Volumes

体积

Various uses for OpenVDB. Clockwise from top left: Implemented twice with Boolean functions (the cross is made up of simple primitives affected by a Deformer), text with a Reshape Filter and finally with a fluid. OpenVDB 的各种用途。左上顺时针: 实现两次布尔函数(交叉是由简单的原语影响变形) ，文本与重塑过滤器，最后与流体

Until now, Cinema 4D almost only focused on an object’s surface for specifications - a polygon object is defined by the coordinate values and its surface points, which define the respective polygons. This is adequate for solid objects but for other objects such as fluids, fog or fire, this approach doesn’t work as well. These objects do not have an easily definable solid surface but a volumetric surface that often changes rapidly. Such effects can be better described as Voxels.

到目前为止，Cinema 4D 几乎只关注物体表面的规格——一个多边形物体是由坐标值和它的表面点定义的，这些坐标值和表面点定义了各自的多边形。这对于固体物体来说是足够的，但是对于其他物体，如液体、雾或火，这种方法并不起作用。这些物体没有一个容易定义的固体表面，但体积表面往往变化迅速。这种影响可以更好地描述为体素。

What are Voxels? Simply put, they are three-dimensional pixels. Similar to bitmaps, which are made up of two-dimensional pixels that each contain a color value, Voxels are arranged in a three-dimensional, cube-shaped grid that also contains a value (this can, for example, be the distance from a surface of a volume-generating object (Volume TypeSigned Distance Field) (SDF) or, for more complex, imported applications, the temperature or gaseous density of a flame, for example (Volume TypeFog).

什么是体素？简单地说，它们是三维的像素。与位图类似，位图由二维像素组成，每个像素都包含一个颜色值，体素被安排在一个三维立方体形状的网格中，网格中也包含一个值(例如，这可以是一个产生体积的物体(体积排列的距离场)的表面距离，或者，对于更复杂的进口应用，火焰的温度或密度，例如体积排列的雾)。

At left, a Torus defined by polygons; at right 1 element, respectively, marked. Depending on the definition, the Torus can be filled completely with Voxels as on the right (Fog) or with only Voxel layers near the surface (SDF). 在左边，由多边形定义的环面; 在右边的1个元素，分别标记。根据定义，环面可以完全用体素填充，如在右边(雾)或只有体素层附近的表面(SDF) Tip: 提示:
Per definition, OpenVDB differentiates between active and inactive Voxels (the scene is initially completely filled with inactive Voxels that use no memory; as soon as you create a volume, the respective Voxels will be activated). 根据定义，OpenVDB 区分了活动体素和非活动体素(场景最初完全充满了不使用内存的非活动体素; 一旦你创建了一个体积，各自的体素将被激活)

This differentiation is not referenced in the following descriptions. When Voxels or Voxel Layers are discussed, it will always be referencing active Voxels.

下面的描述中没有提到这种区别。当讨论体素或体素层时，它总是引用活动的体素。

With the introduction of R20, Cinema 4D can also work with Voxel-defined objects (for this, the Oscar Award-winning open source library OpenVDB was integrated). Voxels can be converted to polygon objects or polygon objects to Voxels at any time.

随着 R20的引入，Cinema 4D 也可以使用体素定义的对象(为此，奥斯卡获奖开源库 OpenVDB 被集成)。体素可以转换为多边形对象或多边形对象的体素在任何时候。

Note the new topology on the right compared to the original object on the left. 注意，右边的新拓扑与左边的原始对象相比较

Some tasks (e.g., Boolean operations) can be executed more effectively using Voxels than with polygon objects. This is why the conversion works smoothly in both directions.

有些任务(比如布尔操作)可以使用体素比使用多边形对象更有效地执行。这就是为什么转换在两个方向都能顺利进行的原因。

The Volume Mesh... command can be used to only modify the polygon topology (remeshing).

体积网格... 命令只能用于修改多边形拓扑(重新网格化)。

Note that modeling with Voxels is very restricted. Very precise modeling is very difficult (the Voxel Size would have to be very small, which in turn requires a lot of computing power). Nevertheless, fully parametric complex shapes can be easily created.

请注意，使用体素进行建模是非常有限的。非常精确的建模是非常困难的(体素尺寸必须非常小，这反过来又需要大量的计算能力)。然而，完全参数化的复杂形状可以很容易地创建。

To render Voxels they must be converted to polygon surfaces (see Volume Mesher).

为了渲染体素，他们必须转换成多边形表面(见体积介绍)。

Voxels can be created in the following way in Cinema 4D:

体素可以通过以下方式在C4D中创建:

From Cinema 4D objects using the 从C4D 物体使用Volume Builder.
By loading a *.vdb file (OpenVDB) 通过加载 * . vdb 文件(OpenVDB)

Voxels can, by the way, not only be used for modeling but also to create Volume Vectors. Each Voxel will then contain one vector.

顺便说一下，体素不仅可以用于建模，还可以用于创建体积矢量。每个体素将包含一个矢量。

Clear Cached Volumes

清除缓存体积

If this command is called up, the content of all cache layers in the Volume Builder will be deleted, regardless of whether or not they are activated (reflects what happens if the Delete button is clicked for each Volume Builder). The Volume Builder will then again be calculated live.

如果调用此命令，体积生成器中所有缓存层的内容将被删除，而不管它们是否被激活(反映单击每个体积生成器的 Delete 按钮会发生什么)。然后，体积生成器将再次计算生活。

第三体积

音量过滤器

体积对象

体积装载机

音量组