Giant CG monsters and devastating destruction scenes hit the big screen back in April in Brad Peyton’s summer blockbuster, Rampage. With the tagline of ‘Big meets Bigger’, the team at Hydraulx knew they would have their work cut out for them to deliver all the complex CG needed. Based on the classic 1980s arcade game by Midway, Rampage tells the tale of primatologist Davis Okoye, (played by the current king of the box office, Dwayne Johnson) who teams up with an albino gorilla called George. After George grows into a creature of rampaging size, he and Davis team up to stop another two over-sized monsters from destroying Chicago.

With fifteen years’ experience and having worked on titles such as Constantine, 300, Avatar and the Avengers, Hydraulx Visual Effects is no stranger to creating demanding CG, but for this project, there was limited time to complete the work. Hydraulx was tasked with producing a huge range of shots - demanding a complete range of VFX techniques - and with a tight schedule, they decided to explore GPU rendering with Redshift.

“We started Research and Development in August and started getting plates a couple of months later. By December, we had a more polished pipeline set up and we felt confident that using Redshift would be a successful choice in completing the work,” says Bill Kunin, VFX supervisor for Hydraulx on Rampage.

After months of exploring the possibility of adopting Redshift into Hydraulx’s pipeline, the lighting department got to use it. “I worked closely with our modeling supervisor - Stefan Schneider, lighting supervisor - Tulio Hernandez and current lead lookdev - Daniel Veder during the adoption phase,” says Chun Seong Ng, CG supervisor at Hydraulx. “Once Redshift was ready, we pushed it to the rest of the lighting department to work on the shots that we needed the most.”

As well as pipeline integration, the speed that Redshift offered proved invaluable, specifically in the early scenes in the film which are set in and around a space station in Earth’s orbit. These shots involved not just the creation of a photorealistic space station but the integration of complex creature work as well. These shots were a key reason why Hydraulx had been looking at Redshift. “Aside from the main actor and some minor on set build, all the rest of the sequence (exterior space station, background digital double, creature work and 90% of the interior of the space station) was all CG,“ says Chun. “I don't think we could have used our previous CPU-based rendering solution to finish the shots that we needed, it easily would take five times longer to handle a similar setup.”

Faster scene manipulation

As the artists worked more with Redshift they realised that the ‘just hit the render button and wait’ approach offered by CPU rendering is very limited and that GPU rendering can really benefit artists creatively, as they have more chances to refine their craft.

“The opening shot alone is over a minute long so the speed gained by using Redshift allowed for more revisions to be done in less time,” Bill explains. “We knew right away that the major increase in speed looked great as well. Once we were able to dial in a great-looking render of the space station, it was clear that Redshift was the way to go.”

Redshift did a great job at showing off the Hydraulx artists’ meticulous hard-surface modelling work, and the team were also able to easily use it to their advantage for the complex creature work - thanks to the GPU renderer’s full suite of production-ready render tools. Just as with the photoreal hard-surface work, it was critical that Rampage’s creature work was exemplary in order for the CG monsters to be believable.

“There was plenty of back and forth on what could be potentially useful to the show during the Rampage Research and Development process,” says Chun. “For example we used rsProxy on the creature fur and digital double's hair. It took us some time to figure out the workflow, but once we had figured it out, we never looked back. We are talking about saving loading time, faster scene manipulation; without the need to deal with a huge cache file.”

GPU and CPU powerhouse

Another advantage of using Redshift is that it offers amazing speed and power using off-the-shelf software and hardware. For the artist workstations, Hydraulx invested in powerful Nvidia GPUs and for final rendering, Hydraulx created its own GPU render farm consisting of machines with up to four GPUs each.

This meant that the existing Hydraulx CPU infrastructure was freed up and Hydraulx was quick to take advantage of the new opportunities this offered. “Since we were able to render on the GPU, it created a positive scenario that our CPU farm could focus on simulation and compositing,” Chun explains. “With this new parallel process pipeline, it allowed shots to have a faster turn around.”

Time-saving management

For the compositing work, Redshift worked hard and was really efficient at managing everything. “We generated tons of puzzle mattes with object and shader IDs along with all other AOVs, so compositors would have full control of the whole scene in Nuke,” says Chun. “We are looking forward to the deep output hopefully being unified along with other AOVs in a future release as well as incorporating Cryptomatte into our next show”.
[Note: Cryptomatte is now supported in Redshift for Maya with support coming soon to other host application plugins.]

As Rampage stomped across cinemas in the spring, Bill and Chun have had a chance to reflect on how their first job with GPU rendering went. Chun reflects: “It is always a challenge to adopt any new software to the pipeline, I would say we were able to incorporate Redshift quicker than we originally thought.”

Bill recalls the moment that he knew Redshift was the right choice for Rampage: “The space station was the opening sequence in the film, and that made it especially important to get the space station looking photoreal. The audience had to be drawn into a film relying so heavily on visual effects, so it was critical to get that right. When we finished, it was obvious that Redshift was instrumental to completing this heavy and complex sequence”.