I started this architectural modeling journey to learn how to model any kind of building, by revisiting classics and some favourites of mine along the way. Down the road , there always was one name that I knew would really pose a challenge : Zaha Hadid.

Being familiar with her style, which I both like and admire, I knew it would take a lot of knowledge and some specific tools to manage to replicate it. The organic, freeform and unbound shapes of her architecture : those were the challenge.

Link towards 3D model files for download on CG trader

The impulse of the project

Amongst the huge library of Zaha Hadid’s works, I always had an attraction for two of her Austrian projects in the early 2000s. The monumental ski ramp and the Nordpark Stations in the city of Innsbruck.

There was something about the out-of-this-world nature of those projects, especially the Nordpark Stations. Their shape was hard to associate with any kind of train station, but the compelling part was the dialogue between the curved shaped roof, both floating and melting, and the more generic geometry of the station platforms and stairs.

So there it was, if I had to tackle a Zaha Hadid project, this was the one. It had pretty much all the trademark characteristics of her work, and also seemed quite reasonable in terms of scale.

For the both the shape and the simplicity of the environment, I settled on one of those stations, the second one, just before the train tracks cross the river.

Geeting started

As usual, the first step is to gather as many visual references as possible in order to eyeball every little inch of the project. The software Purefer is excellent for pasting all those references in one place and allows to check them in detail one by one, very fluid and very fast.

As for the 2D reference, a longitudinal section of the station was the best I could find. No plans, no elevation, this would have to be enough.

Planning a strategy for the model

I wanted to focus on the roof, this was the main course, the rest of the environment was pretty basic and I hadn’t settled on a limit just yet. So first, the roof, the Zaha Hadid kind of roof, then we’ll expand a little to give it context.

Of course this is no ordinary shape, there is no clear geometrical element to start from. No clear drawing rule, no dimension. Best way to apprehend it is to observe and take notes.

Sketch preparation

This step is pretty important in my workflow, as it’s a way to plan ahead on what to do when you’re creating a new 3D file.

First thing is to find some sort of logic inside the shape, in order to replicate it on the model. Staring at the picture, I can read vertical lines going all along the roof, 30 of them, with pretty much the same distance between them. This means subdivision, but subdivision of what ?

Looking from the front of the stairs, I see the thickness of the roof, roughly the same everywhere. I can then visualize the base shape as a flat surface, with a shell all around it. Good, since it’s easier to work with something flat, like a plane. But what does that plane do ?

It bends, like it’s wrapped around a virtual cylinder. It stretches on the side to the right and to the left, so that it touches the concrete stairs, the ground and the platform, with different lengths, at different points, easily located by counting the vertical subdivisions.

By now, the plan starts to get quite clearer :

• Create a plane
• Subdivide it by 30×3
• Stretch it on both sides
• Bend it
• Shell it for thickness
• Turbosmooth it for geometry subdivision and curving

3D modeling on 3dsmax

The software I use is 3dsmax, it’s where I learn to create more complexe shapes with some powerful tools : the Edit poly modifier and the Turbosmooth. Basically, I can add layers of modifications to every part of my geometry, all the while subdividing it to see how it bends and curves itself.

The 3D modeling principles used are more thoroughly described in this post (3 basic principles for 3D modeling on 3dsmax).

Nordpark Station model V0

Creating a new file, we set up the reference inside the software by creating a plane, assigning it a material with the section jpg image as a texture. It’s our canvas on the screen.

Stack of Edit poly modifiers

Once I have the base section in sight, I create the base plane with the 30×3 subdivision. I’ll need to stretch it and bend it to match the shape I see. Each time I start poly editing by modifying vertices, adding edges, and so on, I always check how it looks subdivided (=smooth and curved) and make corrections based on my eyeballing skills.

No measures, just approximations, following the logic of the shape. A lot of trial and error, adjustments on all angles, this part takes time and the result cannot be perfect. 

In the end, done is better than perfect, so we move on when we get to the point of a good geometry, with good topology, that resembles enough the Nordpark Station.

