On the Performance of Distributed Rendering System for 3DWebGIS Application on Ultra-High-Resolution Display

While the amount of data to be displayed on GIS continues to glow, WebGIS faces challenges in handling large datasets due to the heap memory limitations of web browsers. Meanwhile, the resolution of desktop displays is reaching its limit, making it challenging to display ultra-high-resolution content on the desktop, so using a Tiled Display Wall (TDW) offers a more feasible solution. In this context, we introduce ChOWDER, an open-source software that enables the distributed rendering of various contents, including 3DWebGIS on a TDW. It provides a detailed explanation of its distributed rendering functionality, utilizing iTowns, an open-source GIS platform, and Three.js, a JavaScript library for 3D graphics in a web browser using WebGL. As a practical example, using an ultra-high-resolution TDW system running ChOWDER, we will show how to display 3D WebGIS distributed rendering on a TDW with a horizontal resolution of 20K, composed of fifteen 4K displays and 15 PCs. Furthermore, we conducted experiments of distributed rendering of large-scale geographic information, including 3DTiles city building data on multiple displays, and confirmed that memory consumption was effectively distributed. ChOWDER is a middleware that can build ultra-high-resolution displays without special hardware. It can display not only 3DWebGIS distributed rendering but also various content simultaneously and in a bird's-eye view on ultra-high-resolution displays, making it applicable to applications such as wide-area GIS display and simultaneous display of a wide variety of data that cannot be overlaid on GIS.