Cesium for Omniverse v0.25.0

Cesium for Unity Samples v1.16.2

CesiumJS 1.131

CesiumJS

Editor's note: Cesium is committed to open source, open standards, and rapid innovation. We power training, planning, operations, and analysis across the US Department of Defense and Intelligence Community. We're proud to have collaborated with NUWC Division Newport and NSWC Carderock Division on this article about the impact of OTAs. Read the PDF here.

In March 2025, Defense Secretary Pete Hegseth issued the memo “Directing Modern Software Acquisition to Maximize Lethality,” mandating the use of the Software Acquisition Pathway for all Department of Defense (DOD) software development procurements. This memo also instructs DOD components to prioritize Other Transaction Authority agreements (OTAs) and Commercial Solutions Openings (CSOs) as the preferred methods for acquiring software capabilities. 

OTAs were created in 1958 to give DOD flexibility to incorporate business practices that reflect commercial industry standards and best practices into how it awards contracts. DOD historically employed OTAs in conducting research and development; in 2016, the National Defense Authorization Act expanded the use of OTAs to include prototype and production. This expansion provided the warfare centers with another alternative to a Federal Acquisition Regulation (FAR)-based procurement contract. 

NAVSEA’s warfare centers have been doing business this way for years. 

In 2016, the Undersea Technology Innovation Consortium (UTIC) was stood up as a non-profit research organization comprised of small and large technology companies, academia, and nonprofits who are developing undersea technologies and addressing defense and security challenges.  

By 2018, UTIC, represented by management firm Advanced Technology International, and NUWC Newport Division signed a three-year OTA contract (renewable for up to 10 years) to explore Undersea Technology Innovation in a broad range of undersea and maritime prototyping activities. NUWC Newport Division’s contracting professionals began exploring how to use OTA to deliver prototypes to the submarine Fleet faster and soon released its first Call for Topics under the OTA—the first warfare center to pursue this option.

Their success led to collaboration with other warfare centers including the Naval Surface Warfare Center (NSWC) Carderock Division via Dave Sracic, Distinguished Software Engineer for Fleet Signatures Systems.  

Sracic needed a solution that would let him approve software development without micromanaging it. In 2019, Sracic awarded two agreements utilizing NUWC Newport Division’s UTIC OTA, one of which went to Analytical Graphics Inc., whose subcontractor was Cesium.  

Cesium specializes in 3D geospatial technology, particularly for visualization and analysis. The company is considered a “non-traditional” government partner, which was a major aspect of the success of the collaboration. 

As part of the OTA prototype agreement, Cesium provided a platform for building 3D geospatial applications, including CesiumJS, an open-source library for 3D visualization in web browsers designed for robust interoperability and scaling for massive datasets. Cesium works to advance the geospatial ecosystem and open source, open standards, data sharing, and interoperability.  

In May 2024, NSWC Carderock awarded $2.2 million to Cesium through the OTA.  

Stills from Cesium’s bathymetry data set.

“UTIC had already proven to be effective for my team and our small initial toe-in-the-water approach had been highly successful. Given the choice between working with NUWC Newport to put together a new Request for Prototyping versus pursuing a traditional FAR-based path, it wasn’t much of a choice at all—I’ll take six weeks over 18 months any day,” said Sracic. 

Trent Tinker, director of Cesium’s federal business development, said, “From Cesium’s perspective, the OTA streamlined administrative processes and allowed for a direct line of communication with Navy customers. The OTA got us a step closer to the end users, and ensuring their data supports better, faster decisions is something that we’re really excited about.” 

According to Sracic, “Open source software is a building block of nearly every DOD system, and at some level, virtually all of the world’s most complex software systems. Our key challenge in building Navy combat systems is in using open-source software without finding ourselves trapped when it evolves faster than we do. Our thought was we’re using this open source CesiumJS and it does 80 percent of what we want, so let’s pay the experts who built it to make it do more.” 

As Sracic explained, “We got those changes back into CesiumJS, upstream, open source version, which means we do not have to keep a Navy fork of that software. The open source community maintains those specific changes. We care deeply about those features and use them heavily. Now that they’re part of the master branch, with test cases, we have reasonable confidence they won’t die, and we don’t pay some kind of sustainment fee. This is what the DOD policy aspires to—the government contributing back to open source.” 

“The OTA also enables Cesium to work with warfare centers on the open source position of their challenges,” said Tinker. “While some of the development stays with the government, other roadmap-aligned services go to the open source baseline and benefit everyone.” 

“Public-private partnerships between the Navy and UTIC members enable the Navy to create new paths to acquire and improve technological capabilities aboard its fleet, focusing on critical missions rather than the building blocks of visualization. Dave Sracic was proactive and flexible, and our terms were Firm Fixed Price, pairing our risk tolerance and desire to do meaningful work as a technology growth company,” said Patrick Cozzi, Cesium founder and Bentley Systems chief platform officer. 

“This is quantifiable value and return on investment, and sufficient to justify follow-on efforts to integrate capability into a combat system, which is a win for Navy in that it’s already risk-reduced and well understood,” explained Sracic. “And it’s a win for industry, which can do that work through non-competitive follow-on to the OTA.”

In June, we announced a geospatially accurate 3D Globe in QGIS supported by a Cesium Ecosystem Grant, shared our roadmap to seek your guidance as we bring iTwin digital twin capabilities to Cesium, enabled draping imagery layers on 3D Tiles in CesiumJS, and welcomed the community to Philadelphia for the first Cesium Developer Conference. 

