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Design Innovation Research CentreWorking Paper, Number 6from the start. Think of it like a car: A car with an aluminium body will be considerably lighter thanone with a steel body, and, if someone with a steel car wished to make their car lighter, they couldchange the body to aluminium although it would have been far easier to have had an aluminium carfrom the outset. In short, the models will often need to be re-drawn with simpler geometries for alighter body e.g. instead of creating solid information-intense objects such as cubes, you can createthe same cubes in a hollow and less information-intense manner by using six flat surfaces; themodel will be much lighter if it is originally created in this manner3. Object nomenclature - It is a good idea to name objects in a model in a unique, butcomprehendible manner (not just a series of numbers or “wall42”, for example) and assign texturessimilarly; this can make things a lot less complicated if there is a need to edit the model in Unity at alater stage.4. Duplication of texture-assignments - Where possible, assign textures in hierarchical clusters;ensure objects with the same textures share those textures, rather than ‘creating’ and assigning thetextures twice. This can significantly reduce draw calls, thus increasing performance. In certainsituations, merging meshes can have substantial performance benefits; however, in cases whereocclusion culling needs to be used, if part of the mesh is out of the occlusion area, the whole meshcan disappear.5. Rectangular texture images - Ensure that your textures are square and to the power of two, e.g.2048 x 2048. Unity supports all image formats; however, there have been some occasional issueswhen loading JPEGs.6. Exporting two-sided materials – Reversed faces are not visible in most visualization packages, thusthe modeller must bear in mind which faces will be exposed when immersed in the model andcreate it accordingly. However in the case that the models have already been created, the models’components will need to be exported with two-sided faces; this will double the number of polygonsand have a significant impact on the file size. This will only be an issue on large models wheremodel-simplification is of upmost importance. Many of the vendors do not provide the ‘export twosided faces’ option, but will instead do it automatically. Navisworks is as an exception to this; itneither provides an option, nor does it automatically export two-sided materials.7. Inconsistent formatting throughout the software vendors - Although it may seem from theinteroperability table (reference table) that different programs can be linked via certain formats, itis important to realise that there is no single best format for all of the workflows due to thesignificant variance in the files exported by different programs’, even when their format type is thesame; the exported files are only as good as the way in which the program exports them. Forexample, the FBX created by SketchUp varies significantly to an FBX created by Revit; Revit 2013encrypts its exported materials, making them unreadable by Unity, whereas SketchUp exports itsFBX files with a separate materials file that is readable by Unity. There is an absence of cohesionbetween the software vendors that is especially made apparent by the lack of interoperability whenusing the “collaborative” Industry Foundation Class (IFC) format which is written and interpretedWP 6, v 1.08

Design Innovation Research CentreWorking Paper, Number 6differently by each software vendor, resulting in hiccups such as distorted geometries and missingtextures when an IFC is read by non-native software4Discussion and ConclusionsThe contribution of this working paper is to document workflows that can be used to prepare large modelsfor real-time immersive viewing with high-end display solutions. This is particularly pertinent as theconstruction sector begins to use Building Information Modelling (BIM), which is now mandated for use inall UK public procurement by 2016. Immersive visualization facilities have been available for some time(Whyte, 2002), but there are new opportunities to use immersive facilities such as the ComputerAutomatic Virtual Environment (CAVE). Many of these are now being upgraded as hardware improves andbecomes cheaper, with experiments to use next generation software (e.g. Steptoe, 2013). In the Universityof Reading, as elsewhere, the CAVE has also been reconfigured to operate under the Windows operatingsystem, using Unity3D and MiddleVR. Research is on-going to use the CAVE for other built environmentvisualisation applications (e.g. Tutt & Harty, 2013).We had most success with model flows from Trimble SketchUp Pro and Bentley Microstation for rapidlyviewing and interacting with models on high-end display equipment and visualisation systems when usingthe Unity3D game engine. SketchUp Pro provides a good starting platform for workflows concerning highend visualisation, it; has a simple and intuitive user-interface, creates impressive results which can befurther enhanced by its wide selection of plug-ins, and has the ability to retrieve geospatial informationfrom Google Earth. However, for large complex models, Microstation facilitates an agile transferral withcomparatively less triangulation than SketchUp and enables the modeller to alter the stroke tolerance.The findings of this study can inform the set-up of future practical work.5ReferencesPenn State. (2013). Work Flows Retrieved 8 August, 2013, from http://bim.wikispaces.com/Work FlowsSteptoe, W. (2013). Using Unity and a Kinect in CAVE-like systems Retrieved 8 August, 2013, unity-and-a-kinect-in-cave-like-systemsTutt, D., & Harty, C. (2013). Journeys through the CAVE: The use of 3D immersive environments for client engagementpractices in hospital design. Paper presented at the ARCOM, Reading.Whyte, J. K. (2002). Virtual Reality and the Built Environment. Oxford: Architectural Press.WP 6, v 1.09

