With Guardians of the Galaxy arriving on DVD & Blu-Ray on November 24, 2014 in the UK, Trevor Hogg chats with Nicolas Aithadi about the visual effects work contributed by MPC…
“We got contacted along with a number of facilities to create a test for the film,” explains MPC Visual Effects Supervisor Nicolas Aithadi as to how the VFX company became the one of two main VFX vendors along with Framestore for Guardians of the Galaxy (2014). “The idea was to create a Groot and/or Rocket in animation; they would look at them and decide the one they liked the most. We decided to only do the Groot test because that was the character I wanted to do; they liked it and asked us to do him for the film.” Concepts art was produced by Marvel showing what the CG humanoid tree bounty hunter would look like. “If you compared the Comic-Con Groot with the one in the movie you will see a big difference. The character evolved a lot. It was a combination of us, James Gunn [the director] and Marvel coming up with ideas which resulted in specific changes. James was adamant that people should fall in love with Groot and Rocket. If you look at the original Groot, he’s more like a tree. We decided to humanise Groot.” It was important to strike the right balance. “We didn’t want Groot to look like a block of wood turned into a guy. We decided to build all of the branches as individual objects bundled together and they all moved and slid with each other on the body.”
“If you have a fleshy character what gives you the detail in the body would be muscle and skin,” observes Nicolas Aithadi. “By having all of these branches moving independently it would replicate the effect of muscles moving around. It would give you the impression that he is alive. We had to step back because at some point it started to look gross because these little pieces of wood looked like veins. The first time we rigged the face it felt like a rubber mask. It’s what they would have done in the 1960s. If you looked at the face we decided that the area between the eyes and the mouth as well as the eyelids around the iris could be bendy. Everything else we broke it down into small plates so when he was neutral you didn’t see anything. As soon as he was moving you could see the plates sliding on top of each other. When he was angry which happens a couple of times in the show those plates were moving a lot and emphasizing the monstrosity of the character because his face started to look spiky, sharp and dangerous. It’s a combination of all of these little things.” Animation had to be devised on how Groot would move. “Greg Fisher our animation supervisor creating interesting tests where you would have fluid human animation. Then Greg did the Groot version where his body would stop moving for a couple of frames and he anchors himself in the moment which gave a weirdness to the motion that James loved.”
A key facial element had to compensate for Groot having a vocabulary of only three words. “We worked a lot on the eyes because Groot is limited with his dialogue,” states Aithadi. “People needed to understand what he meant with just, ‘I am Groot’ and his facial expression. We looked at real eyes everywhere and we were trying to understand why those eyes looked real and you could get lost in them. The first thing was to make the eyes imperfect in some way. The killer in computer graphics has always been perfection. It’s always too perfect, clean, straight, or round. The face was made of wood and the head had to be symmetrical but we gave the trajectory of the eyeball a slight shift. Usually, we add delays with eyelid movements when we blink but on this one we created delays in the way eyeball was moving as well. The other thing that we did which was a more technical exercise was we had to create more detail than we had ever done. If you zoom on an iris you can see all of the ridges that look like aerial photography of mountains. We displaced those. When Groot was lit we would create shadows inside the eyeball. We had this turntable of the face and you could spend 40 minutes just looking at his eyes.”
Five different versions of Groot appear in the space opera. “The Groot Cocoon was the hardest of all of them,” remarks Nicolas Aithadi. “On-set they built a cocoon which looked like a motorcycle helmet made of wicker and they had the actors in there and the camera going through. We started by matching the physical cocoon and rebuilding it as a full 3D object while they’re doing the show. We wanted the cocoon to continue moving even when it was complete. We decided to replace the real one so it was all CG. We had a couple of shots where Groot is extending an arm or some branches where we setup a rigging so we could have branches extending but it wasn’t working. We looked at time lapse videos of a stuff growing and one thing that makes things look like they’re growing is gravity. While they’re growing they’re more attracted by the ground and that’s when you get this weird jiggle. We added some of that and right away it looked like a branch growing.” Groot unleashes spores to illuminate the interior of the Dark Aster. “We created some spheres which were moving around and James felt that they were boring. We looked at references online and ended up with something that looked more like a sphere with hair. As it tumbled through the air the hair wouldn’t be bioluminescent just the body; it would be there to protect the chute. We simulated those and James liked them.”
