Nexus VI

Nexus VI: how Blender was used to create jaw-dropping CGI for a Sci-Fi Youtube channel

This article is also available in: French

Romain Toumi: As for the lasers themselves, it was quite easy to create them: I used a stretched Icosphere, a little bit of subdiv, displace and noise.

These lasers are mesh lights, but they can only be seen by the camera: they don’t light the rest of the scene. I used a regular light to fake this lighting: lighting the scene using mesh lights would have taken too much time to render (even more so with the displace and noise I added), whereas a simple light is fast to render and you still get a nice picture at the end.

Above: a scene rendered using mesh lights. Below: the same scene using the faster technique.

To sum it up, each laser shot by a ship is tied to a light source. This is also quite helpful for previs using Eevee, the real-time engine available in Blender: you would not be able to do some lighting previs using Eevee and mesh lights, because Eevee does not handle bounces.

Indeed, there was a real need to previsualize these shots, so that the sound designer could know precisely when each laser & hit happened. This was also quite useful to work on the editing and to get a good idea of what the end result would look like.

3DVF: What about the explosions?

I used stock shots with alpha blending. This allowed me not to take too much time to create the lasers hitting the asteroids. I also used some particle effects I had prepared beforehand.

For the spaceships on the other hand, I used a different technique. If you take a look at the destruction of the small fighter ship with an embedded camera [Editor’s note: 15’58”], you can see the lasers up close. I did not use my shooting system, each laser/impact was carefully placed by hand.

There are CG particles, sparks stock footage (if you look closely you can really see the difference, one is more realistic than the other), stroboscobic effects, a lense flare effect I tend to use every time I have to create an impact and that has a cartoony vibe, a part from the ship that flies away even though nobody notices it, smoke stock video footage…

By the way, the CG particles are not Icospheres but Icospheres with displace and noise. This way you get streaks that are not too sharp, it feels more realistic.

3DVF: This shot also has nostalgic vibes, almost as if the ship was a real small-scale model.

That was actually my goal. It also fits well with the subject of the episode, since The Fifth Element, the movie discussed in the episode, features a lot of scale models.

Adding stock video footage and reality CG sparks were quite helpful in that regard. Thanks a lot for your comment, I’m glad I achieved my goal!

In the next part of this sequence [16’01”] I used Star Wars: Episode VIII as a reference, with the Holdo Maneuver that cut the First Order fleet in half. I used a similar lighting approach, with lights all around that turn off so that the only light left comes from the bluish impact.

The shot created by the weapon was supposed to be way bigger at the beginning, and it was created by Alexandre Labedade. He designed this effect and he loves big, bold effects, but in the end it had to be downscaled. Many people would have asked “why didn’t the Captain use this earlier”, or “you could destroy a planet with this thing”. Just like people asked a lot of questions after watching Star Wars: Episode VIII.

An earlier version of the shot, previsualized using Eevee
The end result

The initial idea is still there, though. The enemy is destroyed by a single shot.

I should also mention an editing choice that was quite frustrating for many viewers: you can see the ship beginning to explode, then there’s a cut to another pilot who watches the explosion (there’s even a reflection on the glass panel), then we cut back to the end of the explosion.

This editing choice is actually a technical choice, since it’s easier to create the reflection of an explosion than a real explosion. The beginning and the end of the sequence use two different smoke simulations, but due to the editing you don’t really notice it.

This sequence is quite intersting since it shows that technical constraints sometimes have an influence over the final edit. In the end it allowed us to add this reaction shot within a dynamic scene.

3DVF: Let’s move forward in the episode… There is an atmospheric re-entry sequence with pieces of the ship breaking apart. Again, it’s quite obvious there was a lot of work involved.

For this part of the episode, I used the Explode modifier in Blender, which allowed me to make some parts of the turret fly away. Overall on this sequence I used a mix of Shape Keas and Lattice. the Lattice allowed me to deform and distort things, Shape Keys were used for smaller details.

I also used other tools, such as constraints with Empties animated using curves, and some noise added to the curves. This allowed me to create complex motions, and if you add another Empty besides the first one and shift the noise, it will create some kind of oscillation, something quite natural-looking.

I also used the Hook modifier: combined with a Weight Paint, it allowed me to deform the mesh while controlling which elements would move a lot, a little bit or not at all.

Overall this sequence is therefore a mix of techniques, for example I also used some sine wave curves and some noise to create some periodic motion with a little bit of randomness. There is also a touch of animation done by hand.

I then added particles, stock video footage, and so on.

I also used a few other tricks. For example, I added a bunch of cables and various objects each time a part of the ship was breaking apart. This way, the ship doesn’t feel like an empty shell.

Since I used some “unusual” techniques, there were a few surprises when adding motion blur on a few specific frames. I had to use a few more tricks such as “start on frame”, to tell Cycles to begin processing the motion blur at the beginning of the frame and not between frames, to avoid interpolation issues.

3DVF: Overall, you acted as the VFX Supervisor, you did most of the CG work, and you also acted as the assistant director on this episode. Other artists were also involved, however: how did you decide which parts you would do yourself, wich parts would be done by others? And how did you choose who would do a specific task?

It depends.

I launched a challenge for the BlenderLounge community [Editor’s note: a community of Blender users] back in 2019. You had to create a spaceship, the prizes were 100€ and the opportunity to see your ship in Nexus VI Episode VII. It’s not a huge prize, but we don’t have huge means!

Arthur Chamerois won this challenge, and I’m glad he did: without this challenge, we would probably have ended up buying a CG model on an online asset store, and it would not have been taylored for our needs.

Above and below: two concept arts by Arthur Chamerois

When he entered the challenge, Arthur Chamerois was part of Ubisoft Annecy.

For this challenge, I gave a lot of directions: the size and color of the spaceship as well as visual references. HALO was one of the references, because I love this franchise.

In the end we got all the enemy ships. A few retakes were needed, the spaceship created by Arthur Chamerois was a bit too long and looked too much like a fighter jet: we wanted it to look like a fly.

Above: the original version of the fighter jet Below: the tweaked ship, more compact/stocky

Since the ships have very different sizes and they aren’t always shot up close, it was quite difficult to make sure the smallest ships were visible at all times. During the layout stage it was easy to spot them on a bright brackground, but we knew we would run into issues once everything was added: lighting (especially since many shots are backlit), motion blur, lasers shooting everywhere.

Up Next: the last part of the interview with the escape pods airlock, a few pictures of the shooting, why Romain Toumi chose Blender, a few tips for young artists, and the upcoming Nexis VI episodes!

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