Senior Digital Artist Jens Kafitz gives an inside look into Animal Logic's environment lookdev and texturing for the 6 minute Coca Cola short.
In early 2011 Animal Logic started development on a short movie for Coca Cola to relaunch their iconic polar bears from the 1993 animated commercial. This was part of a bigger campaign that included various commercials, some of which debuted during last year's Super Bowl with great success.
In January of 2013, Coca Cola released the 6 minute short film, produced by Ridley Scott and directed by John Stevenson (Kung Fu Panda). The short follows a family of polar bears - Kaia, Zook, Kaskae and Sakari - on their adventure and is meant to introduce the public to the characters of future ads.
Deep Blue Ice Look Development
"The environment had a few challenges for us" says Senior Digital Artist Jens Kafitz. "While there were very few materials - snow, deep blue ice, a frozen lake and mountains - it was all part of one big set and seen both close up as well as far away. Our shaders had to cater to that and once we were in asset production, shader changes across multiple assets and shotfixes should be avoided". That meant that they had to come up with solid shaders and workflows quickly to ensure consistency. Under the supervision of the Art Director and Surfacing Supervisor, Jens started working on a series of tests to find the right look for the ice and snow.
"Animal Logic had previous experience in dealing with snow and ice covered landscapes mostly from the 2006 animated feature "Happy Feet", so we knew what was required. But our shading pipeline had changed quite a bit since then and especially the blue ice was a challenge so my supervisor had me focused on that during our tests. Two things had to be solved: the color shift from white to blue and green towards the core of the object, as well as the large cracks that run deep through the entire volume of ice."
"We decided early on that we wouldn't try and fake the effect of the color shift, but tried to find the correct subsurface scattering settings that would give plausible results on objects of any size - from a small ice boulder to a cliff the height of a glacier. We ended up using Autodesk Mudbox to create displacement maps which, plugged into a parallax shader, were driving the scattering."
"The Texture Artist would load in an asset and start hacking away at the model until it was just a skeleton of the original. The deeper the artists carved into the object the more blue it would get while rendering in those areas, with the deepest holes getting a sapphire tone. Areas of the model that were left untouched during sculpting and therefore close to the ice surface, would be more white in rendering. Occasionally we would multiply or screen high frequency maps over the extracted displacements to give subtle shifts in depths even when close up."
"In order to have this effect not be static the resulting displacement map out of Mudbox was plugged into a steep parallax shader that had been developed at Animal Logic earlier. Parallax Shaders are something primarily used in the game industry and give a depth effect to an otherwise flat surface. Different from just a normal or bump map, raised areas can occlude each other."
"An additional layer of complexity in the scattering was introduced by a series of mostly white fissures that were meant to run through the top layers of the ice. One requirement for them was to be easy to art direct while still being quick and easy to create for the texture artist."
"To make things easier we created a library of fissure maps with different shapes. Again we resorted to Mudbox for this by utilizing Mudbox's Tileable Plane. For the samples shown below, I turned on the Screen Distance Viewport Filter and used the Knife and Smooth Tool to carve into the plane from a Top view. Within minutes I would have nice tiles closely resembling the look of the ice cracks in the reference. The result would get exported as a handy 2k or 4k 16bit map using the Export Screen function and used as Stencils in a regular Texturing workflow. The finished fissure map sets would again be used in combination with our in-house parallax shader to drive subsurface scattering to simulate depth in the ice while a leveled version was used on the outside surface."
"Snow has been done many times and it is not really a secret how to get it right. Still there are a few things one has to keep in mind. Obviously, as was the case with the blue ice, the correct scatter settings and diffuse contribution had to be found that would give a slight bluish tint in recessed areas. Another consideration was the greyish look snow tends to have from certain angles. The stylized sparkling of the snow was an in-rendering effect with a custom shader but further enhanced in comp."
Jens continues, "While the fine grain of the snow was applied in the shader using tileable maps, each asset got a full sculpt pass by the Texture Artist to get both large and medium sized differences in snow height. Funnily, we found that NASA satellite images of cloud formations make excellent large snow detail. Their shading makes for almost out of the box displacement stencils and when they are over oceans, you get a free key out of it as well."
"We also sculpted in 'high traffic' areas by creating stencils for the polar bear feet and scattering them randomly. Interactive foot prints were coming out of a precalculated shader setup based on shadow maps and then reapplied as displacement."
"All sculpting on the texturing side was done in Mudbox and extracted as 16bit displacements, as it proved to be the most efficient tool for the large polycounts we needed on a single surface. Distribution of snow was done via simple, fairly lowres masks in the shader with an added procedural multiplied in the soft areas of the masks to get fine breakup on the edges."