The iconic red PSFS letters on top of the Loews Philadelphia Hotel went blue one night and green the next during the 2025 Cesium Developer Conference.

We made improvements across Cesium this month. To get notifications about our monthly releases, you can subscribe to the Cesium release roundup thread on our community forum.

CesiumJS 1.131 is now available. Highlights of the release include:

Added experimental support for loading 3D Tiles with Gaussian splats encoded with SPZ compression using the draft glTF extension. KHR_spz_gaussian_splats_compression in CesiumJS 1.130.1 #12582 

Added HeightReference to Cesium3DTileset.ConstructorOptions to allow clamping point features in 3D Tile vector data to terrain or 3D Tiles. #11710 

Added the ability to pass OffscreenCanvas & ImageBitmap directly to Material uniforms. #12558 

Fixed raymarching step size for cylindrical voxels. #12681 

Fixes handling of tileset modelMatrix changes for translations and rotations in GaussianSplatPrimitive. #12706 

Gaussian splats (left) compared to 3D Tiles Mesh (right) in CesiumJS. Try the Sandcastle.

Cesium for Unreal v2.17.0 is now available. This is the last release of Cesium for Unreal that will support Unreal Engine v5.3. Future versions will require Unreal Engine v5.4+.

Added a C++ and Blueprint API for loading and accessing GeoJSON data. 

Feature IDs that are encoded by UCesiumFeaturesMetadataComponent will now use a default null feature ID of -1 instead of 0. 

Materials generated by UCesiumFeaturesMetadataComponent now always check for null feature IDs, assuming a default value of –1. 

Check the Cesium for Unreal release and the Cesium for Unreal Samples release for the full list of updates.

Download the Cesium for Unreal plugin from Epic Marketplace

Landmarks in an area in Singapore, parsed from GeoJSON and visualized in Cesium for Unreal. Sourced from iTwin Reality Feature Service (support in progress).

Cesium for Unity v1.16.2 is now available. Highlights of this release include:

Fixed broken support for TRIANGLE_FAN primitives in tile meshes. 

Fixed an editor crash that occurred when any scale component on Cesium3DTileset was set to zero. 

Fixed a bug where CameraFlyToController, after the user interrupted a flight, would jump to the middle of the flight path immediately upon starting the next flight. 

Check the Cesium for Unity changelog for the full list of updates, and follow our Cesium for Unity tutorials to get started. 

Mesh reconstruction from photos is available as a technical preview. Upload geolocated photos and select the Photos (for 3D reconstruction) option. Read more. 

Added the ability to perform analysis on point clouds to produce classified point clouds. Try it with the Analyze button on the asset details panel. Read more. 

Gaussian splats is available as a technical preview. Upload a PLY file and enable the Gaussian splats toggle. Read more. 

Fixed a rare issue with tile subdivision that could cause unnecessarily deep tileset trees. 

Fixed an issue causing a crash for some models with no materials. 

Set the mipmap generation option to be off by default. 

Check the changelogs for the full list of updates for Cesium ion SaaS and Cesium ion Self-Hosted.

Cesium ion “city detector” analysis tool as seen in Cesium Stories.

To promote the adoption of a structural health monitoring system, earthquake engineering researcher Kensaku Kaneko is pioneering a new approach—visualizing building safety through 3D web GIS with CesiumJS. 

Hobu developed its browser-based Eptium viewer using CesiumJS to enable users to visualize and interact with massive point clouds and raster data. 

Nippon Koei uses Cesium ion and Cesium for Unreal, significantly streamlining the acquisition and processing of accurate geospatial context for a design area. 

HNTB’s Immersive Media Solutions team uses Cesium ion, Cesium for Unreal, Cesium for Unity, and Google Photorealistic 3D Tiles to help community stakeholders better understand proposed infrastructure projects and engage meaningfully in the approval process. 

With the release of CesiumJS 1.130, users can drape imagery layers on 3D Tiles, allowing developers more freedom to combine geospatial data from different sources. Reality meshes, CAD/BIM data, and point clouds can be uploaded to Cesium ion and converted into 3D Tiles for efficient streaming and visualization. Now, imagery data like Bing Maps imagery or OpenStreetMap imagery can be layered on top, creating more powerful 3D geospatial applications. This addition addresses a long-standing community request and supports a wide range of use cases.

An example of draping imagery on 3D Tiles: Google Photorealistic 3D Tiles with Google Roadmap tiles overlay providing street and label data.

Use case 1: Orthophotography over reality meshes 

Existing reality mesh datasets can be augmented with high-quality, curated orthophotography imagery data. In this example, Bing Maps Aerial imagery is added to a 3D Tiles point cloud dataset without color data.

Use case 2: Sensor data layers over 3D Tiles 

The results of sensor coverage data, satellite imagery, or AI-based classification can be mapped on 3D Tiles to visualize the results of different analysis workflows. Here is an example where the user can select different imagery layers provided by NASA Earth Data, to overlay information like the biomass or population density over Photorealistic 3D Tiles.  

An example of draping imagery on 3D Tiles: Google Photorealistic 3D Tiles with information about the population density, provided by NASA Earth Data.

Use case 3: Adding contextual information over 3D Tiles 

Imagery can also be used as overlays to provide additional geospatial context about roads, buildings, or other points of interest. For example, imagery data that provides geospatial information can be draped over existing 3D Tiles datasets. 

An example of draping imagery on 3D Tiles: Bing Maps Labels draped over a tileset that was loaded from iTwin reality data.

