

2. In the Volume Sphere section of the Parameters window, change the size of the sphere to 0.15.在 Parameters 窗口的 Volume Sphere 部分，将球体的大小更改为 0.15。

3. In the Node tab of the Parameters window, set coordinates of the volume sphere to the parent node and then slightly correct the sphere position, so that it looks realistic.在 Parameters 窗口的 Node 选项卡中，将体积球体的坐标设置为父节点，然后稍微修正球体位置，使其看起来更逼真。

   

4. Assign a material inherited from the volume_light_base base material and specify the required values in the Parameters tab. For example, you can set the color of the light sphere and scale the density of the light.分配从 volume_light_base 基础材质继承的材质，并在 Parameters 选项卡中指定所需的值。例如，您可以设置颜色光球和缩放密度的光。

   

5. Add the Volume Projected object by choosing Create -> Volume -> Projected in the Menu Bar and make it a child of the node that should emit the light.通过在菜单栏中选择 Create -> Volume -> Projected 添加 Volume Projected 对象，并使其成为应该发光的节点的子节点。

   

6. In the Node tab of the Parameters window, reset the position and rotation of the Volume Projected to the parent node ones.在 Parameters 窗口的 Node 选项卡中，将 Volume Projected 的位置和旋转重置为父节点的位置和旋转。

   

7. In the Volume Projected section of the Parameters window, specify the required parameters of the light beam. For example, change its size, radius, field of view, and step.在 Parameters 窗口的 Volume Projected 部分，指定光束所需的参数。例如，改变它的尺寸、半径、视野和步长.

   

8. Assign a material inherited from the volume_proj_base base material.分配从 volume_proj_base 基础材质继承的材质。

9. In the Parameters window of the material, set the color of the light beam the same as for the Volume Sphere and decrease the diffuse scale to 0.5 to make the color less bright.在材质的 Parameters 窗口中，设置颜色光束与 Volume Sphere 相同，并减少弥散尺度到 0.5 以使颜色不那么明亮。

   

As a result, you get a light sphere and a beam imitating the real light source.结果，您会得到一个光球和一个模仿真实光源的光束。

Light simulated by Volume Sphere and Volume Proj objects由 Volume Sphere 和 Volume Proj 对象模拟的光