# Connecting the Elderly Using VR: A Novel Art-Driven Methodology
## 3 Materials and Methods
### Methods and Tools
#### 3.4.4 VR Tool  
Unity ([[https://unity.com/](https://unity.com/)]([https://unity.com/](https://unity.com/)), accessed on 28 February 2024) was used to create the VR social platform and GRPC was used for communication. Before importing the 3D model into the VR Tool, an optimization procedure was followed because the obtained 3D mesh models from the 3D reconstruction techniques employed were often too complicated and complex to be handled directly in real-time VR applications. They consisted of millions of triangles and multiple texture files were assigned to the geometry to depict all the visual details. To overcome this, a typical workflow from the Computer Graphics Community is adopted, which includes:  
Figure 5: Initial 3D mesh model (**a**). Final rendered 3D CAD Model (**b**).  
1. Mesh simplification.
2. Physically Based Rendering (PBR) Texture Map Baking.
3. Level-Of-Detail (LOD) generation.  
To streamline the geometry of the reconstructed 3D mesh models, we utilized the \"Instant Meshes\" tool [57]. This tool employed a local-based approach to re-mesh the original 3D surface into an isotropic triangular or quad mesh. This approach optimized both edge orientations and vertex positions in the resulting mesh. The initial step involved computing an orientation field, defining the directions to which the edges of the simplified mesh should align. The subsequent step computed a local UV parameterization, where the gradient aligned with the orientation field and exhibited discontinuity over edges. Ultimately, a 3D triangular or quad mesh was generated from these two fields. This process resulted in a simplified version of the original 3D mesh model, comprising a reduced number of triangles. This is usually referred to as a \"low-poly\" model.  
Briefly, the architecture of the VR tool can be described by three main components:  
1. The VR headsets: These headsets support the software to view and interact inside a virtual environment.
2. The VR meeting room server: this server is responsible for creating a collaborative environment for the users using the VR headsets and populating it with the user's personal digital artifacts.
3. The database: the database houses the functionality to allow user authentication as well as the personal digital artifacts of the users.  
The collaborative VR application was designed for multiple users to immerse themselves into a single VR environment and collaborate as well as view and manipulate objects inside the VR environment. The VR application was built using Steam VR to provide maximum compatibility with VR devices. The application allowed users to log into their user accounts and create meeting rooms, which other users could join. The users were able to join the session in VR as well as on desktops. In fact, the first two prototypes of the study were evaluated as desktop versions, while the last prototype was evaluated using a VR headset. A \"VR Ready\" laptop successfully operated the tool. Furthermore, the VR meeting room server had the capacity to support a multiplayer server, enabling concurrent interaction among multiple users. This server was responsible for populating the VR environment with digital artifacts sourced from a backend database. The VR meeting room server was hosted on a dedicated server, facilitating the construction and execution of the service.