This new feature is similar to the existing functionality of draping 3D Tiles on terrain data, so users can seamlessly leverage it with little effort. This simple example shows how to drape imagery data on 3D Tiles. The Cesium3DTileset class now offers a set of imagery layers, and these can be used exactly the same way as imagery layers for terrain in CesiumJS. This means adding the imagery to the to the tileset can be done with a single line of code: 

```js
tileset.imageryLayers.addImageryProvider( 

  await Cesium.createWorldImageryAsync({ 

    style: Cesium.IonWorldImageryStyle.AERIAL, 

  }) 

); 

The imagery layers that are added to a tileset are added as an ImageryLayer object. This object has several properties that affect the visual appearance of the imagery data as it is draped on the 3D Tiles data. Users can modify the alpha value (opacity), brightness, or saturation. This sandcastle showcases the ability to modify properties in real time. 

The first release of draping imagery over 3D Tiles that is part of CesiumJS 1.130 includes functionality that serves most use cases. There are several possible extensions or functionalities that can be added based on community input—for example, user controls to align existing imagery data with the 3D Tiles or to "upsample" the 3D Tiles geometry with imagery resolution that is higher than the geometry with large geographics extent. 

We welcome feedback about the draping functionality and thoughts about further use cases that should be supported via this community thread. 

Draping Imagery over 3D Tiles in CesiumJS 

It’s been just over nine months since Cesium joined Bentley Systems. We’ve used that time to learn more about the technologies built by Bentley and opportunities to bring them to the community. As we look forward to the first Cesium Developer Conference, we are sharing our roadmap to seek your guidance as we bring iTwin digital twin capabilities to Cesium. 

Our mission is to empower the community to build 3D geospatial experiences at the convergence of the built and natural environment. 3D Tiles has seen tremendous adoption, including by Google, Esri, Ansys, FOX Sports, The Weather Company, GE Aerospace, MathWorks, CAE, Trimble, and DroneDeploy, to name a few. Cesium ion receives more than 300 million monthly requests from over 30,000 monthly active users. Cesium’s runtime engines—CesiumJS, Cesium for Unreal, Cesium for Unity, and Cesium for Omniverse—continue to enable rapid development of new 3D geospatial applications by an ever-growing community as we continue to deeply invest in open source. There is bottomless demand for more curated data, high-performance tiling pipelines that support more inputs, tools for more efficient end-to-end workflows, and improved end-to-end performance. 

As part of Bentley, we have the opportunity to radically empower and expand the 3D geospatial community by leveraging best-in-class technology from Bentley to benefit all the broader ecosystem. Cesium has always been guided by community input, and we’d like your feedback on these themes on our roadmap: 

Integrate reality modeling and AI-powered analysis services with Cesium ion; 

Expose iTwin Platform APIs and services through Cesium; 

Introduce composable tiling pipelines to optimize your data as 3D Tiles; 

Advance Cesium runtime engines to capitalize on new 3D Tiles extensions and platform integrations; 

Provide reusable and configurable user experience tools and widgets; and 

Improve learning material and ongoing maintenance. 

3D Tiles is the core of the platform. It is the thread that weaves through the entire platform and community to be a cohesive end-to-end workflow, empowering developers to build extraordinary applications. We’re adding several capabilities to 3D Tiles that have been long requested by the community. 

Users across industries are capturing the environment at ever greater resolutions, more frequently, and with more types of devices. This exponential scaling creates opportunities to extend the 3D Tiles specification for more efficient storage, streaming, visualization, and analysis of 3D geospatial data that is spatially coherent and updated over time. 

Time-dynamic 3D Tiles is an extension that efficiently introduces the time dimension to 3D Tiles. Using time-dynamic tiles allows a single tileset to be updated over time, with each new capture updating only affected tiles. No longer will an entirely new tileset need to be created for each update; a single tileset can be updated incrementally, preserving a history of changes and allowing for more efficient and faster generation of updated tiles.  These can be used for analytical workflows, too, such as changeset analysis over time and comparing tilesets over time to design models. Visit the GitHub issue to share your input. 

Time-dynamic tiles allow a single tileset to be updated over time, with each new capture updating only affected tiles.

We’re also exploring connecting Bentley’s SYNCHRO 4D Schedule API to generate time-dynamic 3D tilesets. The SYNCHRO 4D Schedule API allows time-dynamic project data to be accessed and used over the web. This connection will converge time-dynamic geometry with business intelligence. 

Volumetric data has become an important way to visualize real-world content in numerous domains where continuous representation of data is required, such as geology, oceanography, and climate science. The 3D Tiles specification is intentionally flexible in supporting a variety of geometry types to best represent massive heterogenous data. By using voxels (volumetric elements) as a 3D payload with 3D Tiles, you will be able to build applications with global-scale volumetric data. We’re working on ellipsoidal, cuboid, and cylindrical voxels as a starting point in the 3D Tiles specification with glTF as the voxel payload. This will enable opportunities for volumetric data for subsurface, land, air, and space. Take a look at the draft Voxels extension. 

