属性

    Note

    Attribute data types and domains are converted implicitly where possible, just like node sockets.

    Named attributes are created and used in other areas of Blender like shaders, painting, and UV mapping. In the modifier panel, a named attribute can be used for input by clicking the icon to the left of the value button. The string input input allows you to search and choose existing attributes from the modifier’s input geometry.

    Attribute Search.

    The attribute search gives a bit of context about each attribute. To the left of the menu, the attribute domain is shown followed by the attribute name. To the right of the menu, the attribute data type is shown.

    Anonymous Attributes

    ../../_images/modeling_geometry-nodes_attribute-reference_attribute-field.png

    The Normal and Rotation outputs are examples of attribute fields, which refer to an attribute stored on a geometry.

    An anonymous attribute is a set of generic data stored on a geometry that doesn’t have a name. Usually, attributes exposed in Blender’s interface all have names. However, in geometry nodes, attributes can be passed around with node sockets. In these cases, an Attribute Field output is created, which is used by nodes to find attribute data in an input geometry.

    Anonymous attributes are still stored on the geometry like other attributes, and they are even automatically interpolated when the geometry changes with other nodes, except for a few cases. So generally, if the node link is still accessible, the attribute it references will be too. However, anonymous attributes cannot be connected to a completely separate geometry that was not created from their source. To transfer attributes between separate geometries, the Transfer Attribute Node can be used.

    The type of an attribute is the kind of data stored at each element.

    The above list is in the order of least to most “complex” (An integer can contain more data than a boolean, so it is more complicated). When joining separate geometries together, the more complex data type is preferred when there are matching names. This is particularly important when joining geometry with named attributes with the

    Attribute Domains

    The domain of an attribute refers to what type of geometry element the attribute corresponds to. Knowing the domain of an attribute is important because it defines how it may be interpolated and used in nodes and shading. You can use the to determine the domains of attributes.

    • Point domain attributes are associated with single locations in space with a position:

      • Vertices of a mesh

      • Curve control points

    • Edge domain attributes are associated with the edges of a mesh.

    • Face domain attributes are associated with the faces of a mesh.

    • Face Corner domain attributes are associated with the corners of the faces of the mesh. An example is a UV map attribute.

    • Spline domain attributes are associated with a group of connected curve control points.

    Attributes are automatically interpolated to other domains. For example, when the 位置节点 is connected to the selection input of the node, the values are interpolated from the Point domain to the Face domain. Normally, domain conversions use simple averages for values, but Boolean data type attributes have special rules for interpolation:

    Built-in attributes always exist, and cannot be removed. Their data type and domain cannot be changed.

    Naming Conventions 命名习惯

    These attributes do not exist by default, but are used implicitly by certain parts of Blender. The data type of these attributes can be changed, just like any attribute besides the built-in attributes. However, the attributes might be expected by Blender to have a certain type.

    Vertex groups, UV maps and vertex colors are available as attributes in geometry nodes. They are referred to by their name. Naming collisions (e.g. a vertex group and a UV map with the same name) should be avoided. If there is a naming collision, only one of the attributes is accessible in geometry nodes.

    Attributes with any other name can also be created by nodes, when the name is used for the first time.

    Note that geometry nodes does not always produce e.g. vertex groups if a node like is used. Similarly, if the data type of a vertex group attribute is changed from the initial “Float” type, the attribute will no longer be a vertex group.

    Attribute Conversion Operator

    This operator found in the Attributes panel of the property editor can change the domain or data type of an attribute.

    Due to ongoing development in the area of attributes, many areas of Blender can not yet work with the generic (identified with a name, stored on any domain with any data type)attributes used by geometry nodes. That makes this operator an essential workaround in some cases where existing tools must be used with data generated from geometry nodes.

    模式

    • 泛型

      Inerpolate and convert the attribute between the domains and data types described on this page.

      UV映射

      Create a layer, editable in the UV editor. These would otherwise be represented by a 2D vector attribute on the face corner domain.

      顶点组

      Create a Vertex Group from the attribute, which corresponds to a float attribute on the point domain.

      顶点颜色

      Create a from the attribute, which, despite it’s name, corresponds to a color attribute on the face corner domain.

    Note