آموزش The Gnomon Workshop - Direct Illumination in Maya and mental ray

 

With the high degree of photo-realism required in todayandrsquo;s feature films and commercials, traditional computer graphics lighting techniques often fall short of producing the desired result. While traditional CG light sources attempt to mimic real-world light sourcesandrsquo; behaviors, they are generally very simplistic versions that lack the dynamic and physical characteristics of real-world light. In this DVD, lighting artist Fredric Durand demonstrates a variety of methods to improve the overall appearance of direct illumination within Maya and mental ray. This involves not only changing the fundamental way CG light sources illuminate our scene, but also how they help to describe the materials in the scene. This series of lectures address the technical and physical aspects of replicating real world lighting, while also focusing on the artistic aspects of lighting. Initially, the fundamentals of CG light sources are discussed. The Maya spotlight and area light are completely dissected to expose extended direct illumination features and controls for each light source, including light falloff strategies, controlling light color, physical light setups, and light rigging for added control. Rendering using Unified Sampling and setting up a correct Linear Workflow in Maya are also discussed. Next, focus is shifted to specular highlights and the reflection of light sources where topics such as layering specular highlights and setting up reflector rigs are discussed. IES and Photometric light distribution utilities and custom color and light decay methodologies are discussed to provide even more realistic lighting conditions. Indirect illumination methods, including global illumination photons, caustic photons and final gather, are covered next to demonstrate the full potential of direct illumination with CG light sources. Lastly, Fredric demonstrates how to achieve realistic lens effects, specular bloom, glows, glares and atmospheric effects using a combination of 3D and 2D techniques while also highlighting the many limitations of a 3D only approach to these effects. .