Water temperatures in the Gulf of Mexico represented using Voxels in CesiumJS.

One of the most popular topics recently in computer graphics is 3D Gaussian splats. High-resolution reality meshes and point clouds are fantastic for digitalizing our natural environment, but they fall short in capturing a few types of information, such as cables, trees, bars, telecom towers, etc. 3D Gaussian splats have proven to be a fantastic solution for preserving visual detail while maintaining very high fidelity. 

We are excited to add 3D Gaussian splats as a payload type in 3D Tiles, including adding the technology behind iTwin Capture to Cesium ion to enable modeling and tiling of 3D Gaussian splats. We’re collaborating with the glTF community and introducing a 3D Gaussian splat extension for glTF.  

Comparing 3D Gaussian splats using 3D Tiles (left) with Reality Meshes (right), with particular significance to the thin-and-long geometry such as wires, dishes, poles, and scaffolding.

Bentley Systems was an early adopter of 3D Tiles and has developed extensions to enhance the 3D visualization capabilities required for detailed infrastructure models. Cesium joining Bentley presents the opportunity to converge these extensions and runtime implementations to make them accessible to the entire community.  We are working on adding edges and wireframes, line rendering and materials (width, patterns, colors), customizable point sizes, billboards for annotations, and more. 

A 3D Tileset visualized in iTwin.js with glTF EXT_mesh_primitive_edge_visibility extension for highlighting edges.

Implicit surfaces enable representations of parametric shapes—like pipes, columns, beams, boxes, spheres, and cylinders—when used with other implicit surfaces for the creation of complex geometries that are hard to represent with triangle meshes. The benefits of this are in the storage and accuracy for analytics. Because the surfaces are not approximated as triangles meshes, the surfaces are rendered without geometric error. We are building on the glTF implicit shapes extension, introduced by Microsoft. 

The 3D Tiles specification supports rich metadata that adds properties and classifications to geometry. The metadata specification is written with the intent to add semantics at different granularities and for a variety of industries and use-cases. There is a need to define semantic vocabularies in the architecture, engineering, and construction (AEC) industry that also offer a taxonomy applicable to classes of objects. Capturing the meaning of these classes in a standard vocabulary enables downstream repurposing of this information in AI-driven data validation, data–interoperability, analytics, or interactivity. For example, downstream understanding that a class in a custom user-schema is modeling “doors” could be captured in terms of an applicable standard vocabulary—from IFC, Uniclass, or BIS—which other data consumers could operate on.  

The Base Infrastructure Schema (BIS) is a family of modular schemas that express taxonomy, data structure, and relationships for modeling federated data from infrastructure engineering. BIS schemas are organized into layers, most of them defining the rules and patterns considered as standard in the BIS ecosystem. The semantics embedded in standard BIS schemas have proven to be valuable in contexts beyond iModels.  

We’re working on a 3D Tiles extension for metadata semantics to cover classes, as well as ensuring encoding properly enables BIS and other similar semantic vocabularies.  

Integrate reality modeling and AI-powered analysis services with Cesium ion

One of the most exciting outcomes of Cesium joining Bentley is the opportunity to integrate reality modeling and AI-powered analysis services with Cesium ion. You have been vocal about wanting to be able to upload photos to generate 3D models, and we’re thrilled to be able to deliver on that by integrating the industry-leading technology used in iTwin Capture with Cesium ion. By using an integrated end-to-end pipeline from photos to 3D Tiles and from 3D Tiles to rendering and analytics, we aim to provide the best-in-class experience for using reality data in your 3D geospatial applications. With the advancements in 3D Gaussian splats, this will also support the pipeline to go from photos to 3D tilesets of splats. 

Adding Reality Modeling to Cesium ion enables users to create 3D Tiles from photos as input using the reality modeling technology used in iTwin Capture.

Reality analysis using AI feature detectors

Bentley has also built the technology to identify objects, regions of interest, or defects in reality data using AI. By integrating reality analysis into Cesium ion, we want to enable users to apply 3D segmentation and classification to reality. This analysis will be enabled in two forms: 

Embedded metadata in the 3D Tileset, allowing for runtime querying, styling, and filtering. 

Supplemental vector data as features extracted from the reality data, which can be used for overlays, annotations, and styling. 

We are adding vector data support in Cesium’s native plugins to enable all runtimes to use the results of the reality analysis. The result: real-world insights into reality data, supporting data-driven decisions. 

A 3D Tileset of a point cloud with embedded classification generated using AI-enabled reality analysis service.

