Scalable viz for all

LumenRT: scalable viz for everyone

By harnessing the power of the cloud together with engineering accurate scalable meshes, Bentley is looking to make model complexity a non-issue for large-scale design visualisation on infrastructure projects, reports Greg Corke

Visualisation used to be the pre- making a custom version available free of structure projects but, since it came serve of the design viz special- charge to those who use its CONNECT under Bentley’s control, this focus has ist, but this has changed dra- Edition design modelling applications. grown. One of biggest challenges that matically over the past few LumenRT Designer contains most of engineering firms face is how to handle years. Most BIM applications now have the functionality of full-blown LumenRT, the complexity of large projects, which capable renderers built in and advanced but has a slightly smaller environmental often include huge roads, long corridors tools like V-Ray are being tuned to the content library of vegetation, vehicles and vast expanses of terrain. workflows of architects and engineers. and characters. Resolution is limited to The datasets can be enormous, containWhile static rendered images continue to play an important role in design ‘‘ LumenRT can now visualise large scenes ing millions of polygons. This puts a massive load on the GPU and slows down exploration, it’s the realtime rendering tools – some of which also support using actual engineering data, without having to go down the one-way optimisation route 3D performance. Trying to navigate a complex scene at only a few frames per secVirtual Reality (VR) – that are currently generating the biggest buzz. FHD (1,920 x 1,080) and you’ll also need ’’ ond significantly impacts the experience and limits how useful it is. And you can certainly

Two years ago, Bentley Systems got its the full version if you want to take your forget about doing anything in VR. own real-time rendering technology, designs into VR. The traditional way to solve this probLumenRT, with the acquisition of E-on lem is to decimate the mesh and reduce Software. LumenRT has always been con- Handling large projects the number of polygons in the scene. This sidered easy to use, but now Bentley is LumenRT has always placed a big is fine for many visualisation workflows making a big effort to expand its reach by emphasis on the visualisation of infra- – as long as you don’t need to look too

closely – but once the data has been approximated and averaged, it’s pretty much useless for any kind of engineering calculation.

Thanks to Bentley’s new scalable mesh technology, LumenRT can now visualise large scenes using actual engineering data, without having to go down the oneway optimisation route.

The technology is based on Bentley’s 3SM format and works with point clouds, Lidar data and even standard DTM meshes.

In LumenRT, when the camera position changes, data can be automatically streamed from Bentley’s ProjectWise ContextShare service and cached on the client device, which could be a workstation, a mobile phone or a VR headset. Data comes in as quick as 0.3 seconds, says Bentley’s David Burdick, so there is no discernible lag.

Scalable mesh technology supports infinite levels of detail, so when Image courtesy limitation because of the size of you zoom in, you see more detail and when you zoom out, you see of Shenzhen Municipal Design and Research the graphics hardware – and with big terrains in there, there less. Institute just wasn’t enough GPU power to

Resolution can go down to less handle it. Now, with the streamathan 1cm. From a viz perspective, this ble format, we can do any size.” may or may not be relevant, but as Burdick gives the example of a recent Bentley’s David Huie explains, it is really 20km x 30km corridor project. “If you valuable, as the same data can be used in tried to stick this on a laptop, it would the engineering process. “You can actual- die. [With scalable mesh technology] you ly base your volumetric calculations off can stick this on the web and have it the mesh,” he says. “It’s so versatile that stream and you can run it on a phone and it’s usable for the OpenRoads guys, or for bring in this whole mesh.” someone who wants to do a site plan or in LumenRT for visualisation.” Virtual Reality (VR)

Bentley’s David Burdick describes scal- This time last year, Bentley was in the able mesh as a “game-changing technolo- process of adding a VR capability to gy” that allows firms to work with mod- LumenRT. With update 3, released this els of any size. summer, the software now supports the

