Review
From Revit to VR Greg Corke gets hands-on with three Virtual Reality (VR) applications that work seamlessly with Autodesk Revit, weighing up their capabilities and assessing how well they combine with the HTC Vive and workstation GPUs.
V
irtual Reality (VR) is one of the most exciting technologies to hit the AEC market in years. Architects, engineers and clients alike can experience a realistic virtual prototype of a building long before it is built. A fully immersive VR experience gives you a sense of scale, depth and spatial awareness that simply cannot be matched by a rendering, walkthrough or physicalscale model. The feeling of presence – of existing inside the 3D model – is quite incredible. Users have the freedom to
explore a building at their own pace, to understand how it will feel and function. Walking across rooms, teleporting through doors, peering around corners – it’s all possible with a fully tracked roomscale experience. The impact on the design process can be huge – but only if VR can be used at the precise moments where it adds most value. It’s fine to wait days or weeks for an expert to produce a polished VR experience for communicating proposals to the client or the team. But for VR to truly influence design, it is the user of the
Autodesk LIVE 1.6 Autodesk LIVE has many different components – a Revit plug-in, a cloud service that creates .LVMD files and a standalone Autodesk LIVE Editor that reads/writes .LVMD files. There’s also a free viewer, Autodesk LIVE viewer, which is available for Windows or the iPad. This reads .LIVE files published by the Autodesk LIVE editor. The VR capability is only available on Windows. To prepare a model, simply create a 3D view in Revit, then go to the Revit add-ins tab and click the ‘Go LIVE’ button. The software then does some pre-flight checks on the model and alerts you to any aspects that need your attention. This includes textures that can’t be found, section boxes that you might want to turn off and levels of detail that you might want to enable so that you can see all the model geometry. Missing textures need be re-mapped manually. If they aren’t, the objects will just appear plain white. All other
16
issues can be sorted out at the click of a button without leaving the dialogue box. Hitting ‘Go’ will upload your file to the cloud for processing. As Revit files often stretch to hundreds of MBs, upload speed is important but, when on a decent connection, it is processing time that takes up the bulk of the process. On average, with 0.5Mb/sec upload, we found our 100MB to 200MB Revit test files took around 15 mins to upload, process and download the resulting .LVMD file to our desktop workstation. Larger files can take a lot longer. Also, depending on how busy the Autodesk LIVE servers are, you can end up in a queue, which can add a significant timelag. .LVMD files can be opened in the Autodesk LIVE Editor, a real-time desktop game engine design viz environment that also has a VR capability. For this article, we’ll start off by looking at what can be done on the standard desktop application and then share our
Summer 2017 special edition
experiences of VR. For navigation, use the mouse to orbit around a building or select a 3D viewpoint inherited from Revit. Alternatively, with ‘tap and go’, click on any location and the software will walk you there, automatically navigating stairs and doors. You can set the view height so it’s possible to see what an adult, toddler or wheelchair user might experience when interacting with the space. Models can be viewed in different display styles, including a clay type render mode, which is useful for early-stage design, when the focus is on form and volumes. The default fully rendered setting shows you fully baked materials and ‘realistic’ RPC content, including people and trees. Overall, the render quality is very good. Autodesk LIVE also includes tools to explore daylighting. Simply move time and date sliders and shadows adjust in real time. Revit lights can be set to turn on automatically at night. One of the most powerful capabilities of Autodesk LIVE is the ability to view the underlying BIM data within
CAD/BIM software that must have full control over when to enter the virtual environment. This gives them the opportunity to explore alternatives, evaluate the impact of modifications and detect errors early. Discovering issues weeks after a design has progressed can create delays and ramp up costs. This presents a huge opportunity for software developers to create push-button workflows to move quickly from CAD/BIM to VR. Such tools not only bring in the model geometry but also materials and lighting, so nothing needs
the model. Simply click on any object and the data appears in a dialogue box. Moving into VR is easy. Simply click the VR button in the bottom right hand corner of the screen, put on the VR headset and you’ll see a bird’s-eye view of the model – the so-called Mini Map. The model is placed on a hoop, which the user can grab, spin and pull closer to the face to inspect from any angle. It’s a really good way to get an overall view of the project and to quickly zoom in on details. It’s possible to return to the Mini Map at any time, simply by pressing the Vive’s trackpad, which can be really useful for getting your bearings. Most of the navigation in VR is done by teleporting. Simply use the HTC Vive trigger controller to point and click. In a flash, the model fades in and out and you’ll find yourself in the new location. Depending on the size of your room-scale set-up, you can also walk short distances. Doors open simply by looking at the them. This adds to the realism and your understanding of the build-
ing, but can be a little annoying if you simply want to see the detail of a door – a glass door, for example, which you can see through anyway. Unfortunately, most of the functionality from the Autodesk LIVE game engine experience is currently not available in VR. You can’t interrogate the model, nor change the time of day in real time without pressing ESC, taking off your headset and swapping VR controllers for a mouse. Autodesk LIVE VR is currently very much a navigation and viewing experience – albeit a very good one. However, it’s likely that Autodesk will add more functionality to VR as it works out the best way for users to access more advanced capabilities. The visual experience in Autodesk LIVE is very good. This can be further enhanced with Autodesk Stingray, the underlying game engine technology on which Autodesk LIVE is built. Autodesk LIVE models taken into Stingray can also be turned into fully interactive experiences (think light switches, running taps, TVs or adding mechanisms to flip
www.AECmag.com