Groot impales two rows of soldiers within an enclosed space which was given the previs treatment which was longer than the sequence which appears in movie. “We had the shot where you see the hand coming together into a spear shape,” states Nicolas Aithadi. “We extended the fingers a little bit so you would feel his arms start to stretch. By the next shot the thing has already been created. We attached a different geometry on the arm and extended it. The balance on this one was the PG-13 rating. How violent and graphic could this sequence be? In the beginning we discussed the idea of having yellow blood but the problem is when you don’t have light is that it still looks like blood. It needed to be funny not gory. We add some more CG stuntmen to make the shot more interesting.” Groot Tiny dances to a tune performed by the Jackson Five. “Our favourite shot! What happen was that James shot himself doing the dance because he didn’t want Groot to dance like a dancer; he was suppose to be more like a happy in the moment. We added the tempo because Groot needed to move well with the beats of the music. A great touch from Greg Fisher was when Drax [Dave Bautista] turns around Groot stops and has a nice little eye movement. When we first showed this shot to James and the Marvel gang we got a big laugh. I went to see Guardians of the Galaxy in the theatre and people laughed so much at that moment it made me proud.”
The opening setting was created by MPC. “Morag is one of my favourite environments because it was the most textured, vibrant and is visually beautiful,” remarks Nicolas Aithadi. “It had a set. We started with reference that Stephane Ceretti [Visual Effect Supervisor] shot for Marvel in Arizona and Egypt. It was a mix between those two environments. We wanted to get something more interesting in the frame so Marko Ljubez, our Environment Lead, came up with the idea of these gigantic arches, spires and a pointed sharp mountain range. We put that idea to James and Stephane, and they went for it. James is all about contrast and likes when you see something nasty, ugly and aggressive to balance it with something beautiful. We had this dark and moody planet surface with this beautiful reddish sky and that was the world we created for that. The other interesting and complex things that we had to do were the geysers which are everywhere. In the background of every shot there are one or two geysers going off. At the end when Peter Quill [Chris Pratt] escapes he is taken by a gigantic geyser. That geyser was technically challenging because of the number particles which was about 20 billion. We had to make it work in about five or six shots. The rest was technically straightforward. It was an artistic endeavour which was the great thing about it.”
“Xandar is 24 kilometres wide so it is enormous city,” remarks Nicolas Aithadi. “We started with a couple of pieces of artwork from the Art Department which was representative of some views of the city. We had the Google Map view which was showing us that the layout from the sky that’s when we realized that the city was shaped like the Nova Corp logo. We realized that we needed several versions of the city: a low resolution version of that we could see during the final battle from 10,000 feet in the air, a version that we used as the background for the mall sequence where Gamora [Zoe Saldana] and Quill meet for the first time, and a high resolution version of for all of the shots that take place on the ground. It was a lot of work. We started with the low resolution version which would be used in most of the shots. The Art Department sent us the geometry and we laid out the whole city from the sky. There are an enormous amount of trees in the city; that is when we decided that we wouldn’t be able to render with RenderMan. We had to switch to V-Ray for the city at that point which was another challenge because we don’t use it usually.”
“Once we had a whole city established we had to create the city that is seen close-up,” states Aithadi. “We needed to create an architecture that would be recognizable to people but at the same time make it look like not something we would find on Earth. We went to Google and typed ‘weird buildings’. Some of the weirdest buildings we found were in Singapore, Dubai and Shanghai. We organized three trips. I went to Singapore with the visual effects supervisor. We organized a helicopter shoot of the city and two photographers went around taking pictures of the buildings. In Dubai and Shanghai we did the same thing. We brought all of these images back plus ones of other buildings from around the world and created a library of buildings. The buildings that were approved by James serve as an inspiration. The Environment Department created concepts using elements like a roof or window shape or a staircase and created a new building. These buildings would then be modelled in high resolution and laid out through the city. We would dress the buildings with props like chairs and tables. We created floors for every story. We added greenery to the balconies, terraces, and roofs. We created about 60 buildings that way. We scattered around only in the shots where we needed high resolution buildings. For background and other parts of the city we put the lower resolution buildings we had for the aerial shots. We thought it would be cool to create marinas with boats so we created these weird alien boats. Then we created a crowd simulation of life moving around the city. It was enormous work. The city took 9 to 10 months to create which was pretty much the whole project.”