For an initial release, we’ll enable analysis on reality meshes and point clouds, providing you with options through a growing list of curated analysis detectors. You will be able to analyze models already uploaded to ion, or generated with ion’s new reality modeling capabilities, creating an efficient, end-to-end workflow. The curated detectors include analysis for segmentation of trees, railway objects, and city elements, as well as others.  

In future releases, you can create your own custom detectors to run in ion. We are planning for 3D analysis of Gaussian splats, 2D segmentation of photo collections, and offering analysis in Cesium ion Self-Hosted.  

Expose iTwin Platform APIs and services through Cesium

iTwin Platform powers digital twin solutions that are used in AEC applications to design, build, and operate infrastructure around the world. By connecting iTwin and Cesium platforms, our goal is to provide a complete platform for digital twin experiences for the built and natural environment, with a strong commitment to open source, open standards, and open APIs. 

Exposing iTwin Platform APIs and services through Cesium channels will enable you to leverage capabilities like clash detection for design reviews; change elements to monitor design updates; perform analysis, such as carbon calculations; and apply AI-powered federated search to search and filter across 3D objects, engineering information, and business documents. Using iTwin Platform’s synchronization services, you will be able to bring in many more inputs for design models, which can then be added to Cesium apps as 3D Tiles. 

Clash detection and review shown in iTwin.js. 

Introduce composable tiling pipelines to optimize your data as 3D Tiles

Tiling pipelines to create 3D Tiles enable you to bring your own data into your 3D geospatial applications, a core requirement for most use cases. Over the years, Cesium has developed and introduced many tiling pipelines for different types of data: reality data, point clouds, design models, 3D buildings, terrain, imagery, and more. All of these tiling pipelines have their technological merits, but they are siloed based on the type of input data. Adding Bentley’s tiling pipelines for reality data and AEC design models results in even more tiling and optimization algorithms—that are also siloed. 

The vision for composable tiling pipelines is to have a unified, modularized, plugin-based pipeline that allows users to configure the stages for data conversion, tiling, and optimization. Example stages can include input file format conversions, coordinate system operations, mesh decimation, texture simplification, choice of tiling schemes, texture atlasing, mesh and texture compression, metadata processing, incremental updates, 3D Tiles-to-3D Tiles optimization, and output validation. The stages will be connected using a graph structure allowing the mix and match of stages, with a set of standard ready-to-use pipelines available to all of our users. 

Improvements to AEC-to-3D Tiles workflows

Community reception of Cesium’s Design Tiler and Cesium ion for Autodesk Revit Add-In has been overwhelmingly positive, with lots of input on more design applications and features to be supported. With additions from Bentley software, we aim to level up the workflows for AEC data in key areas: 

Support for other CAD formats to 3D Tiles, such as Navisworks, MicroStation, and SketchUp. 

Ability to do incremental near real-time tiling. As you are creating and updating your designs, we want to add the ability to tile only the changed elements, rather than the entire model. This will shorten the life cycle by having a ready-to-go 3D Tileset alongside your design models at all times. This will be complemented by lightweight apps to synchronize your designs into a geospatial experience. 

Enhancements to the LOD generation in the Design Tiler to better support even larger and high-detail projects. 

Specialized 3D Tiles selection algorithms using metadata-driven rendering, filtering, and search. 

Triangle mesh of an AEC model with 10 million triangles created in Autodesk Revit and visualized in CesiumJS using 3D Tiles.

If you’d like to see specific software or features supported, reach out to us on the community forum. 

Advance Cesium runtime engines to capitalize on new 3D Tiles extensions and product integrations

Cesium’s open source runtime engines—CesiumJS for the browser and plugins for Unreal Engine, Unity, and NVIDIA Omniverse—are the face of the platform as the software users experience and interact with the most. The roadmap for runtime engines will advance the convergence of built and natural environment, AEC and geospatial, and of iTwin Platform and Cesium, providing developers and users with extended capabilities. 

The biggest impact for runtime engines will be the implementation and deep integration of the aforementioned updates to the 3D Tiles specification including 3D Gaussian splats, voxels, time-dynamic 3D Tiles, geometry highlights, implicit surfaces, and more. The addition of these advancements in every runtime will be a giant leap forward for many industries and applications. 

With the aim to lower the barrier to entry for building applications that integrate iTwin Platform APIs and services, we’ll add developer APIs and user interfaces for easy integration with iTwins. This means you will be able to build 3D geospatial applications integrating engineering and business information from iTwin into Cesium applications, similar to services like Cesium ion. 

In addition to the cross-cutting updates we covered above, we’re also making engine-specific improvements: 

