## 4 Platform Design and Development
### Interface Design and Application
#### 4.4.3 Platform Usage Evaluation  
This study developed a platform to integrate historical buildings and 3D-GIS data to improve the interactivity and visibility of digital historical buildings. In order to improve the platform, user interviews were conducted to understand whether the development of the platform would be helpful for architects, GIS users, and platform developers in the field of cultural heritage conservation. Figure 17: iSpace-Urban Simulation and Cloud Computing Laboratory of Feng Chia University. Figure 18: iSpace achievement exhibition of the Urban Planning and Spatial Information Department of Feng Chia University. In response to the research questions raised in this study: it is not easy to integrate a single historical building with an old city block model, and the existing information model of the old city is insufficient in interactivity and visibility. The respondents in this study are architects, GIS users, and developers, with three respondents from each background, respectively. Three architects with experience in the field of cultural heritage conservation were selected, and this study did not subdivide GIS user respondents. The selected developer respondents had experience in platform development and game development, or interactive program writing using programming languages JavaScript, Python, or C#. All the respondents have computer application experience. The Unity3D game engine is a cross-platform system, which avoids the incompatibility problem of different users using different computer systems. Since the time and location of the respondents were different, this study set two interviewing methods: online visual communication and operation and interviews conducted in the iSpace-Urban Simulation and Cloud Computing Laboratory of Feng Chia University. After confirming the environment selected by the respondents, we provided a brief description of the platform, so that users could understand our purpose and the overall structure of the platform, and then, asked each user to operate the platform results in the form of execution files. In order to more clearly understand what is necessary for experts in different fields, and what they expect to present, users raised questions and gave comments after the operation. The content of the questionnaire is divided into three parts: (1) basic data, including personal background and the computer application experience of respondents; (2) according to [PERSON]'s (1995) usability heuristics for user interface design, this study presented 10 common questions to all the respondents, and asked them to make objective choices in a five-equidistance manner; (3) three questions were presented regarding the opinions of the respondents from different backgrounds after using the platform. At present, we have completed the link to the SketchUp solid model and 3D-GIS attribute data table through script writing, and designed the basic instructions commonly used by architects and GIS users, so that users in these two fields can use the models and data. The users indicated that they are highly impressed by the platform's purpose, the integration of historical building information models, and the ability for professionals to automatically visualize all the information they require in a Unity scene. This study also successfully integrated the GIS database and 3D SketchUp model of old city blocks, and used Unity to complete the visualization of the information model, thus, reducing the time cost for browsing drawings. Moreover, the simulated and highly spatial experience can also improve the spatial perception of users. This platform design conforms to the workflow of professionals in the field of cultural heritage conservation. In terms of interactivity, game development is mainly based on Unity. This study invited professionals to control the keyboard and mouse to guide the movement direction of the perspective; therefore, this is also an intuitive way for professionals to gain computer application experience.