“We are working with customers that Oculus Rift and HTC Vive. are doing small buildings all the way up to Bentley calls this a ‘Level 1 VR’ imple100 km square corridors, so we don’t want mentation, which is pretty much a visual any limitations. There was a theoretical experience. Users are able to walk

uses a baked, DirectX format that’s optimised for viz,” explains David Burdick. “In the future, we’re not going to do that anymore. We’re just going to work natively off an iModel kind of format and enrich the iModel to give it what it needs for LumenRT.” Bentley is also exploring how GPU power can be harnessed from the cloud. One of the challenges of expanding the reach of LumenRT to architects and engineers is that typical CAD workstations are not geared up for real-time visualisation, which needs a much more powerful GPU. By doing the graphics processing in the cloud, rather than on the client device, users can get around the problem. It also means visualisation can be done on a around, teleport, wave the wand, Image courtesy means it can handle much bigger phone or a tablet, and not just on a powchange the time of day and click on objects to access high-level of China CMCU Engineering Corporation models. In addition to working closely erful workstation. Bentley has trialled this with Microsoft and it works well on attribute information. with Microsoft’s HoloLens team, 2D screens, says Brubeck.

With December’s forthcoming update Bentley is also exploring a tablet version, VR is a different animal, he acknowl4, the ‘Level 2 VR’ implementation, users where the LumenRT scene is overlaid edges, as it basically requires doubling will be able to access a much richer level with the actual reality behind it, captured the frame rate. “We are going to get there of BIM information from inside VR. This with the tablet’s camera. However, eventually, I have no doubt,” he says, addis not only with data from Bentley’s mod- Bentley still needs to solve some chal- ing that by reducing the latency with new elling applications, but also from Revit, lenges around geo-positioning, as the tol- generation GPUs, the latency you have ArchiCAD, SketchUp and City Engine, erances are still quite high. because of the distance from the cloud for which LumenRT plug-ins exist. server becomes less of an issue.

‘Level 2 VR’ will also introduce the idea Moving viz to the cloud of ‘scenarios’, where users are able to flip LumenRT currently offers a push-button Conclusion things on and off inside VR, as David workflow. Press a button in Bentley’s With LumenRT, Bentley is looking to Burdick explains. “I’ll be able to say, just modelling applications, Revit, ArchiCAD, deliver design visualisation into the hands show me all the piping on this and show SketchUp or City Engine, and of engineers and architects. everything else with an invisible phan tom around it.” - a base LumenRT model is created automatically. ‘‘ [In the This is nothing new, of course. Most design viz software develFrom VR to MR Bentley is also exploring the potential for Geometry, layers, levels, lights, materials and BIM information are brought future] we’re just going to opers have been on this trajectory for some years. The ace up Bentley’s sleeve, however, could using LumenRT with Augmented or across and baked into a so- work be the ability to use actual engiMixed Reality – visualising your design in the context of a site. Burbeck believes that this is where development of called LightCube. David Burdick says that a typical Revit model, which is heavily natively off an iModel neering data within the visualisation, rather than approximated geometry. LumenRT will ultimately lead. instanced, can take anywhere kind of As the AEC industry

Initial research was done with the from 3 mins to 10 mins to format and embarks on a journey of Microsoft HoloLens, but the LumenRT team found that the headset had limitations for design viz, as Burdick explains. bake. All of the processing is done locally on the desktop. Once inside LumenRT, the enrich the iModel to using VR for collaborative design review, the potential to carry out volumetric calcula“With the first device [the HoloLens], the design asset can be brought to give it what tions on the engineering computer was inside the headset, so the life by adding vehicles, mov- it needs for mesh and extract rich inforproblem was once you started getting over 100,000 polygons, which is about ing people, windswept plants, rolling clouds, rippling water LumenRT mation from the 3D model could prove to be a powerful the maximum you can hold, the thing really started to heat up. and much more. Importantly, the software is able to handle ’’ future capability. In addition, by having a

“We really needed to go beyond that – change, which means updated designs direct connection to an iModel in the because our models are 4 million to 10 can be re-imported and the user does not cloud, any annotations or calculations million polygons, roughly.” have to redo the entire scene. done in VR could be stored as part of the

Now Bentley has access to Microsoft’s In the future, Bentley will move away project. In contrast, most file-based new Mixed Reality device, which con- from a desktop-centric workflow and design viz applications are largely disnects to a PC via Bluetooth or hardwire. embrace the cloud. connected from the engineering process. As the processing is done on the PC, it “Right now, LumenRT’s native format ■ bentley.com