## 3 Research Topic and Purposes
### Study Subject and Objective  
In summary, this study imported the BIM model of semantically rich buildings with wooden frames into a game engine for development and research of its interactive environment and takes historic scenes in Tainan as the research field, which aims to solve the problem of the insufficient interaction and communication of the historical building model, assist participants in communication and cooperation, ensure the accuracy of information during restoration, enhance management ability and restoration quality, reduce errors and communication difficulties through the design of an intuitive operational interface, and further develop the interactive function of the application.  
This study used the BIM model for historic buildings with wooden frames, which was built and completed by our team during the initial study of Huji Palace in Tainan [10, 11, 12], and relevant restoration and case diagnosis information were added into the model components. Parameters provided include the deterioration of component parts, the restoration method, restoration time, intervention level, restorers, and other non-geometric information.  
This study focused on how to expand the development and application of interactive ability within the parameters of existing BIM models of historic buildings. While this study does not discuss the modeling process, the detailed contents, or the back-end repair construction method, it places emphasis on the development of interactive scripts using existing information models to enhance the ability of information amplification and interaction.  
This study aims to develop a visual interactive operation and control environment that can promote the management capability for historic buildings and cultural heritage sites by using game technology to assist the integration of heterogeneous information in a historic scene, conduct practical research of the user interactive interface design, and enhance the visibility and interactivity of the BIM model of historic buildings. In addition to assisting communication and ensuring the integrity of transferred information, this visual interactive operation and control environment can also be used to optimize restoration at the construction site and to strengthen the application of historic building information modeling.  
The tasks expected to be completed under this study are as follows:  
1. Simplify visual operation: The user is provided with the functions of simple navigation, information query, or integration of different model information in the environment; the user can read the component restoration information by clicking and removing any inconsistent judgments, as caused by the complexity of the component information. Visibility and future applications may be enhanced through an intuitive presentation of visual information.
2. Enhance interactive communication: Animation is provided for the disassembly and composition of historic building components. Animation of disassembly with easily understood operation orders is made based on the consensus record of the architect and the survey staff of the research unit to assist participants in communication and use at the restoration site.
3. Overlay automatic information bi-directionally: the bi-directional information transmission function is provided through the plug-in application interface design, to ensure that model information can be accurately transmitted between building information modeling software (Revit) and the game integration platform (Unity). The restoration information of historic buildings is accumulated in the restoration record over time, which makes the integration process more logical and easier to operate, and the restoration information of different components during different periods can be read through selection by clicking.