Visualization of a Boeing 777. 3D modeling and rendering a photorealistic aircraft interior.

Boeing or Airbus?

When I moved to London in 2008, Airbus was just starting to deliver the first orders of the Airbus A380. I remember being lucky enough to work on the 3D interior visualisation of this aircraft for several airline companies.

In a few months, I knew everything about the cabin and it was funny being able to recognise the plane from just a few details. Later, I had the pleasure to work on a Boeing aircraft interior. I can't remember if it was a 747-800 or a Boeing 777 but I clearly remember feeling privileged and excited working for airline companies.

I personally find aircraft interiors extremely photogenic. Although the cabin is narrow, it's an absolutely interesting subject to portray, experimenting with different lighting conditions, camera lenses and depth of field. Also, they tend to look very photorealistic!

Designers and CGI.

With this article, I would like to offer an insight on the process of creating a set of 3D images and a 360 panoramic to showcase the design of an aircraft interior. Most of the designers are already familiar with a 3D software, be it Autocad, Vectorworks, Rhino or 3Ds Max. The web is full of tutorials about residential interiors and automotive renders. I couldn't find anything about aircrafts and I am sure you'll find this it an interesting topic. This article is not only for 3D artists. It's aimed at designers who wants to understand the process of creating the visuals and the benefits of visualising an idea before it is built. Arteconi CGI specialises in 3D Visualisation for the design industry and aircraft interior visualisation is one of the areas we focus our efforts on. 

The reasons why a designer would rely on CGI are few: to illustrate the seating design, to create different colour and trim options, to make a lighting study , to analyse the space and ultimately to present their ideas to airline companies. CGI is the vehicle to communicate ideas and a great image is often worth more than 100 words. Images have an impact at an emotional level. They get engrained in the memory of the buyer so make sure to rely only on the best 3D Visualisation Studio.

For this exercise, I have used 3ds Max, Corona Renderer (thanks to Davide Chicco for suggesting it) and Photoshop.The tutorial is software agnostic though. The same principle is easily achieved also in Maya, C4D or any other software of choice.

The process in a production environment.

There are two paths to go when a design firm commission the visualisation of an aircraft interior and both ways have its pros and cons.

Option A: The 3d model is provided by the client from the CAD software.

In this case, the work consists of cleaning the CAD model received, making it lighter and prepare it for the materials.

Often the case is to create a shell around the cabin to block any potential light leaks of the sun or skylight entering those holes.

Most probably you would have to remodel the seatings since they will need decent mapping and details like stitches, folds and creases that are usually not present in the CAD model. Generally, they look stiff and boxy and since your client is most probably the designer of the seating you'll have to put some more effort into them.

Pros: The model is detailed and there's not much modelling involved.

Cons: Heavy Geometry. UVing. Whenever you have a problem with the geometry it's probably faster to remodel than fix. The 3D model could be hard to manage in the viewport and selecting different elements might not be straightforward. 

Option B: Model it from scratch. 

The Pros: We can deconstruct the aircraft into few elements and keep the model very light. Using symmetry, instances and xref we'll be able to achieve great results still retaining control over the model and performances in the viewport that are vital to accomplish a good job. Also, we'll have deeper control on the texturing since we'll be able to create UVs along the 3D modeling process. In general, you're less exposed to surprises since you're in control of the entire scene from the beginning and you can keep on eye on polygon number, texturing issues and model elements according to your needs and complexity.

The Cons. The downside is that the model won't be as detailed and accurate as the CAD data but most of the time it will be good enough. I am especially referring to the area where the fuselage tapers towards the nose of the aircraft, doors, emergency exits, hostess seats and bar areas. Everything could be modelled but I will put into account a few compromises in terms of level of detail to keep the budget reasonable.

In this article we'll go through this second option: 3D modeling the fuselage and assembling a section since it is the funniest route. 

We'll then add a commercial 3D model of a seat bought from TurboSquid and proceed with lighting, shading and rendering.

Here we go!

References and other online resources.

The hardest task in this project was to find information about the cabin.

With a bit of luck, I found a cross section of the aircraft on Google. I have used this as a base to trace some lines that I have later extruded and transformed into a section of the fuselage. Also, I managed to find few more vital pieces of information on two forums: Cardatabase and Flyertalk. The dimension of the window is 27cm. x 38cm. and the section itself is 53 cm.

One of the most important aspect while creating a photorealistic image is to collect photo references. 3D Artists often acts on memory for their reference. I am one of those and I admit that it's easier to get lost or mislead by what you think it makes sense. Always rely on images for your 3D modeling, lighting and shading but also search for plans, elevations and blueprints of your subject before getting into any kind of detail.

Google Images is the place to start for photo references, alternatively, you can try Flickr and Pinterest or Getty Images and ShutterStock if you are ready to pay.

Another underestimated step is to get the volumes and masses right. You don't want to spend a few days modelling your seat just to later realise that it doesn't fit the fuselage. Block out the volumes based on as many info you can obtain and then move on to small details. It's always more painful to get backwards then do things correctly from the beginning.

Google is your best friend not only because of the search engine but also because of Sketch-up Warehouse. At least it used to be Google.

The 3d models you find there are usually low res but very often they are in scale. This means that you can use them as a reference for the proportion of your 3d model. Not to mention the fact that you can use them to populate scenes in the distance or as background elements that don't require a high level of detail.

Another thing to consider is momentum. Every project has a curve of excitement. After few days of looking at the same elements you won't have the spirit and inspiration that you had when you started, so, exploit the momentum and make sure that everything falls into place from the start so you won't feel like going backwards later on.