Design Innovation Research CentreWorking Paper, Number 6APPENDIX A: Using Unity1. Creating a new projectTo start a new project:File New Project Figure 3: The project wizard in UnityThe project wizard will appear where you can choose the project’s directory and which standard assets you wish toimport. In most cases, you will want to check: Character Controller; Light Flares; and Skyboxes.2. Importing and utilising assetsIf you have already created a project, but wish to import other standard assets, simply: Assets Import Package Select and import required package. Creating a project will create three folders within the project directory: Assets,Library, Project Settings.Once you have created a unity-ready model, you can then simply place the model into the project by either:Dragging the model and any textures folders across the desktop and dropping into the ‘Assets’ panel within Unity;or, placing the model and any texture folders into the ‘Assets’ folder of the project directory. Within Unity, theproject will automatically appear in the ‘Assets’ folder under the ‘Project’ tab.Figure 4: The Assets folder in UnityWP 6, v 1.010

Design Innovation Research CentreWorking Paper, Number 6If you select the model in the assets folder, the ‘Inspector’ tab will appear in which you can change the modelsettings. Here, you can add colliders and scale the model accordingly. Select ‘Apply’ to implement the changes.4. Creating a basic scene and previewing in game modeTo get a model into a scene, drag and drop the project under the ‘Hierarchy’ tab. If you wish to preview the model inreal-time within Unity, a first person character controller can then be dragged and dropped straight into the desiredlocation within the scene.To add a skybox to the scene: Edit Render Settings Select the point to the right of ‘Skybox Material’ search andselect the desired skybox.To add a sun to the scene: GameObject Create Other Directional Light. In Unity, the directional light provides aninfinitely constant flux of light, thus it can be positioned close to the model with the same effects. To make the sun alittle more convincing, you can add a sun flare by selecting the directional light in the ‘Hierarchy’ tab, select the pointnext to ‘Flare’ which appears in the ‘Inspector’ tab and then select the sun flare.Figure 5: The model in ‘game’ modeSimply press the play button to view your scene in the real-time ‘Game’ mode.WP 6, v 1.011

Design Innovation Research CentreWorking Paper, Number 6APPENDIX B: Workflows1. Autodesk Navisworks Manage 2014To export the FBX into Navisworks:Select the green ‘N’ in the top left corner Export FBXIn the FBX Options dialogue box, make sure ‘Lights’ and ‘Cameras’ are unchecked. Ensure to embed textures. Ifmodel is very large, you can try to limit the number of polygons.Figure 6: The FBX optionsUnfortunately, Navisworks does not export double-sided materials. This means, for instance, that you would only beable to see through a window in one direction. To mitigate this, ensure that the materials are rendered on the sidefrom which you will be looking at them.WP 6, v 1.012

Design Innovation Research CentreWorking Paper, Number 62. Autodesk Revit 2013WorkflowOpen up a 3D view of a project in Revit 2013 Click the ‘R’ in the top left corner Export FBX Choose a filedestination Open 3ds Max Click the green ‘3’ in the top left corner Import Select the exported FBX from Revit ‘OK’ to accept default settings Click ‘render production’ on the main toolbar (if you cannot see the toolbar, pressAlt 6) Under ‘render preset’ select ‘mental.ray.daylighting.high’ and select ‘load’ Click the green ‘3’ in the top leftcorner Export Ensure file type is FBX and save in the ‘Assets’ Directory of a Unity project Within the FBX exportoptions, ensure that ‘Embed Media’ is checked and accept the default export options Click ok to any warningsregarding the sun, sky, lighting and any cameras that may be on the project - there are less complications whenthese are configured in Unity.Figure 7: Screenshots in Revit and UnityLessons LearntTranslation from Revit was found to be the most problematic workflow. Previous to 2011, the FBX export would alsoproduce a FBM folder containing the texture properties, thus you could import straight from Revit into Unity.However, since 2011 Autodesk have changed their materials to the Protein 2.0 type, in which the textures are nowencrypted within an Autodesk library file in the FBM folder and cannot be interpreted by Unity 3D. Therefore, Revitneeds an additional intermediary step to transfer into Unity. 3ds Max 2014 is an Autodesk product capable ofreading the encrypted Autodesk Library materials and can then export FBX files with its textures embedded within itthat Unity can detect. However, 3ds Max will not export textures in areas where there is complex geometry, such asintersecting vertices.WP 6, v 1.013