Add configurable preset camera options to allow other navigation types, such as first-person walkthroughs in indoor spaces, underground, and undersea, toward more immersive applications. 

Improve vector data visualization, including rendering improvements to lines rendering, billboards, and overall scalability of these systems. 

Support multiple viewports for different views in the same runtime with optimized streaming and selection algorithms. This benefits a broad spectrum of applications, including AEC, simulation, operational environments, infrastructure inspections, and many more. 

Develop a new Sandcastle to make onboarding, prototyping, and learning easier. 

Longer term, we’ll explore using WebGPU as a generational advancement in Graphics API. We’re also interested in unifying the 3D Tiles selection and traversal algorithms using Cesium Native via WebAssembly, creating a single reusable library for all Cesium runtimes, resulting in faster updates and efficiency across the board. As we explore these forward-looking upgrades, we’ll continue to invest in the broad compatibility of CesiumJS across browsers, platforms, and devices. 

3D reality mesh with AI-powered reality analysis-generated features visualized in CesiumJS.

Cesium Native, Cesium for Unreal, Cesium for Unity, and Cesium for Omniverse

Introduce a decoration system for runtime enrichment of 3D geospatial scenes with 3D assets. The system empowers creators building rich 3D geospatial environments to add capabilities like runtime editing of 3D Tiles materials, adding 3D objects to the environment, such as trees, cars, and city furniture, and synchronizing with the cloud. This will allow you to dynamically augment captured reality data with high-fidelity models at runtime, such as from Unreal Engine’s Fab marketplace. 

Performance is an evergreen pursuit with all runtime engines, but especially so with the native runtimes, where the benchmarks are real-time games. We’ll continue to invest in performance optimizations that reduce latency, improve game thread usage, lower memory overhead, and overall create a seamless experience. 

With the introduction of time-dynamic 3D Tiles for use cases like project scheduling and simulation, we’ll also add capabilities that take advantage of game engine features like animations, physics, controllers, and more. This will help create a full digital twin of not just the environment but also the vehicles, heavy machinery, traffic simulation, equipment, tools, and other IoT devices.  

iModel of a soccer stadium in Singapore visualized in Cesium for Unreal as 3D Tiles using iTwin’s Mesh Export service.

Building geospatial applications needs data, which is usually fragmented, unprocessed, and not streaming or runtime ready. We aim to lower the barrier to entry by making global datasets accessible, especially where data may be difficult to collect. Toward that goal, we are: 

Upgrading Cesium World Terrain—adding new and higher resolution content across the world. 

Adding high-resolution insets on the Moon. 

Introducing a planetary dataset for Mars. 

Providing analytically derived datasets, such as land-use classification. 

In addition to curated data, we’ll continue to invest in collaborations with Microsoft, Google, and other ecosystem partners to add more datasets for the community via Cesium ion. 

Provide reusable and configurable user experience tools and widgets

In line with our cross-cutting product and open standards investments for more powerful 3D geospatial applications, we will publish a library of reusable and configurable user experience tools and widgets that leverage existing libraries used by iTwin. These will allow you to build even more powerful applications faster and make them configurable, so that each application can refine the widgets and workflows. 

A representative mockup of the new Sandcastle built using the Strata library for components.

Improve learning material and ongoing maintenance

Authentic education is part of Cesium’s mission. Over the years, we have written many tutorials, presented dozens of conference talks, provided hundreds of code examples in Sandcastle, and joined the community in answering over 18,000 topics on the forum, and now we are on the cusp of hosting our first developer conference. 

As the field of 3D geospatial continues to advance, there is also an increase in demand for accessible, up-to-date learning content. To serve our community, we plan to roll out tutorials on reality modeling, AI feature detectors, 3D Gaussian splats, configuring runtime engines, performance optimization, and using and extending metadata in 3D Tiles. We are also creating a new Sandcastle for the example code repository that has improved modern developer tools like IntelliSense, code validation, and better search and organization so you can easily find what you are looking for. 

Finally, ongoing maintenance should not be underrated. It is part of our pact with the community, the heartbeat of the platform, and it generates fresh ideas for our collective roadmap. Pull requests need to be reviewed. Bugs (or fixes!) in browsers or game engines need corresponding updates. Better workflows for engaging with and creating transparency for the community on GitHub and the community forum need to be explored, especially as we introduce iTwin Platform and iTwin Capture. We will increase our essential activity here. 

Our aim is to strengthen and expand the open platform to serve the software developer community building digital twins for the built and natural environment. To do this, we will explore avenues to bring Bentley's capabilities to you, along with increasing our investments in R&D, the open-source community, and industry collaborations. 

