Dividing a Character
The most efficient way to texture a character is to divide it up into areas whose shapes lend themselves to a particular type of projection. For example, an arm could either be treated as a cylinder, or if divided lengthwise, could use two planar projections. The idea is to approach the mapping procedure with a strategy.
Here is what to look for when choosing how to break up the character:
Splitting the geometry up will make it easier to apply the initial UV projections to the character. With these in place, we can then go in and tweak the UVs individually to reduce any undesirable stretching and overlap.
We will now begin working on Kila to show how best to divide her. No mapping will be applied at this stage.
Load the file called Kila_DeformTest.mb.
It's been a while since we looked at the Kila model because we have been working on Grae. Take this opportunity to have a fresh look at the model, making sure you are happy with it. When you're ready, we will begin by examining the torso and arms.
Torso and Arm Preparation
Kila currently only has one-half of her upper body; the entire right side is a mirrored instance. We're going to delete the instance and create a mirrored copy of the left torso for her right sidebut first we will extract her arm. We do this because although we want to map then entire torso, the mapping for her left and right arms can initially be the same, so we only need one arm to exist at this time.
We now have a complete torso that is almost ready for mapping. There are two ways to approach this area:
Planar mapping seem to be the best option, so let's now split the torso in two.
The front and back are now separated and prepped, ready to be mapped.
We will apply cylindrical mapping on the arm, because the shape is almost cylindrical and it will give us an opportunity to see this form of projection demonstrated. Alternatively, you could apply the same technique that we used for the torso, as we will with the legs later. The hand, however, will need planar mapping to both the top and bottom, so that we can apply a different texture to each side.
The torso, arm, and hand are now ready to be mapped. Let's continue down her body now and work on the legs.
For Kila's legs, we can adopt the same technique we used on the torso. Her jeans will have a seam that runs down the outside and the inner leg; this can be used to disguise the UV seam.
As you did with the torso, select the front faces (Figure 8.10) and Extract them.
Figure 8.10. Separate the front and the back of the legs.
Shoe and Belt Division
Continuing on, we get to the shoes. Both shoes will be mapped the same, so we can delete the one on the right for now, and duplicate the left shoe once mapping has been applied.
There are a number of ways you can approach the shoes, depending on the amount of detail you wish them to have.
Separate the sides, top, front, back, and bottom (Figure 8.11). We will apply planar mapping to each area later.
Figure 8.11. Divide the foot into specific areas.
Leave the belt intact, since it was created from a basic cylinder that has not been altered enough to destroy its initial mapping coordinates.
With separation of the main body completed now, let's see what needs to be done to her head.
The main head will be fine as it is; a simple cylindrical or planar map will work well here. So let's concentrate on the inner mouth, along with her eyes, teeth, and tongue.
The inside layers of Kila's hair were initially made from individual strips of polygons. Therefore, this part of the hair should retain its basic mappingif we texture one strip with particular mapping coordinates, they will exist in the other strips.
Using this method will save texture space and, since the inner layers are not fully visible, we should be able to get away with repeating the texture. If, on the other hand, the texture looks obviously copied, we can apply a cylindrical map to the layers.
The outer layer of hair is a different story. No usable mapping exists on it because we have drastically edited the topology. But we only need to do a couple of things to prepare the hair.
Kila is now prepped and ready to be mapped. Clean up the geometry by deleting the history, and save the file as Kila_Divided.mb.
Grae is a more unique character than Kila, but a lot of the same principles will apply. We will now take the same steps with the Grae model, getting him ready to apply UV mapping.
Start by loading the file named Grae_DeformTest.mb. As you did with Kila, take some time to check the model for any last-minute changes.
We will initially hide the wings and concentrate on the main body of Grae.
You may be thinking that we could delete a wing, mirroring the other one across. We could do this with ordinary wings because the mirroring would not be obvious. However, Grae's wings are made up of tendrils and should not look identical. What we can do is leave the wings until last, applying them to a separate texture page. Then we can judge whether we have the space to map both separately.
So for now, go ahead and divide up the body.
With the wings hidden, the first area of Grae's body that stands out are his legs. Looking back to our concept drawing, we can see that the upper thigh sections differ in surface design and thus will each need separate mapping. The lower legs, however, are the same, which allows us to use identical mapping techniques.
The lower legs can be cylindrically mapped, leaving the upper thighs to be mapped with the torso, so let's look at that area next.
Let's begin our work on the torso.
Because the upper and lower teeth aren't physically connected, you can simply go to Edit Polygons > Separate to detach them.
This is all we need to do to the upper body area for now, so now let's edit the arms.
Start with the left arm.
Grae is now divided and ready to be mapped. Save the file as Grae_Divided.mb.
With both models prepared, we can move on to apply mapping to Kila and Grae. We will use tools already mentioned in this section, as well as get our first introduction to the UV Texture Editor.