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UV mapping a car with Lightwave
Also Available In Microsoft Word Format 'Click to Download'

I would just like to point out before you read this that I’m sure there are many ways to do
the following but this is just the way I found most useful, but I’m always open
to suggestions.
In this Tutorial we will be creating a UVmap as a reference to creating
Decals/ logo’s etc for a Pontiac Firebird as above.
The first thing you'll require to follow along is
a small LScript called ‘Great Box’ The Great Box script is no longer available but you can download it here for the use of this tutorial. (Great Box Script)
I always split my models up into layers, I find that this helps with any
adjustments that need to be made and also it helps with quick updates when
rotating the object in the perspective view, an object like a car with full
interior can soon slow the best of systems down if kept in One layer and
perspective set to full Textured Wireframe. Just for reference I have my layers
set up as follows:

Firstly we need to setup the ‘Bounding Box’ using our GreatBox LScript. Add
the LScript using Utilities / Add Plugins. When complete select all layers plus
an empty layer, mine is layer 17, then activate the ‘GreatBox LScript’, mine is
found in Utilities / Additional / GreatBox. This will create a bounding box with
equal dimensions based on the longest side of your object, in our case from
front to the rear of the car, this of course being the longest measurement.
Now select the bounding box layer only, select all polygons next select the
Bevel Tool (b) in the numeric window leave all settings at their default of ‘0’,
accept these settings then press the space bar to drop the tool. This has now
bevelled our box. With the polygons still selected press the Del key to delete
them then press ‘m’ to merge all points which will now leave you with a box made
of Two point polygons.
Now to start with the UVmap. Activate Layers 2 (Boot) and Layer 17 (Bounding
Box) Select the top Polygons on the Boot and all polygons of the Bounding
Box.

Click the ‘T’ button in the bottom right hand corner and select new, in the UVmap
options window change the ‘Texture Name’ to CarBody_UV, or whatever you wish,
set the map type to ‘Planer’, Subpatch Interpolation to ‘Subpatch’ (If you leave
this option at it’s Linear default you can get some distortion of the map due to
it being a Subpatch model). Set the Axis to ‘Y’

As you can see the boot keeps its scale in relation to the bounding box area
rather than being distorted and taking up the whole UV area.

Next activate layer 9 (Bonnet) and layer 17 (Bounding Box), select all top
polygons of the bonnet and all polygons on the bounding box, click the ‘T’
button select New and in the UVmap window options window change the settings as
before ‘Texture Name’ to CarBody_UV / Planer / Subpatch / ‘Y’

This will obviously create your UV texture for the Bonnet and again it will
keep its scale intact. If you now select layer 2 (Boot) and layer 9 (bonnet) you
will see that the Bounding Box has not only kept the boot and Bonnet to the
correct scale but also the correct position in relation to the car model. This
doesn’t mean that you can’t change them if you so wish and when we come to the
doors we will have to.

Next the doors. Select the polygons on the outside face of Layer 6 (Door_NS)
and again all polygons of Layer 17 (Bounding Box)

Click the ‘T’ button and change all Options to the same as before except
change the Axis to ‘X’. As you can see the door doesn’t line up with the car
outline so a few adjustments need to be made.

Firstly with only the Door_NS layer active select all polygons in the UVmap
window and rotate 90deg then drop the rotate tool by pressing the space bar. If
you look at the door closely you will notice that it’s upside down. This can be
cured by going to Map / Flip UV’s and in the options window select ‘Flip U’ only
and click O.K this will flip the door on its ‘U’ value and consequently correct
its positioning. This will not work if you have any other window active.

Now activate layer 2 (Boot) and Layer 9 Bonnet then with the move tool,
realign the door to its correct position.

Now select the polygons on the outside face of layer 5 (Door_OS) and again
all polygons of Layer 17 (Bounding Box) .Click the ‘T’ button and change all
options as used for Door_NS. Activate Layer 5 only (Door_OS) and select all
polygons in the UVMap window and rotate the door 90deg and as before activate
layer 2 (Boot) and Layer 9 Bonnet then with the move tool, realign the door to
its correct position.

We now need to go through the same routine with the rear wings as we did with
the doors and you should end up with something close to the following but making
sure that the doors align to the rear wing otherwise the logos, if painted the
full length as in our example, won’t line up.

There aren't any decals or logos to go on the front wings but should you want them
just repeat the same procedures as we did for the doors and rear wings,
also, being a convertible, the stripes we will be creating for the Bonnet and
boot won’t be following onto the roof, but if you should have one on your model
just follow the procedure as we did for the Bonnet & boot. Its worth noting
that you can move any of the parts that make up your UVMap because the point of
this exercise was to keep all parts to scale not necessarily in the correct
position. Here is the completed UVMap that I created for the Pontiac.

Notice that I’ve moved the boot up to fit in the rear bumper which has a bump
map texture to be applied to it, the same goes for the head lights which also
has a bump map for the Pontiac logo . This brings me neatly to my next point
which is that this UVMap can also be used as a reference for creating the Bump
map textures, should you require them, and any other texture map that may be
required, One UVMap used for the whole car, sounds good to me.
Here’s my finished texture map painted in Photoshop, I’ve left the UVMap
layer exposed so as you can see the position of the decals.

Thanks’ for your interest in this small tutorial and I hope it’s been of some
use, if only to give you some ideas.
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