Creating 3D Game Art for the iPhone with Unity Part 3 ppsx

You need to be sure that the topology of your mesh is designed to handle the

animation. In Fig. 2.22, you can see how the polygons were arranged to flow

from the top of the shoulders across the chest and around the shoulders and

biceps. The topology of the chest and shoulders allows for smooth movement

in these areas and will deform well when Tater is animated.

FIG 2.22 The Topology of Your

Meshes Are Very Important, and You

Need to Be Sure to Add Enough Detail

to Allow the Topology to Deform Well

when Animated.

I use the Spin Quads tool often when working out my topology for my mesh.

The Spin Quads tool is great for changing the flow of polygons. For example,

in Fig. 2.23, you can see how I used Spin Quads to change the topology of

Tater’s shoulder and neck.

FIG 2.23 Spin Quads Was Used to Change the Topology of the Mesh.

Topology Is Key

The topology of your

mesh will give you

clues as to where you

need to concentrate

a bulk of your vertex

count. You need to be

sure to provide enough

resolution in the areas

of your mesh that will

be deformed when

animated.

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Creating 3D Game Art for the iPhone with Unity

Spin Quads can also be used to help reduce geometry. For example, whenever

you see edges arranged in the shape of a “Y,” you can use Spin Quads to rear￾range the two polygons until one of the previous selected polygons are spun

into an adjacent polygon. You then select these two polygons and merge

them together to create one quad polygon as shown in Fig. 2.24. It can be a

very effective technique for reducing poly count in your mesh.

FIG 2.24 Spin Quads Can Be Used to Reduce Resolution In Your Mesh.

Merging Polygons and Removing Edges

When creating my models, I didn’t try to build the most optimized model to

start. Instead, my goal was to first capture the shape of the model I wanted

to construct. To begin the optimization phase, I would go through the model

and remove edge loops that really weren’t needed to maintain my overall

shape. Second, I would go through the mesh and merge triangles into quad

polygons. Anytime you see two triangles together, you can simply merge

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Creating Game Objects Using modo