PART ONE

This is the hull of a fantasy ship I've made in Rhino, brought into UVmapper. I turned on the "checker" so I can see how things look: always do this!

PART FOUR

The goal in UVMapper, is to get your UVMap to let the checker fit the object's surface so that a flat image can fit it reasonably well. Not always possible of course, but you can paint imnages to fit distrotiosn afterwards if need. You also want the UVmap to be as large as possible, but stay within square boundaries. You can keep the object in scale, but that's nor always vital for simple things like say, a plank.

  UVMapper will align the UVmap in a variety of ways, as if it was projecting the texture onto the surface in one of several ways:
PLANAR is from front/back, up/down, and left right.
CYLINDER obviously like wrapping the image to a tube, and so on for other map types. You just select what type and UVmapper does it for you.

There are some points though: you do want to SCALE THE MAP when it gives you that choice to keep it in proportion. You also want to keep the map within the square of colours on the map.

  Tips:

• The " = " equal key will spread the selected object UVMap to fill the square as best it can, kind of handy, especially if doing lots of objects you wish eventually to share the same texture for example, pavement slabs. If you have them all fill the map, and select them all you can them adjust the UVmap for all, at one time! Thus one texture/material will fit them all. However, it does lose the exact scaling.
  
• You can split objects up and map them different ways! Just select the polygons using the select by facet tool. This lets you map one area cylindrically, another spherically and so on, to arrange things as you wish.
•  Box mapping is a goodway to split an object up and try to apply differing mapping types to each part.
• You can select by edge, and then use the " - " and " + " keys to spread the object out at the edges, so curving surfaces don't get smeared at the edges, for example, the bottom edge of the hull. That can be a tricky business and maybe best after you pin some facets down, or split the objects UVmap up.
• When working with lotsitems,  hide or drag items off the map, so they don't clutter the screen and allow easier selecting of things. Remember to put them back in the map when finished! ;)
• When you first load a map up, "SELECT ALL" then hide them all using the " [ " key, and then deselect, so your worksurface is clear, and you can work on individual parts from then on, and hide then when fisniehd working on them.
• The " [ " and " ] " keys hide and show selected objects/facets.
•  Be aware that say you are mapping 3 decks of a ship, all to have the same plank texture, you wish them also therefore to be uvampped to the same proportions! So select and map them all at the same time, so it's all in proportion. Sometimes this won't work though, for example on all the railings which spread around, rather than lie in one plane, and you will need to judge scaling by hand
•  Don'/t use the "split" option unless you need the parts to have different materials, for example I don't care much about the inside of the hull, but if you were giving a fancy wardrobe differing textures front and back, you would..
• If a mesh fills the entire map, say by using the " = " key, a texture will fit it completely, for example, you take the front of a cube, map it and hit the "=" key, later on if you apply a standard 512x512 texture, it will totally cover the object. Which is fine if you want that, but you way wish to keep the UVmap in scale so it looks sensible on your model.Again, it can be a process of trial and error. Just save your model with different name, load it up in Vue, apply a material that's easy to judge scaling with, like a checker, wooden planks etc, render, and see what you think of it.
• If you use your UVmap template to paint or collage a texture in Photoshop, PaintShopPro etc, I'd recommend making a layer filled with an appropriate colour, like dark brown, below the actual texture as a "fill".So if you've left any accidental gaps, or missed an edge, it will fill it in.
• You can fit several different parts onto one UVMap, for example, I did this fitting the left and right side of the hull on one map, thus, if you paint a texture, you need less images per model. You often find a UVMap leaves lots of space, you can add other parts in...but you don't always have to especially if you wish to use a simple image on a simple object like a plank.
• You don't have to UVmap every part, again, like the proverbial plank, though you may find making their UVmap's large, but fit within the map square, is good, as your modeller mnay have exported the map very small, or very big and thus textures fit oddly in Vue
  
   There is a lot of trial and error involved in learning this process and there's no easy rules!
  

When you've got the map looking reaosnable, save the model, and if you wish, save the "template" the template is the UVmap so you can paint on ti to get precision, next image shows the hull UV map of the ship, and you can see the deck is UVmapped to.

UVmaps can also be used to create precise specular, reflection or "dirt" maps.