Hammerhead Accelerates Creative Iteration with Redshift Biased Renderer

In 2003, Hammerhead opened its first international studio in Seoul, South Korea, dedicated to animation production based on branded characters and stories from around the world. They have produced nine animated feature films so far - the most recent was‘The Boxcar Children’in 2014 with eOne - and specialize in brand extension projects with theCartoon Network, Nickelodeon, MattelandActivisionand other clients.

Their most recent feature film work was for the 2015 movie‘Aloha’, a story set in Hawaii that required the creation of a satellite orbiting high above views of planet Earth below. [Pictured here.] As a middle-sized facility, for such projects Hammerhead plans ahead for speed and efficiency.

Biased Global Illumination

Hammerhead’s rendering software isRedshift, a GPU-accelerated, biased renderer that uses approximation and interpolation to achieve results with relatively few samples, increasing its speed. Redshift supports several biasedglobal illuminationtechniques that enhance realism, including brute force, photon mapping with caustics, irradiance cache and irradiance point cloud.

To render massive scenes with millions of polygons and complex textures that do not fit into the computer’s video memory, VRAM, Redshift uses anout-of-core architecture, allowing the use of regular off-the-shelf hardware. Most GPU renderers are limited to the VRAM available on the video card.

Contributing to this, Redshift will supportgeometry instancingin order to render massive scenes with large numbers of repeating objects efficiently, with a very small memory overhead. Redshift also supportsrender proxies, allowing placement of previously exported geometry in a scene, but loading into memory only at render time. Redshift proxies can be instanced like regular geometry, making it possible to render scenes with billions of instanced polygons.

Faster Iteration

On the ‘Aloha’ project, while the company could not afford a 400-CPU farm to push through as many frames as the project required, instead, Redshift was able to iterate fast enough so that the team could define the production workflow based on both their renderer and on their creative relationship with the project's director. CG supervisorKen Pellegrinosaid, "My supervisor would sit next to me when I was working on the final lighting of a scene, and we could make changes on the fly instead of having to wait until the 4pm review time, while other shots being worked on were rendering.”

One-stepprogressive renderingallows interactive previewing of scenes without waiting for GI pre-passes. They can, in real-time, make lighting and camera adjustments, get a fairly good idea of how it will affect the look of the shot, and make decisions earlier. “We could also do ourpre-visusing Redshift at close to 70 per cent final quality, which gave the director a much better idea of what the shot was going to look like. It was especially useful to have elements likedynamic lightingandtexturesin the images so early on. We could lay out a scene with enough of the final look incorporated, to avoid getting hammered with notes on updates later in production."

More than Real

Redshift's biased rendering approach suits a range of work like Hammerhead’s that demands varying degrees of realism. "When producing VFX, and especially fully-animated pieces, 100 per cent physical accuracy is not necessarily what the client wants," Ken said. "They have a look in mind, and recognise what looks right. Therefore we need to be able optimise render times to turn shots around quickly at high quality for client review. By iterating at a much higher rate when lighting a scene, for instance, I can get much faster feedback if a frame takes only five minutes, compared to 50 minutes on traditional renderers.