glTF Export Settings

导出设置

glTF Export Settings

导出设置

glTF (gl Transmission Format) is a free file format for 3D scenes and models. It was developed by the Khronos Group (www.khronos.org), a consortium of graphics companies - who also developed Collada. glTF is optimized for the efficient transmission and loading of 3D content that is used for real-time applications online (e.g., for use on Facebook and other social media).

glTF (gl 传输格式)是一种用于3D 场景和模型的免费文件格式。它是由 Khronos Group (www.Khronos. org)开发的，这是一个由图形公司组成的联盟，他们也开发了 Collada。glTF 优化了3D 内容的高效传输和加载，这些内容用于在线实时应用程序(例如，用于 Facebook 和其他社交媒体)。

In addition, many 3D engines such as Unity and Unreal can import this format. The Cinema 4D glTF exporter exports the Cinema 4D scene in the formats *.glft and glb, which are designed for use on all platforms with glTF support. You can test them by loading them in any one of the freely available glTF viewers online (e.g., https://gltf-viewer.donmccurdy.com).

此外，许多3D 引擎，如 Unity 和 Unreal 都可以导入这种格式。Cinema 4D glTF 出口商出口Cinema 4D 场景的格式 * 。Glft 和 glb，它们设计用于支持 glTF 的所有平台。你可以通过在任何一个免费可用的在线 gtf 查看器上加载它们来测试它们(例如，google https://glTF-viewer.donmccurdy.com )。

In addition to geometry, cameras, textures (these are coded in the file) and animations can be exported.

除了几何图形，相机，纹理(这些都在文件中编码)和动画可以导出。

Materials

材质

glTF materials adhere to a physically correct approach (’metallic roughness’) that is similar to a Physical material (New PBR Material) in the Reflectance channel (however, only 1 layer can be used!).

glTF 材质坚持一个物理上正确的方法(’金属粗糙度’) ，类似于物理材质(New PBR Material)在反射通道(但是，只能使用1层!).

In short, this means that glTF generally requires 3 settings that are extracted from a Cinema 4D material as follows (always incl. any defined textures and the respective Strength settings):

简而言之，这意味着 glTF 通常需要从 Cinema 4D 材质中提取3个设置，如下所示(总是包括。任何定义的纹理和相应的强度设置) :

• Base Color: 底色:Color 颜色 in the Color channel or 在颜色通道或Color 颜色 in the Reflectance channel (if both are defined, the former will prevail). 在反射通道(如果两者都被定义，前者将占优势)
• Metallic Value: 金属价值:Reflection Strength 反射强度 in the Reflectance channel. Here there is a difference between Cinema 4D and glTF: in Cinema 4D, this value defines the amount of light that is reflected by a surface. If set to 0%, a black surface would result. In glTF, this value defines the degree to which the reflectance behavior will reflect that of metal (white) or non-metal (black), i.e., this texture is mostly black/white. If the material is not metal, the 在反射通道里。这里 Cinema 4D 和 glTF 有一个区别: 在 Cinema 4D 中，这个值定义了表面反射的光量。如果设置为0% ，就会产生一个黑色的表面。在 glTF 中，这个值定义了反射行为反映金属(白色)或非金属(黑色)的程度，也就是说，这个纹理大部分是黑白的。如果材质不是金属，则Reflection Strength 反射强度 can also be set to 0%, which means that there will be a strong deviation between what you see in Cinema 4D and what glTF output. 也可以设置为0% ，这意味着你在 Cinema 4D 中看到的和 glTF 输出之间有很大的偏差
• Roughness Value: 粗糙度值:Width 宽度 in the Reflectance channel. 在反射通道里

If you load a texture into the Color or Reflectance channel, Multiply will be exported as the Mix Mode, whereby only the corresponding Brightness and Mix Strength will be evaluated. You should define these settings accordingly so you have a realistic preview in Cinema 4D of the colors that will be exported.

