建筑设备电子产品目录的数据结构. 第2部分: 几何学

[中文适用范围]： ISO 16757 的这一部分描述了建筑服务产品几何形状的建模。 该描述针对产品目录数据的交换进行了优化，包括 — 用于表示产品本身的形状， — 在示意图中用于产品功能可视化的符号形状， — 用于功能需求的空间， — 用于可视化的表面，以及 — 用于表示不同对象之间连接的端口等等。 形状和空间几何被表示为基于通过布尔运算连接到边界表示的几何基元的构造实体几何（CSG）。 ISO 16757 的这一部分使用 ISO 10303-42 和 ISO 16739 中的适用原语，并添加了建筑服务产品的特殊几何形状所需的原语。 对于象征性形状，也使用线条元素。 ISO 16757 的这一部分既没有描述产品的内部结构和内部功能，也没有描述制造信息，因为这通常不会在产品目录中发布。 建筑服务产品可以有数百万种不同的尺寸。 为了避免交换数百万个几何形状，引入了参数化模型，该模型允许从通用模型中导出特定于变量的几何形状。 这对于将目录中要交换的数据减少到可管理的大小是必要的。 参数化模型将导致数据文件更小，在数据交换时更容易传输。 使用的几何模型不包含任何绘图信息，例如视图、线条样式或剖面线。 [外文原描述]： ISO 16757-2:2016 describes the modelling of building services product geometry. The description is optimized for the interchange of product catalogue data and includes - shapes for representing the product itself, - symbolic shapes for the visualization of the product's function in schematic diagrams, - spaces for functional requirements, - surfaces for visualization, and - ports to represent connectivity between different objects. The shape and space geometry is expressed as Constructive Solid Geometry (CSG) based on geometric primitives concatenated to boundary representations by Boolean operations. ISO 16757-2:2016 uses the applicable primitives from ISO 10303‑42 and from ISO 16739 and adds primitives which are required for the special geometry of building services products. For symbolic shapes, line elements are also used. ISO 16757-2:2016 neither describes the inner structure and internal functionality of the product nor the manufacturing information because this is typically not published within a product catalogue. Building services products can have millions of variant dimensions. To avoid the exchange of millions of geometries, a parametric model is introduced which allows the derivation of variant-specific geometries from the generic model. This is necessary to reduce the data to be exchanged in a catalogue to a manageable size. The parametric model will result in smaller data files, which can be easier transmitted during data exchanges. The geometry model used does not contain any drawing information such as views, line styles or hatching.