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The s Tars of T he s i ggraph 2012 show floor
By Carey Chico & Mike De La Flor
Every year, graphics gurus and engineering experts congregate in a convention center to talk
about new technologies, techniques, and trends at the annual Siggraph conference. Since
we’re nearing the end of this console cycle, this year’s show focused mostly on maximizing
performance and quality on existing platforms—and making high-end development gear more
accessible to studios with smaller budgets. From the latest on voxels and new cutting-edge
GPUs, to what’s new in the next generation of 3D art software and digital-art peripherals, these
are the trends at this year’s Siggraph.

Unreal Engine 4. effects (such as global a technique called voxel many texture lookups geometry, and are capable
illumination) is often cone tracing (originally into a multiresolution of approximating complex
computationally expensive, developed by Cyril Crassin: volume texture that stores geometry with fewer voxels.
these effects have often www.icare3D.org/research/ directionally encoded voxel Because they are being
been precomputed and GTC2012_Voxelization_public. data. With this approach, cast off of screen pixels, the
baked into the scene. But pptx) to compute global they can use the cone’s limitation is the resolution of
what if your lighting and illumination in real time. opening angle to gather the image. This significantly
world are incorporating In the Unreal 4 engine, light from more directions, limits the time needed to
more and more dynamic voxel cone tracing casts and they can efficiently produce results, and hence
Voxels
elements? Enter Voxel Cone rays off of each screen pixel, approximate distant can be done in real time.
Voxels are three- Tracing. Martin Mittring which travel through the geometry through filtered There are a number of
dimensional pixels. They’re from Epic Games spoke scene volume and which or mip-mapped pixel data benefits to the method that
nothing new—Minecraft is about the increasingly dynamically computes (the far scene gives a larger Epic employs here that help
the most recent high-profile used sparse voxel octree global illumination. sample area with less produce the best results.
game to use voxels—but global illumination in his Where ray tracing uses accuracy), which can then First, the voxels support
they’re making a comeback “The Technology Behind the infinitely thin lines, voxel be used as an LOD system fractional occlusion and
for a very particular Unreal Engine 4 Elemental cone tracing uses “cone for lighting detail. The therefore produce smooth
use in games. Because Demo” talk, specifically traces” as an intersection voxels deliver an alternative cone-trace results. Second,
producing indirect lighting focusing on how they used primitive, which generates representation of the level glossy reflections can

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