Throughout Cesium’s history, the community has guided us, and we want to continue to hear from you. What are the products, features, integrations, and bug fixes that you would like to see?  Are there capabilities within iTwin or other Bentley products we should prioritize for integration? Are there open standards we should integrate or partnerships we should invest in? 

We want to hear all requests—big or small—for what you would like to see from Cesium and for the ecosystem in general. Share your thoughts with us on the community forum.

Cesium Roadmap for Bridging the Built and Natural Environment 

Hobu, Inc., with its deep roots in open-source geospatial, has led the contributions of standards and tools such as PROJJSON, ASPRS LAS, Cloud Optimized Point Cloud (COPC), and the Point Data Abstraction Library (PDAL). To enable Hobu’s users to visualize and interact with massive point clouds and raster data, the company developed its browser-based Eptium viewer using CesiumJS.

Eptium builds upon CesiumJS to allow users to directly visualize and interact with COPC and Cloud Optimized GeoTIFF in the browser in 3D. Supporting these archive and transmission formats reduces data duplication and conveniently enables visualization of commonly available cloud content. Eptium makes city- or country-scale point cloud datasets accessible for visualization and analysis on the web, especially for disadvantaged users. Streamlined access to massive cloud-based datasets enables interactivity and understanding for a broad audience, including those in the field or students and professionals using devices without high-end graphics capabilities.

Eptium users can perform multipoint observer line-of-sight (LOS) analysis, generate viewsheds, and export GeoTIFF or SVG images directly from the browser without the need for specialized desktop software. They are able to collaborate by saving and sharing application view state as links. Customers use Eptium as a complete web application, build with it as a JavaScript developer bundle, or directly use it for free by visiting eptium.com and pointing at their own data.

Point cloud and viewshed of Montreal, Canada, in Eptium. Courtesy Hobu.

Distribution of point clouds as COPC eliminates the need for extensive preprocessing or local storage of large files. Eptium consumes COPC data on the fly, converting it into 3D Tiles in-browser for efficient streaming. Eptium optionally uses Cesium World Terrain via Cesium ion and Bing Maps Aerial imagery for additional geospatial context. For a comprehensive picture of areas of interest, this data is fused in CesiumJS, which was built for interactive web apps and scaling for massive datasets.

Eptium, COPC, and CesiumJS also power the moonlidar.com application that Hobu's Connor Manning created in support of NASA’s recomputation of the Moon’s elevation.

The Hobu team uses CesiumJS for moonlidar.com. Courtesy Hobu.

By combining Hobu's expertise with CesiumJS, the Hobu team empowers geospatial users by making complex 3D data accessible and actionable.

Learn to build your own CesiumJS app for 3D geospatial visualization and analysis on the web by following our tutorials.

Hobu's Eptium Visualizes Country-Scale Point Clouds with CesiumJS

今回ご紹介するのは、大阪公立大学の金子健作博士による挑戦です。金子氏は建築物の耐震工学を専門とし、最近では、AIを活用した構造ヘルスモニタリング (SHM) を研究されています。SHMとは建物内に加速度センサを設置して、大きな地震の発生直後に建物の安全性を自動的に判定する技術です。このSHMの新たな展開に関して、金子博士はこのSHMシステムの普及を進めるために、3DのWeb GISで建物の安全性を可視化する新たなアプローチに挑戦しています。

構造ヘルスモニタリング（SHM）に利用される加速度センサは、地震時の建物の揺れを記録します。これらのセンサは建物内に設置され、クラウドサーバーにデータを自動的にアップロードする機能もあります。(画像提供：金子 健作 博士）

金子氏がCesiumJSに興味を持ったきっかけは、2021年に国土交通省のProject PLATEAUに関する記事を読んだことでした。Project PLATEAUは、日本全国の3D都市モデルを整備し、オープンデータとして公開する国家プロジェクトです。

「当時、私はGISを本格的に使ったことがありませんでした。しかし、PLATEAU ViewerでCesiumJSが使われていることを知り、試してみようと思いました。また、地球規模の数千kmから建物室内の数mまでスケール感を損なわずにシームレスに可視化できる点に強く惹かれました。」（金子博士）

最初は純粋な興味から始めましたが、CesiumJSの柔軟な3D可視化の可能性に魅了され、学びを深めていきました。2Dでは味わえない3Dならではのスケール感を実感し、オープンデータの活用とWebでの展開により、より多くの人々に役立つシステムを世に問うことが大きなモチベーションの一つとなりました。彼はCesiumJSで多数のエンティティを効率的にレンダリングし、地上構造物と地下構造物の両方を表示する方法を学ぶ中で、Cesium community forumなどのリソースを活用しました。

大阪市内で想定される津波浸水深と3D都市モデル、緊急避難場所の情報を重ね合わせてWeb上で表示した例。（画像提供：金子 健作 博士）

金子氏はAIによる都市スケールの広範囲な地震被害推定と構造ヘルスモニタリング（SHM） の統合を目指した先端的な研究に取り組んでおり、Cesiumはそれに役立てられています。将来的にSHMは、ドライブレコーダーのように多くの建物に導入されて一般市民に認知されことが期待されるなか、AIはSHMの普及を後押しすると金子氏は確信しています。研究過程で開発されたシステムは、「MeSM」と命名されています。MeSMという呼称は、Machine Learning-Enhanced Structural Health Monitoring（機械学習を活用した構造ヘルスモニタリング）プロジェクに由来しています。現在では、SHMの記録やAI機能を含む研究成果を省いた形で、市民が日常的に活用できるようにWebアプリケーションが一般公開され、防災講座や教育にも活用されています。

この研究プロジェクトは、三つのアプローチから構成されています。第一のアプローチは、日本の気象庁から得られる地震情報（震源位置、震源深さ、マグニチュードなど）を基に、3D都市モデルを活用して建物ごとの構造情報を考慮したうえで、事前学習したAIによって都市レベルでの地震被害を即時に推定するものです。この推定は、数十万棟規模あるいはそれ以上の面的な被害情報を含み、CesiumJSを用いて可視化されます。ただし、この手法には被害推定の不確かさが伴うという課題があります。第二のアプローチは、加速度センサを1台だけ設置した建物において、センサ情報と構造設計情報を組み合わせて被害推定を行うものです。この手法により、特定の建物に対しては高い確度での被害推定を可視化できます。現在は、集合住宅の設計・建設を主業務とする建設業者との共同研究を通じて、社会実装を展開している段階です。しかし、このアプローチは加速度センサ（SHMシステム）が導入されていない建物には適用できず、都市全体の面的な被害推定には利用できないという制約があります。第三のアプローチは、第一と第二のアプローチを統合したハイブリッド手法です。具体的には、SHMシステムが導入されている建物の情報を活用し、周辺の建物を含む面的に広がる建物群に対して、AIによる地震被害推定の信頼性を向上させるよう補正を行うものです。これは、カーナビゲーションシステムに例えると、GPSと車載センサを組み合わせて車の位置を推定する仕組みに類似しています。

第三のアプローチの実現には、SHMデータの共有（部分的なオープンデータ化）が不可欠ですが、その実現には制度的な課題や、利他的行為の必要性といった障壁などが多く存在します。そこで金子氏は、CesiumJSを用いた魅力的な可視化によって、この手法の必要性を段階的に社会へ示すことで、第三のアプローチの実現を目指しています。その取り組みの一環として、市民が日常的に活用できるWebアプリケーションが一般公開され、地震被害情報への理解や将来的な地震リスクへの関心を高めることが期待されています。

