In this video taken from our "Rendering with SOFTIMAGE|XSI v.II: mental ray" training product, we will get to see how to use the new irradiance particles indirect illumination algorithm and combine it with image based lighting using HDRI rendering. This technique allows us to use the environment sampling feature of irradiance particles to render a photo-realistic scene by using only a High Dynamic Range Image and take full advantage of this highly optimized rendering method.
http://i3dtutorials.com/tutorial/55\_irradi...-hdri-rendering
