Design intent in surface modeling

在SolidWorks等参数化实体建模软件包中，设计意图的概念是设计应该反映用户的意图。其中一部分是对设计过程的要求。作为一个简单的例子，如果所需的对象具有镜像对称性，例如车身，用户应该设计对象的一半，然后反射这一半对象以获得另一半。这样做的好处是，如果用户稍后更改了对象的细节（例如在这个汽车示例中更改了前灯的样式），则只需对一个前灯而不是两个前灯进行更改。但是建模系统也应该尝试推断用户想要设计什么。例如，如果用户绘制一条直线并将其挤出，则用户最可能希望挤出为平面。

In a parametric solid modeling package such as SolidWorks, the idea of design intent is that the design should reflect the user's intent. Part of this is a requirement on the design process. As a simple example, if the desired object has mirror symmetry such as a car body, the user should design one half the object and then reflect this half object to obtain the other half. The benefit is that if the user later changes details on the object (such as changing the style of headlights in this car example), the change only needs to be made to one headlight rather than to two. But a modeling system should also try to infer what the user is trying to design. For example, if the user draws a straight line and extrudes it, the user most likely desires the extrusion to be a plane.