The three virtues of a programmer: Laziness, Impatience, and Hubris. – Larry Wall
Legacy:Part 01-Using VertexColoring To Smoothly Texture Static Meshes
Make your mesh
There really are so many ways to make meshes, and one canonly really skim over the surface of all of them in such a breif time, muck around with your 3D software, and figure out a style that suits you, a popular one in 3DS Max, which is not far from the mark with most 3D softwares is to make a basic primitive, such as a cube, teselate the faces, move them to their approximate locations and then subdivide the surface, refine the vertex positions, and recurse the process to your desired level of detail. To do this with max, make your basic shape and then right click it, convert it to an editable poly, from here you can extrude, bevel, etc... the surfaces as well as many other things, you can use HSDS to make your subdivisions as I did in my main tutorial, most people prefer just to use the Mesh Smooth or Subdivide modifiers from the list, HSDS imo does result in a more optimized final product, but there would be many who would disagree.
Paint your vertex colors
In 3DS Max this is done by assigning a VertexColor modifier, you then simply paint your alpha values, I am still fairly new to this (havn't been doing it for more than 48 hours), I choose shades of grey rather than color, the thought did cross my mind though that you could use all 3 colors to determine alpha values of 3 overlaid textures on a 4th base texture, though I have not tried this, and am both not certian if it works, or of the indepth procedure of the how to do side of things.
Make your material, and assign it to the object
From what I understand, you need to do this to make your models import into UTEd, I kind of remember when I first started to import my own content a few weeks ago that I ommited this step, not certain exactly if this was the cause, but the model did not import.
You can also use Multi/Sub-Object materials in 3DS Max to futher increase your palette of texture maps, and assign them by using Mesh Selects, and Material modifiers, and manipulate them with many other modifiers, such as UVW Map.
Export the object
Exporting is a really easy step, the only things you need to make sure you export are the vertex colors, the mesh normals and mapping co-ordinates, the mesh defintion and materials in the object types section, I normally just export everything and UTEd sort things out on its end, set the decimal precision appropriately, I don't think you really need to change this, 1 unit is like a centimeter, and 3 decimal places is like 0.01 milimeters, but if your like me - you'll knock it up just to be un the safe side, I believe UT3 sheds a lot of the detail unless you have a tick in a check box - not certian of this - but I do know it is the case with UV co-ords at least.
Importing the mesh
To easy to warrant any more information :p
Making your material
This would be about the trickiest part in this page, basically what you need to do is use the VertexColor output in the material editor to lerp (linearinterpolate) the two textures, if you hae a third, I believe you also lerp it in such a way that the output of the first lerp is lerp'd with the new color being lerp'd into the lerp - lerp lerp!
An example is given here, though it only uses two textures
After this is done simply apply the material to the mesh, if you are using multi/sub-objects, then apply the multiple materials to the apropraite material nodes in the static mesh viewer.