Democratizing BIM Data Access in Digital Twins Through OGC I3S 3D Streaming Standard

Geospatial users have long been constructing immersive 3D environments for diverse applications such as urban planning, environmental and geological studies, 3D analysis, and more recently, by replicating the physical world as a digital twin. In this pico presentation, we aim to illustrate the dynamic evolution of Indexed 3D Scene Layers (I3S), an OGC Community Standard designed for an efficient streaming and storage of substantial geospatial content. I3S has rapidly adapted to encompass new use cases and techniques, pushing the boundaries of geospatial visualization and analysis. I3S facilitates the efficient transmission of diverse 3D geospatial data types, ranging from discrete 3D objects with attributes and integrated surface meshes to extensive point cloud data covering expansive geographic regions. Moreover, it excels in streaming highly detailed Building Information Model (BIM) content to web browsers, mobile applications, and desktop platforms. The most recent enhancement to OGC's I3S streaming standard, Building Scene Layer (BSL), introduces a sophisticated framework for effective tiling of massive BIM content. BSL leverages Bounding Volume Hierarchy (BVH) and geometric error driven selection and display criteria, incorporates attribute-driven filtering, and employs various graphics optimizations. These advancements collectively enable the seamless streaming of otherwise voluminous Building Information Model (BIM) 3D assets. During this session, we will spotlight the practical implementation of I3S BSL across diverse ecosystems, including loaders.gl and CesiumJS. This flexibility empowers users to select their preferred front-end application based on specific requirements and preferences.