“The final battle was the most challenging thing for MPC in Guardians of the Galaxy,” remarks Nicolas Aithadi. “It is a long sequence. We had to build all of the spaceships. The Dark Aster which was the biggest ship in the film. It was 12 kilometres long. We had a shot starting from a wide shot and finishing as a close-up which is the worse kind of shot you can imagine in CG because you need to make detail all the way through. The model was a big undertaking. We started off with 18 billion polygrams. We had to stop because it was becoming unmanageable. We finished up the details in matte paintings for the extreme close-ups. The Milano had the same kind of challenges. It was about the size of a 737 which is quite big for a spaceship and had to be build with a level of detail which was quite impressive. We built the outer and inner structure because we had flaps opening and closing. On-set they built a cockpit and every time you see it outside we had to extend it with the wings and body. We did the Starblasters which are the Nova Corps yellow ships to a high level of detail and the Necrocraft was built in several resolutions because we had the hero and there were a lot of shots where they were part of a crowd simulation. Some of the biggest shots had 40,000 Necrocraft. There are hero explosions which are all of the explosions that are in the foreground of the shot and then we had the library explosions which were all of the explosions that are in the background. We couldn’t simulate all of those on each shot because one of the shots had 7000 explosions in there. We had a system if one of the ships was hit by a tracer it would explode and trigger a library explosion; that’s how we choreographed the effects.”
“The black fire was quite complex,” notes Nicolas Aithadi. “We were doing it between a couple of companies. One thing we knew from the beginning was that there would be purple smoke and fire swirling around. We knew that there would be some affect on the skin of Peter Quill and then Framestore did the sequence in The Collector’s Lab where Carina [Ophelia Lovibond] grabs the orb and destroys the whole thing. They created these fireballs with smoke trails flying around. James and Marvel asked us to put it in our sequence so we had to add that element to our black fire. The smoke needed to be choreographed, timed, rendered and simulated. It was a lot of things. When Quill is affected by the orb you can see the energy going on the ground which causes purple cracks. The same thing happened to Luma Pictures because they liked the effect. James wants continuity so if he sees something in one shot he wants it to continue into the next shot. It’s difficult when you deal with effects particles to be so strict with continuity. We were cracking the skin in on shot, that would carry onto the next shot in the same place and it would grow; that’s what made it quite complex. The funny element in that shot was Rocket because all of those characters are burning from the inside out, their skin is cracking but Rocket is made of fur. When we got the Rocket from Framestore we had to match it. We made sure when we were applying the groom that we would keep control of it. We didn’t want to send Rocket back to Framestore and ask, ‘Can you change the groom and give it back?’ We added the ability to animate the groom in that sequence. We created an animation where the groom is receding to the skin and was crumbling at the tip. It looked like singed hair and that would propagate along the arm. We showed that to James, he liked it and that’s what we kept for the film. It was cool.”
Guardians of the Galaxy images and video © 2014 Marvel Studios/Walt Disney Pictures. All Rights Reserved. Courtesy of Marvel Studios, Walt Disney Pictures, and MPC.
Many thanks to Nicolas Aithadi for taking the time for this interview.
Concept Art from Guardians of the Galaxy
Shared Universe: Stephane Ceretti talks about Guardians of the Galaxy
Engineering Danger: Sony Pictures Imageworks & Guardians of the Galaxy
Cosmic Landscape: Method Studios & Guardians of the Galaxy
Knowhere to Go: Framestore & Guardians of the Galaxy
Trevor Hogg is a freelance video editor and writer who currently resides in Canada.