TurboSquid is the place to go when you need ready made 3d models for your project. They have all kind of 3d models, either commercial or free. In this case, I bought the 3d model of the seating that I have later used and adapted to this aircraft from a 3D artist called Diesel_V.

The model I used is this one:

http://www.turbosquid.com/FullPreview/Index.cfm/ID/791610

Once gathered all those info and material I have created a ContactSheet of the reference images in Photoshop.

The measurements, the section and the contact sheet have been constantly on my 2nd screen ready to compare my progress.

Modeling a section of the fuselage.

Looking at the pictures we can easily breakdown the fuselage into identical repeated sections. For practical reasons we'll make the lighting, aircon and luggage compartments to match the length of a double windows section. In reality, those modules are offset from the windows section and are used in modules to match the size of the seating but for this exercise, we'll make them the same length: 106 cm.

The first part I focused on was a single window panel. If you have any knowledge of poly-modeling you'll recognise how simple is the model. If you don't I warmly suggest you to pay a visit to Grant Warwick's website where you can find one of the best hard surface modeling course around. He will take you from zero to hero in no time. There's also a free video on youtube showing basic techniques of hard surface modeling.

The process is very easy and takes advantage of the symmetry modifier. I have traced a line from the cross section and extruded it of 53 cm. making sure to have enough subdivision to proceed. After that, I have added a symmetry modifier and started to work only on half the model since the rest gets reflected on the other half. To create the window I have used the cut tool trying to follow the shape of the window. Then I have refined it moving vertices and chamfering extra details. To finish it I have created the double window with the symmetry modifier again and used a turbo smooth modifier on top to give more resolution to the mesh.

An important step was to create an external shell to protect the plane from light leaks. The sun light and skylight are very strong and the fuselage is always in a high contrast lighting condition. The extra panel is not visible from inside the aircraft since it is in line with the window but serves to avoid artefacts from the rendering engines.

After the double window panel was ready I proceeded adding details. The grid in the lower part is just a series lines with different bevel profiles and the window cover is a simple exercise of poly modeling.

Modeling the upper fuselage. Lighting, Aircon and Luggage Compartments.

Continuing on the fuselage, I have extruded few more lines from the cross section until I reached half of its profile. Again I have used the symmetry modifier to mirror the right side of the fuselage.

The details of the lighting and of the aircon are simple poly modeling exercises achieved using the cut / move / shell / chamfer / connect / turbo smooth tools.

Again there's a grid element modelled as the previous one, a series of lines with a bevel profile modifier for the grid and a different profile for its frame.

As you can see once a full section is ready I made sure that every area was protected from light leaks creating a shell all around the section.

Modifying the seating.

The seating is a commercial model bought from Turbosquid.

The only modification I did to this model was to sculpt some folds on the headrest to make it look more organic. After that, I have created a version of it with three seats for the central row. Again this was easily achieved by using the symmetry modifier and then cleaning up some small geometry problem generated by the modifier. 

Cloning the elements and adding the end walls and curtains.

The next and very important step were to clone the section of the fuselage and the seating. Make sure that the sections are exactly 106 cm wide and clone them at this same exact distance to avoid problems with the light leaking in the geometry. So far, the model remains very light and easy to edit because everything is instanced. The next step was to add a shelled plane for the carpet, the end walls, the curtains and the exit signs.

Again the modeling is extremely simple. The curtains are subdivided planes with a noise modifier and the exit signs no more than chamfered boxes.

Lighting and Shading in Corona Renderer.

This is my favourite part of the job together with modeling. Lighting in Corona is natural and easy. There're no tricks involved.

I have used the Corona Sky in the environment and Corona Light portals on the window glass geometry. 

To light up the cabin I have added some Corona Lights set as a plane in correspondence of the window wash light and above the luggage compartments. Essentially I have cloned these same lights together with the fuselage. To keep things consistent I have researched the web on this type of lights and found out few info on kelvin temperature and intensity here: http://www.sela-light.com/lighting-refurbishment/

Also, I have used few IES spotlights in correspondence of the spotlight geometry. Again, I have just tried to keep the intensity real, I think around 400 lux.

I won't be digging into shading for two reasons because it was very simple and there's lot of tutorials on this topic on Ronen Bekerman's blog.

One tedious job was to give variation to the magazines and screens. I took the freedom to get few screengrabs of my favourite movies, I am sure you'll recognise some of them.

Rendering and Post Production.

The beauty of Corona is that you don't have to fiddle with the render settings. Render settings are default, just using the UHD cache as secondary rays. No other modification.

The rendered images are color corrected in the Corona Frame Buffer where I changed exposure, burn value, contrast and white balance.

In Photoshop I have opened the renders in camera raw and colour corrected the values again but to be honest the images didn't need too much of it.

360 Panoramic View.

Everything is extremely easy in Corona and so is creating a panoramic view. Just make sure that the proportion of the image is 2:1. I have used 6000x3000 px but you can go higher to 8000x4000 px or 12000x6000 px. if you want to be able to zoom in without losing details.

I have used a Corona Camera Modifier to set the projection override to spherical. This is it, just hit render.

With the last version of Corona, you can render also in stereoscopic 3D and use it with Oculus Rift or, in alternative, use a smartphone supporting a VR headset or google cardboards.

This article is extracted from our website blog: www.arteconi-cgi.com/blog/

Arteconi CGI is expert in producing CGI images and animations for the design industry. Aircraft interiors 3D visualisation is one of the areas we specialise in.

www.arteconi-cgi.com