| 摘要 |
<p>An object-oriented system is used to manage tools and user interface with these tools in a geometric modeling system, such as a computer aided design (CAD) package. Tools are linked at start-up time, and each tool informs a tool manager which messages it should be sent and its entry points. Thereafter, as the tool manager receives messages from tools and/or the user interface, it sends messages only to the appropriate tools. The software which includes the tools are stored in a nested class/subclass arrangement such that software components which are common to several tools are stored once as a separate tool. <IMAGE></p> |
