Unreal Development Kit Website now offers downloads of the March build of the UDK, the free software development kit for creating Unreal Engine 3 games. This is accompanied by a new high resolution trailer (you can switch the format to 1080p if your connection/system can handle it) showing off new enhancements, as word is: "Epic recently presented a brand new Unreal Engine 3 real-time demonstration entitled 'Samaritan,' which leverages DirectX 11 support, high-end rendering features, NVIDIA APEX physics technology and other engine upgrades. These new technical additions are now available in the March build of UDK." Epic also wants to remind developers they've recently reduced their share of royalties on commercial games created with the UDK, saying: "Under the new license agreement, developers don’t pay any royalties until their total revenue exceeds $50,000 (US). Beyond that, developers keep 75 percent of each dollar they receive and Epic receives 25 percent." They point to an article on Develop that breaks down how this works in more detail. The March UDK is mirrored on AtomicGamer, and a complete list of new UDK features follows.

Important DirectX features now shipping with UDK include:

• Tessellation and displacement;
• Geometry shaders;
• Multisampled textures; and
• Shader Model 5.

High-end rendering features include:

• Image-based reflections that allow surfaces of any shape to reflect an approximate version of scenes, with varying glossiness across surfaces, anisotropic HDR highlights and anti-aliasing;
• Subsurface scattering (SSS) that simulates the light that scatters inside semi-translucent materials, making character skin come alive;
• Anti-aliased masked materials that super sample the edges of masked and alpha-tested materials, making character hair more look realistic than ever before;
• Deferred rendering with MSAA support;
• Bokeh depth of field providing close to film-quality DOF, with artist-controllable Bokeh; and
• High-quality dynamic shadows from many lights on the environment, such as shadows for point lights and other light sources.

NVIDIA’s APEX technology has also been integrated into the engine and ships with UDK.