R.EYE.R wrote:
I come from Real3D (Amiga) and Lightwave 5.5-9.0 time and always assumed software had its own rendering engine.
Now I am starting poking around ZBrush and Maya and VRay intrigues me somewhat, but I am not entirely sure of the concept.

My past workflow went through modelling a surface -> texturing it -> setting lights -> rendering.
Now with the VRay for example - I don't have to texture the surface at all since it has own materials? Or I don't have to set the lights as it has a series of simulated presets? Or is it simply a "plugin" that uses different rendering algorithm somehow improving rendering speed by simulating diffraction and reflection calculations?

The latter is more accurate.

In the context of Maya (and really in the context of any software that has pluggable renderers) here's how it works:  The renderer is the software that takes all of the information you provide it and creates a "finished" image.  I put finished in quotations because, generally, there is still one more step -- compositing -- which takes a number of images (called elements or passes) from the renderer and produces your so-called final image.

Now.. what is "the information you provide"?  Well.. you've got to give it models (animated or static) that have proper UVs (there are some esoteric cases where this isn't actually required but for now let's ignore them), you need to give it lights and you need to give it texture maps and material properties.

In the case of a renderer like VRay for Maya the material properties can either be supplied using standard Maya Hypershade nodes or you can use the (far superior) VRay materials. You can also use any combination of the two. But the mechanics is still the same.  Build a model, create UVs, make texture maps, create the materials, add lights and render.  This is true for basically any renderer you use in Maya be it VRay, Arnold, 3Delight, Renderman, Maxwell, Mental ray, etc.  Each of the above differs mainly in *how* they get to the final image and what sort of control you have.. but they're all basically doing the same job.

Some renderers are slower than others, some are more memory efficient, some simulate the physics of light more faithfully, some are very easy to control.. they all have various pros and cons.

R.EYE.R wrote:
I don't have to texture the surface at all since it has own materials?

The secret to good materials:

"If a feature is going be used, it's going to be mapped.

I don't use solid colors; I don't use a single roughness value; I don't use a single layer opacity value..."

Mike Verta, via the Maxwell Forum

R.EYE.R wrote:
Still on Maya 2012 and OSX 10.6.8, so V-Ray 3.0 is probably off the cards...

The surfacing is not a big deal, as long as I know where exactly I should be doing it: if I map a surface in Maya and then V-Ray resets it all in render, then what's the point?

Also, which part stores presets in relation to objects/scenes? Separately? So, on loading a scene one will have to re-load all the surfaces each time from V-Ray interface?

vray for maya integrates fully into maya. You do everything in a maya context and then just hit render. Everything is saved in your maya file. There is no vray interface per se. Vray just adds a few more nodes to the hypershade (and possibly a few others elsewhere. I can't remember).