Art of Illusion doesn't export to .X, but it exports to .obj which can fairly easily be converted to .X, it has a procedural texture designer second to none, and it has a great built-in renderer, almost as good as Povray!
Wings 3D also doesn't export to .X, but it exports to .obj as well (also .3ds and a number of other formats) and has an insane number of commands for working with polygon meshes.
Right now I like to make objects in Wings, then export them to .obj and load them into AoI to put on textures and do the final render. Here's an example:
BTW, I think what you're looking for is a MODELLING program - a renderer is what produces the picture on the screen
Re: Rendering Programs
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