Development of Front End Processor That Provides Midair Sketch Recognition Service for 3D CAD Applications

当本研究开始时，我们已经建立了一个利用虚拟现实(VR)环境的基于手绘草图的建模接口Blue Grotto。本研究的目的是建立一种将Blue Grotto作为字体端处理器(EP)的机制。通过研究，我们实现了为三维CAD应用程序提供空中草图识别服务的Blue Grotto FEP，并验证了该系统与现有CAD系统的结合，可以很好地应用于实际的基于草图的CAD应用程序。第三步，对蓝窟的可视化反馈系统进行了改造，提高了界面的可用性；第四步，利用C++和OpenGL实现了新的用户界面和通讯协议，并将其具体化；第五步，在通用的通讯协议的基础上，实现了两种实用的CAD系统(AUTOCAD和Shade)的接口模块；第六步，通过实验验证，所提出的通用通讯机制使得蓝窟与FEP在不同的实际CAD应用程序中都能协同工作结果表明，蓝窟FEP与实际CAD应用程序的结合可以作为基于草图的实用CAD系统，用户可以在蓝窟FEP的草图操作和实际CAD系统的命令操作之间自由切换。

When this research started, we had already established a freehand sketch-based modeling interface Blue Grotto that utilizes a virtual reality (VR) environment The aim of this research is to establish a mechanism that makes Blue Grotto serve as a font end processor (EP). As a result of the research, we realized Blue Grotto FEP that provides midair sketch recognition service for 3D CAD applications, and we confirmed that the combinations of Blue Grotto FEP and existing CAD, systems work well as practical sketch--based CAD applications.Step 1We introduced a skinning operation into Blue Grotto and established a new user interface with which a user can input multiple profiles by freehand drawing.Step 2We designed a versatile communication protocol between Blur Grotto and practical CAD applications. Then, we confirmed that the protocol realizes an automatic synchronizing mechanism in the combinations of Blue Grotto and the CAD applications.Step 3We reconstructed visual feedback systems of Blue Grotto and improved the usability of the interface.Step 4We implemented the new user interface and the communication protocol by using C++ and OpenGL and materialized Blue Grotto FEP.Step 5We materialized interface modules for two kinds of practical CAD systems (which are AutoCAD and Shade) based on the versatile communication protocol.Step 6Through some experimental trials, we confirmed that the proposed versatile communication mechanism made identical Blue Grotto FEP work in cooperation with different practical CAD applications.Step 7Through some practical drawing experiments, we showed that the combinations of Blue Grotto FEP and practical CAD applications can work as practical sketch based CAD systems, with which a user can freely switch between sketch operations of Blue Grotto FEP and command operations of the practical CAD systems.