Design Innovation Research CentreWorking Paper, Number 6The building’s geometries should import correctly, however, only some textures are translated where the geometryis complex. To resolve this, you can undertake some time-consuming processes: Simplify the geometries and verticesin 3ds Max to allow for a better transferal of textures; or, unwrap the UVs in 3ds Max and then map them in Unity.Using 3ds Max or some of its plug-ins, such as V-Ray, photorealistic renders can be achieved by rendering and bakingthe textures before importing into Unity. This can be a slow process.There will need to be further development on this workflow in order to establish more direct workflows.WP 6, v 1.014

Design Innovation Research CentreWorking Paper, Number 63. Bentley Microstation V8iPrimarily used for infrastructure design, projects created in Bentley Microstation V8i are usually large and intricate;there are usually many polygons and faces. I found that the FBX export was the best direct export into Unity; theexportation speed was high and there were seemingly no issues with the textures. The DAE export works well, butdoes not export textures.In any case, it is advisable to first compress the model (or piece of the model) within Bentley:File Compress DesignThis will eliminate cross-session data and useless information which has accumulated for various reasons. In mostcases, this only tends to have a slight impact on the size of the file but is worth doing.To export the file:File Export FBX The ‘FBX Export Settings’ window will appear. The stroke tolerance is usually at a default of 0.100m. You should varythe stroke tolerance depending on the size of the model. A larger stroke tolerance will reduce the rendering time,but will provide worse quality rendered surfaces, particularly noticeable on curved geometries. A smaller stroketolerance will increase the rendering time, but will provide better quality rendered surfaces. I have found the defaultof 0.100m to be too small in most cases. I have had success using a range of 0.500m to 1.500m withoutcompromising on quality too much, however,larger models will need to use a higher stroke tolerance. Also ensurethat the Y and Z axis are inverted so they will be situated on the correct axis within Unity.Figure 8: The FBX export settingsWP 6, v 1.015

Design Innovation Research CentreWorking Paper, Number 64. Google EarthSketchUp Pro enables users to capture geospatial information and geo locate a model by using its Google Earthplugin. To export from Sketchup into Unity, the terrain and the buildings need to be exported separately in differentformats. First, within a unity project, create a new folder within ‘Assets’: Right-click ‘Assets’ folder under project tab Create FolderExport the terrain as an FBX by selecting the terrain and following the FBX export process for SketchUp Pro,however, ensure that “export only current selection” is checked and DO NOT export it straight into an assets folderof a Unity project. Once the FBX has been exported, there should be a folder within the FBX’s directory with thesame name as the FBX. This folder should contain the Google Earth image of your geo location.Drag and drop the Google Earth image into the new folder that was created in Unity. It is only then that you canimport the FBX into Unity. If this is not followed, the texture will not map itself to the mesh; the mesh will be blank.The buildings downloaded from Trimble must be then separately exported as a Collada file (DAE). Follow theSketchUp export process.Figure 9: Buildings and terrain in UnityOnce the buildings and the geo location are in Unity, they can be dragged into the hierarchy and should fit togetheras in SketchUp. As mentioned in the SketchUp workflow, the Collada exports will default to using inches as the units,therefore the Collada files will have to be set to a scale of 0.0254. Also ensure that the FBX geo location is at a scaleof 1.WP 6, v 1.016

Design Innovation Research CentreWorking Paper, Number 65. Graphisoft ArchiCAD 17Although fairly slow, the best workflow from ArchiCAD is through SketchUp. Make sure that the model is in a 3Dview (press Ctrl F5), and then select File Save as Select SketchUp file from the ‘Save as type’ drop-down box Follow the SketchUp workflow for exporting a Collada .dae file. This workflow pulls through all of the textures andgeometries correctly into Unity.If you do not have SketchUp, you can export from ArchiCAD as a .3ds file and import that into Autodesk 3ds Max.From there it is best to export an FBX; the DAE exporter in 3ds Max does not export the textures as well as the FBXexporter does.6. Nemetschek Vectorworks 2013From Vectorworks, the only successful workflow directly into Unity has been by exporting a Cinema 4D (C4D) file. Todo so:View the model in a 3D view File Export Export Cinema 4D (3D only)Export the model directly into the asse

from Autodesk, Bentley, Google Earth, Graphisoft, Nemetschek and Trimble products, in a 3D fully immersive CAVE. The working paper also discusses 7 key challenges, namely; intersecting vertices, data-heavy models, object nomenclature, duplication of texture-assignments, rectangular texture images,