如果你加载一个纹理到颜色或反射通道，乘将导出为混合模式，只有相应的亮度和混合强度将被评估。你应该相应地定义这些设置，这样你就有了一个真实的预览在C4D 的颜色，将导出。

In addition, the following textures will be transmitted from Cinema 4D to glTF (and if useful, incl. the respective Strength setting that is defined):

另外，下面的纹理将从 Cinema 4D 传输到 glTF (如果有用的话，包括。定义的各自的强度设置) :

• Normal textures from the Reflectance channel or Normal channel (both Tangent type). If both are defined, the Reflectance channel will prevail. 来自反射通道或法线通道的法线纹理(都是切线类型)。如果两者都被定义，反射通道将占优势
• Occlusion textures from the Diffuse channel (here a baked Ambient Occlusion texture, for example, can be used). 来自漫反射通道的遮挡纹理(这里可以使用烘焙的环境遮挡纹理)
• Alpha textures from the Alpha channel. 阿尔法通道的阿尔法纹理
• Emissive textures and Emissive Factor/Color from the Luminance channel. For the latter, the 亮度通道的发射纹理和发射因子/颜色Brightness 亮度 setting will be read. 读取设置

The Transparency material channel uses the Brightness setting to simulate transparencies in glTF (the color comes from the Color channel or the Reflectance channel). This is simulated internally using the Alpha channel - refractions are therefore not supported. However, this only works with simple objects - ones that themselves don’t overlap in the angle of view - since display issues can otherwise be encountered.

透明材质通道使用亮度设置来模拟 glTF 中的透明度(颜色来自颜色通道或反射通道)。这是在内部使用 Alpha 通道模拟的，因此不支持折射。然而，这只适用于简单的对象——这些对象本身在视角上不会重叠——因为否则就会遇到显示问题。

Under https://medium.com/gametextures/metallic-magic-2dce9001fe15 you will find several interesting details about the Metallic Roughness workflow. We also need to mention that metal that is covered with a color or other material is not metal with regard to rendering.

在 https://medium.com/gametextures/Metallic-magic-2dce9001fe15下你会发现几个有趣的细节关于金属粗糙度工作流程。我们还需要指出的是，被彩色或其他材质覆盖的金属就渲染而言不是金属。

Remarks and Limitations

备注及限制

• Due to slightly different material concepts, Cinema 4D and glTF will produce different looks. Note the items described under 由于材质概念略有不同，Cinema 4D 和 glTF 将产生不同的外观。注意下面描述的项目Materials 材质 (in particular the Reflectance channel). You will most often have to make adjustments to the material! (特别是反射通道)。你经常需要对材质做一些调整
• When exporting textures, the 当导出纹理时,Texture Mode 纹理模式 in the Preferences menu will be used with regard to texture interpolation. 在参数设置菜单中将用于纹理插值
• If you get an error message in the glTF viewer resulting from glTF scenes exported from Cinema 4D, this will most likely be unproblematic because the scene will probably be displayed correctly. 如果从 Cinema 4D 导出的 gtf 场景在 gtf 查看器中得到错误消息，这很可能不会造成问题，因为场景可能会正确显示
• Instances are currently not supported and will be exported as normal geometry. 实例目前不受支持，将作为正常几何图形导出
• Node materials are currently not supported. 目前不支持节点材质
• In glTF, textures must have the same aspect ratio for 在 glTF 中，纹理的长宽比必须与Reflectance Strength 反射强度 and 及Roughness Strength 粗糙度强度 because they will be coded in a single bitmap on export. The same applies for textures for Color and Alpha. 因为它们在出口时会被编码在一个位图中。这同样适用于 Color 和 Alpha 的纹理
• When selecting a file name, 在选择文件名时,scene name 现场名称.gltftemp" will first be assumed. This name will be given the correct extension when it’s actually saved (and overwrite warnings prevented). .首先假设为“ gtfttemp”。当实际保存此名称(并防止覆盖警告)时，将为其提供正确的扩展名
• The 这个Texture Mode 纹理模式 will be recognized and exported. 都会被识别和输出
• Various materials on different polygon selections of the same object are supported. Internally, the selections will be subdivided into separate objects. 支持同一对象的不同多边形选区上的不同材质。在内部，选择将被细分为单独的对象
• When exporting, avoid assigning different materials to polygon objects to which joint animations are attached. The joint setup will not work correctly. 导出时，避免将不同的材质分配给附有联合动画的多边形对象。连接装置不能正常工作
• The exported animation length orients itself to the 导出的动画长度定位于Minimum Time 最短时间 and the 及Maximum Time 最长时间 setting in the Project Settings menu. 在项目设置菜单中设置