截至目前，本章概述了BIM设计应用程序作为基于构件参数化设计工具而发展出来的基本功能。现在我们来看看主要的BIM设计应用程序以及它们的功能差异。目前为止，我们已经以单一的方式考虑了参数化建模应用程序，主要是作为工具生成设计信息，并可能用于构建和管理这些信息。当更加细化地考虑使用这些应用程序时，我们注意到大多数BIM设计应用程序不仅仅是设计工具。多数BIM设计应用程序也有与其它应用程序之间的接口，用于渲染、能耗分析、成本预算等等。有些应用程序也具有多用户功能以便能让多个用户协调彼此的工作。

当在机构内规划并开展BIM时，将它放在系统架构术语中来考虑是很有用的。在大多数机构中，BIM涵盖了多种应用程序用于不同使用目的。如何概念化和组织化这些不同的应用程序？大公司一般会支持并在某种意义上整合10——50种不同的应用程序供员工使用。

我们对已经长期非正式使用了的术语进行了明确，以从下列层次结构中考量BIM应用程序：

·BIM工具：可产出特定成果的专项应用程序；比如用于生成模型、出图、编写规范、成本预算、碰撞和错项检测、能耗分析、渲染、做计划以及可视化的工具。工具输出的内容往往是报告、图纸等独立的成果。然而，在某些情况下，工具输出就是导入到其它应用程序，例如用于成本预算的工程量提取和结构导入到节点深化应用程序。

·BIM平台：BIM平台通常是一种设计类应用程序，可生成数据用于多个使用目的。它能提供一个持有平台上信息的主要数据模型。多数BIM平台也内部整合了诸如出图和碰撞检测之类的功能。它们通常会根据不同的整合等级将接口与多个其他工具结合在一起。有些平台共用用户接口和交互类型。Digital Project就是以这种方式构建的（它的Structure、 Imagine 、Shape以及 System Routing这些工具就是在其系统内组织化的Workbenches）。

·BIM环境：它是一个或多个信息管道的数据管理，用于整合组织内的应用程序（工具和平台）。它支持机构内部信息的政策和实践。BIM环境往往是非概念化的并且是根据公司内部需要特别产生的。它们的显著应用点是多种BIM工具数据库的自动化生成和管理。同样，当使用多种平台以及多种数据模型时，就需要另一种层级的数据管理和协调。这些能处理人与人、平台与平台之间追踪和协调沟通方面的问题。BIM环境为承载除了模型数据之外其它更广泛的信息形式提供了机会，例如视频、图片、音频、电邮以及很多用于管理项目的其它信息形式。创建BIM环境不是为了管理那些不同的信息。第三章3.5节中谈论的BIM服务器是用于支持BIM环境的新产品。另外，BIM环境包含了可循环利用的构件和组件库、机构支持的应用程序接口以及整合管理和会计系统的链接。

BIM平台有足够的信息来支持构件的创建、编辑以及修改等设计操作。它们承载着能维持建筑模型正确性的参数化规则和其它规则。它们可能有多种内置工具用于3D建模、工程量提取、渲染以及出图。相反，BIM工具缺乏可正确更新建筑设计的架构和规则。BIM平台能分析、追踪和打包数据用于成本或规划以及生成规范，也可能生成渲染和动画。BIM平台通常也能非正式地作为BIM环境使用，例如依赖于一个平台在机构内提供所有的服务并为机构提供整合环境。平台供应商通过提供众所周知的"完整解决方案"促进了这一点。

截止目前，我们已经使用了通用术语“应用程序”，而没有区分这三种层次。在以后章节中，我们会明确地使用我们在本节中所定义的这三种概念（即BIM工具、BIM平台、BIM环境）。

This chapter has, so far, provided an overview of the basic capabilities of BIM design applications resulting from their development as object-based paramet- ric design tools. We now turn to reviewing the main BIM design applications and their functional differences. We have considered parametric modeling applications up to this point in a homogeneous manner, primarily as tools for generating design information, and possibly for structuring it and managing it. In considering their use in more detail, we note that most BIM design applica- tions aspire to be more than a design tool. Most BIM design applications also have interfaces to other applications, for rendering, energy analysis, cost esti- mation, and so forth. Some also provide multiuser capabilities that allow mul- tiple users to coordinate their work.

In planning and developing BIM within an organization, it is useful to think of it in system architecture terms. BIM, in most organizations, will involve multiple applications, for different uses. How are the different applications to be conceptualized and organized? Large firms will typically support and in some sense integrate 10 to 50 different applications for their employees’   use.

We make explicit use of some terms that long have been used informally,  to consider BIM applications in the following  hierarchy:

•   BIM tool: a task-specific application that produces a specific outcome;  example tools are those for model generation, drawing production, specifi- cation writing, cost estimation, clash and error detection, energy analysis, rendering, scheduling, and visualization. Tool  output is often standalone,  as reports, drawings, and so forth. In some cases, however, tool output is exported to other tool applications, such as quantity takeoffs to cost esti- ation, and structural reactions fed to a connection-detailing    application.

•   BIM platform: an application, usually for design, that generates data for multiple uses. It provides a primary data model that hosts the information on the platform. Most BIM platforms also internally incorporate tool functionality such as drawing production and clash detection. They typically incorporate interfaces to multiple other tools with varied levels of integra- tion. Some platforms share the user interface and style of interaction. Dig- ital Project is structured in this way, with its Structure, Imagine and Shape, and System Routing tools organized within their system as Workbenches.

•   BIM environment: the data management of one or more information pipelines that integrate the applications (tools and platforms) within an organization. It supports policies and practices of information within the organization. Often the BIM environment is not conceptualized and grows in an ad hoc manner by the needs within the firm. Automatic generation and management of multiple BIM tool datasets is their obvious use. Also, when multiple platforms are used, and thus multiple data models, another level of data management and coordination is required. These address tracking and coordinating communication between people as well as multiple platforms. BIM environments provide the oppor- tunity to carry much wider forms of information than model data alone, such as video, images, audio records, emails, and many other forms of information used in managing a project. BIM platforms are not set to manage such diverse information. BIM servers, reviewed in Chapter 3, Section 3.5, are the new products targeted to support BIM environments. In addition, the BIM environment includes object and assembly libraries for reuse, interfaces to the applications the organization supports, and links to corporate management and accounting systems.

BIM platforms have sufficient information to support design operations of object creation, editing, and modification. They carry parametric and other rules important for maintaining the correctness of a building model spatially. They may have multiple embedded tools for 3D modeling, quantity takeoff for rendering, and for drawing production. BIM tools, in contrast, lack the structure and rules for correctly updating the building design. They provide analyses, track and package data for costs or schedules, and generate specifications and possibly generate renderings or animations. Platforms are often also informally used as the BIM environment, relying on one platform to provide all the services within an organization and providing the integration environment for the organization. Platform vendors promote this, through their offering of the proverbial “complete solution.”

Up to this point, we have used the generic term application without distinguishing these three levels. In future chapters, we will use these concepts explicitly in the way they are defined here.