Cesiumを用いた最初の可視化実装には約2週間かかりましたが、その後はさらに湧き上がる興味が学習を後押ししました。Project PLATEAUの3D都市モデルのほかにも、気象庁や国土地理院、防災科学技術研究所、USGS（アメリカ地質調査所）などが公開する様々なオープンデータを活用して、CesiumJS上での3D可視化を実現しました。その後は少しずつ開発を進め、地震被害推定について開発したAIをOpen Neural Network Exchange(ONNX) ファイル形式でCesiumJSに統合するなど、数ヶ月程度で研究に活用できるレベルまで到達しました。

MeSM では、例えば2021年東北地方太平洋沖地震で観測された地表の加速度記録を3Dで対話的に閲覧することが可能です。（画像提供：金子 健作 博士）

さらに、MeSM では、人が体感できない小さな地震も含めて、震源の分布を3Dで表示し、回転アニメーションを通じて立体的に視覚化しています。（動画提供：金子 健作 博士）

さらに、MeSM では、人が体感できない小さな地震も含めて、震源の分布を3Dで表示し、回転アニメーションを通じて立体的に視覚化しています。(動画提供：金子 健作 博士）

MeSM visualizes earthquake epicenter distributions in 3D—even for small, imperceptible quakes—enhanced with rotating animations to provide a spatially intuitive experience. Courtesy Kensaku Kaneko.

MeSM by Kensaku Kaneko

3. Cesium Certifed Developerの取得と今後の研究の展望

金子氏がCesium Certifed Developer (CCD) の取得を考えたのは、Cesiumの知識修得の過程で恩恵を受けたオープンコミュニティーに恩返しをしたいという思いからでした。当初はJavaScriptもGISもまったくの初心者でしたが、1年でCCDを取得されるに至りました。

「Cesium Certified Developerには、地理空間情報やWebアプリケーション開発の専門家が応募するに値すると感じていました。最初は応募を躊躇しましたが、他分野からの積極的な参加がコミュニティーの発展に繋がると考えて、応募しました。」

金子氏は、継続的にCesiumJSを活用して研究を発展させるとともに、若い世代への教育や防災意識の向上にも貢献する考えです。彼が所属する大阪公立大学は、都市型の森之宮キャンパスを2025年に開設予定です。今後は、そのBIM（Building Information Modeling）などのデータをCesiumJSなどで活用し、都市から建物の室内までを結びつける新たな地震防災とSHMの挑戦に取り組んでいくようです。

2025年秋に開学する大阪公立大学の都市型森之宮キャンパスのCG（画像提供: 大阪公立大学）

金子氏は、これからの展望について次のように語ります。

「3D地理情報の可視化は単なる技術ではなく、社会に貢献する手段です。見慣れたデータであっても、3D表示やさまざまなデータとの重ね合わせによって、新たな発見が生まれることがあります。その発見はユーザーごとに異なり、他者と共有することで、より多様な視点が生まれることが期待されます。」


CesiumJSを使用して、2Dでは見えなかった地理空間のインサイトを容易かつ効果的に視覚化し、分析する方法を学びましょう。

The Journey of an Earthquake Engineering Researcher Utilizing CesiumJS—Structural Health Monitoring in the Digital Twin Era

This article highlights the challenge taken on by Dr. Kensaku Kaneko from Osaka Metropolitan University. Specializing in earthquake engineering of buildings, Dr. Kaneko has recently been engaged in research on structural health monitoring (SHM) using AI. SHM involves installing accelerometers in buildings to automatically assess their structural safety immediately after a major earthquake. To promote the adoption of this SHM system, Dr. Kaneko is pioneering a new approach—visualizing building safety through 3D Web GIS.

Accelerometers used in SHM record the building's response during an earthquake. These sensors can automatically upload data to cloud servers. Courtesy Kensaku Kaneko.

Dr. Kaneko’s interest in CesiumJS began in 2021 when he came across an article on Japan’s Project PLATEAU—a national initiative to develop and release 3D city models as open data.
 “At the time, I had no prior experience with GIS. However, I learned that the PLATEAU Viewer used CesiumJS and decided to try it myself. I was deeply drawn to the ability to seamlessly visualize scales ranging from thousands of kilometers down to just a few meters inside a building without losing a sense of scale,” recalls Dr. Kaneko.

What began as a simple curiosity turned into a deep interest, as he became captivated by CesiumJS’s flexibility for 3D visualization. Experiencing a sense of scale not achievable in 2D and realizing the potential to create open, web-based systems that could benefit society became a strong motivation. As he learned to efficiently render large numbers of entities and display both above-ground and underground structures in CesiumJS, Dr. Kaneko used resources like the Cesium community forum.

An example of a web-based visualization combining projected tsunami inundation depths in Osaka, 3D city models, and emergency evacuation sites. Courtesy Kensaku Kaneko.

2. Application to research and implementation

Dr. Kaneko is conducting advanced research that integrates AI-driven large-scale earthquake damage estimation with SHM. CesiumJS plays a vital role in this endeavor. He envisions SHM becoming as commonplace and familiar to the public as dashboard cameras in the future. AI, he believes, will play a key role in accelerating SHM’s widespread adoption.

Through this research, Dr. Kaneko developed MeSM, short for Machine Learning-Enhanced Structural Health Monitoring. A simplified version of the system—excluding the SHM logs and AI functionality—is publicly available. This web app is already being used in disaster preparedness courses and educational programs.

The research project is built on three core approaches:

Using earthquake data (e.g., epicenter location, depth, magnitude) from the Japan Meteorological Agency and integrating pre-trained AI models with 3D city models to estimate urban-scale earthquake damage in real time. This allows visualization of damage across hundreds of thousands of buildings using CesiumJS. This method involves a degree of uncertainty in its predictions.

By installing a single accelerometer in a building and combining its data with structural design information, it enables more accurate damage estimation for individual buildings. This approach is currently being applied through joint research with a construction firm specializing in residential buildings. This is not suitable for buildings without SHM sensors and thus does not support area-wide damage assessments.

Warfighting, Software, and the OTA

Cesium Releases in July 2025

Draping Imagery over 3D Tiles in CesiumJS

Cesium Roadmap for Bridging the Built and Natural Environment

Hobu's Eptium Visualizes Country-Scale Point Clouds with CesiumJS

耐震工学の研究者が歩むCesiumJS活用の軌跡　-　デジタルツイン時代の構造ヘルスモニタリング

Cesium Releases in June 2025

Warfighting, Software, and the OTA

Cesium Releases in July 2025

Draping Imagery over 3D Tiles in CesiumJS

Cesium Roadmap for Bridging the Built and Natural Environment

Hobu's Eptium Visualizes Country-Scale Point Clouds with CesiumJS

耐震工学の研究者が歩むCesiumJS活用の軌跡 - デジタルツイン時代の構造ヘルスモニタリング

Cesium Releases in June 2025

耐震工学の研究者が歩むCesiumJS活用の軌跡　-　デジタルツイン時代の構造ヘルスモニタリング