01-22-2011, 12:43 PM
in theory very little. both can do the same job in different way. c4d is easier to learn. Sofimage xsi has the same toolset as c4d, as do all 3d packages with additonal features built for gaming and filming industry. xsi has a addition called ICE, the interactive creative environment, and some really complex tools for manipulation high density models. both can use node based scripting to help build complex interactive 3d scenes. if you're starting out try cinema to understand its limitations then try xsi and spend a long time in its huge 3d arena.