HullAccumulator

This transformer accepts both 2D and 3D features, but the z coordinates of 3D features will be ignored during the calculation of the hull. Depending on the value of the输出parameter, the convex hull of 3D features may be a polygon that uses unmodified 3D vertices from the input features. This may result in a polygon with varying z coordinates.

Arcs and ellipses will be stroked prior to the calculation of the hull. Text features will be treated as points.

A feature representing the requested hull. Typically a polygon, but possibly a line or a point.

具有非数字属性的功能AlphaandDefault Z Value

Rejected features will have anfme_rejection_code属性包含以下值之一：INVALID_GEOMETRY_VERTICES那INVALID_PARAMETER_ALPHA_VALUE那INVALID_PARAMETER_DEFAULT_Z_VALUE。

如果Group By指定了属性，然后针对对所有这些属性的每组输入功能生成船体输出功能。否则，输出代表所有输入特征的船体的单个特征。

这船体类型参数可以指定凸形或凹管。凸壳是多边形，其中内角大于180度。对于凹壳，此限制不适用。

凸壳被定义为最小封闭凸多边形。在奠定条款中，效果类似于拧紧特征周围的橡皮筋。注意，如果产生的多边形具有零区域，则凸壳可以是行或点。

凹壳，也称为alpha hull，基于Alpha Value范围。凹壳可以更接近地表示特征几何的轮廓而不是凸船体。凹壳可以由多个甜甜圈或多边形组成。

When theAlpha Value参数是specified, it is used in the alpha hull calculation directly; a larger number will generally produce larger areas. If a circle with a radius ofAlpha Valueground units is able to pass between two points A and B of the feature without touching any other points of the feature, then the resulting hull will not directly connect A and B. Geometries that are farther away thanAlpha Valuefrom the rest of the geometries may be culled (removed) if they do not constitute a valid area on their own. It is possible that a null geometry will be returned if the specified alpha was too small for the spacing of the geometry.

When theAlpha Value参数未指定或设置为0，近似于最佳alpha，它是生成单个区域的最小alpha，将用于生成凹管。凹入船体生成最佳地点，但是线条和区域几何形状将被接受并转换为点数输入。

Choose between 2D and 3D representation of coordinates of points in the hull.

When2Dis chosen, all z coordinates will be removed from any vertices in the output.

When3Dis chosen, the convex hull will be a polygon that uses unmodified 3D vertices from the input features. If there is a mixture of 2D and 3D vertices in the input features, then the 2D vertices will be converted to 3D using the specifiedDefault Z Value。However, if all input features are 2D, the output will not be converted to 3D.

2D vertices that are converted to 3D will use theDefault Z Value作为z协调输出参数是3D。