It took around 9 consecutive Edit Polys and around 4 hours total, but the hardest part is done.

Important model details : the cracks

The cracks separating the sheet of curved glass are very important both for the model and for a better understanding on how the actual projects is built.

Hopefully, we now have a correct geometry, neatly subdivided, which means we have enough edges in here to make these cracks appear.

We’ll have to select those edges manually, little by little, as shown below, extrude them, bevel them to disappear under the remaining polygons that become the glass sheet.

By examining the delimitation on the real roof, I understood that the cracks were marking the size limit of the sheet, considering how they could be manufactured. Not too long, not too wide, not too curved. Cracks on the middle of the thick edge are here to make it easier to assemble along the underlying metallic structure.

Supports on the stairs, the platform and the ground are pretty well concealed under the bottom curves of the roof, very ingenious. Also, a portion of the roof top is caved in, for water drainage I assume.

End of the road

There you have it, the model’s main subject is dealt with. All these steps, this is what needs to be done to approach something like Zaha Hadid’s design. That’s good to know for the future if I feel the need to go crazy on some project of mine. This kind of model does require some tweaking, poly editing and subdivisions to look convincing enough.

After that, the environment modeling is pretty standard, no need to spend too much time on it. A google maps reference is useful to place on the top view to align the sidewalks, road, bridge, street lights, etc.

3dsmax renders with Vray

Here are some V-ray renders of the 3dsmax file after all the modeling is done. Some materials were applied here and there but nothing too complicated. Street furniture was added around the station to give it some sense of urban context, including the hand made railings :

Moving on : Scene creation in Unreal Engine

Now the geometry is taken care of, let’s see what we can get out of a more powerful rendering engine, namely Unreal. This software is pretty great for real time rendering with high precision.

The tool we’ll need to bridge 3dsmax to Unreal is called Datasmith. It allows to import all of the 3dsmax file with a pretty good accuracy in terms of layers, names, materials. The updating possibilities are also a good feature in case some geometry needs correction along the way.

A little bit of touch up needs to be done inside Unreal Engine to improve the following : lighting, material, population, renders.

Lighting

First, by placing artificial lighting on the street and ground lights, all giving a better sense of volume under the roof.

Then, by using the Ultra Dynamic Sky & Weather plug in for a realistic looking sky, with customizable cloud coverage and eather conditions, such as rain and snow. You can even create puddles and ripple effects on very flat geometries with varying rain drops. Pretty neat.

PBR materials

All materials needs to be recreated inside Unreal to gain Physically Based Rendering settings, like roughness and normal maps. Best to start from a great template like the Megascans material, and make instances of it with the appropriate textures for our model.

Population

We can add foliage, trees, people, pretty easily inside of Unreal, using the Fab plug in, with free ressources that can give more life to our scene : grass, 3D people, trees.

Decals can be used to give some more details, like leakage on the concrete edges.

Animation render sequences

Finally, we can place some cameras, and create different animation sequences where our cameras fly through the scene to capture the beauty of the architecture as we imagined it when we first started working on this model.

For the making of the Nordpark Station 3D model (all the step-by-step 3D modeling process) as for a virtual tour of the completed scene in Unreal Engine, here is the overall summing up video and tutorial :

Conclusion

This project sure was interesting to dive into and worth it in terms of modeling technique. In the end, it was all about understanding the logic of the shape, before it became too complexe.

The use of topology in a software like 3dsmax really came in handy to replicate (and appreciate) the geometry of Zaha Hadid’s Nordpark Station. The trick was only to match the subdivision of the geometry in the 3D model to the separation of the curved glass panels in the real project. Or at least trying to.

The overall process was rather quick in terms of modeling, I’d say around 7 hours total including the rest of the environment.

After importing in Unreal and starting to get real time rendering quality of the scene (all of which took roughly 10 hours until final renders), it then became really fun to sort of visit the model and imagine what it would be like to take the train in Innsbruck, in such an original set up.

Still cheaper than a round-way trip to Austria, either way I don’t even ski.