3D Animation for the Raw Beginner Using Maya

341

Chapter 13

The UV Texture Editor

W

   C 5 that before we create a 2D texture we must choose between the

settings Normal and Projection. For the examples in this chapter, we focus on textures

made by rst clicking the Normal radio button on the Create 2D Textures tool in the Hypershade.

THE (U, V) SURFACING PROBLEM

One of the more tedious problems facing the 3D animator consists of putting textures on

irregularly shaped surfaces. e crux of the problem is that the (u, v) grid on the surface of

a model can stretch over geometry that varies signicantly in its relief and, as a result, the

density of vertices can also vary dramatically.

Consider the Moai wireframe in Figure4.66. e model was craed out of a polygon

cylinder by extruding and rotating faces, and by pulling on vertices, edges, and faces.

Denser geometry was added to smooth various angles on the model, in particular, along

the bridge of the nose.

A checkerboard texture has been made by going to the Hypershade and selecting:

Create → 2D Textures → 2D Projection

Rather than creating a texture immediately, we clicked on the 2D Projection radio but-

ton. en we created a Checker 2D texture. Still in the Hypershade window, we selected

the Textures tab on the top right of the window, and clicked on the square icon labeled

“projection” that was created when we created the checkerboard texture. is pulls up

the attribute editor of the Maya object that controls the laying down of the texture on

an object.

We selected the projection tab in the attribute editor, and went to Proj Type and chose

cylindrical. e result of applying this texture to the Moai is shown in Figure13.1. You can

see that the squares of white and black have been badly stretched out of shape, and as a

result, the material is placed very irregularly.

To help manage the dicult job of laying down a texture, there is a special window in

Maya called the UV Editor. To use this capability, however, we need to rst select:

Create → 2D Textures → 2D Normal

342 ◾ 3D Animation for the Raw Beginner Using Maya

A PLANAR PROJECTION OF A NORMAL FILE TEXTURE AND

USING THE MOVE AND SCALE TOOLS TO ADJUST IT

Figure13.2 shows the rst cut at putting a le texture on a rectangular polygon plane.

is texture was created with the Normal radio button selected. e image has a black

background with lettering that has a ramp texture on it. What we see in Figure13.3 is what

appears if we select:

any Main Menu → Window → UV Texture Editor

e white horizontal line shows us where the le texture is being cut o.

FIGURE 13.3 UV Texture Editor with plane selected.

FIGURE 13.2 File texture on a plane.FIGURE 13.1 Checkerboard Moai.

The UV Texture Editor ◾ 343

In Figure13.3, we have chosen:

UV Texture Editor → Tool → Move UV Shell Tool

is is a 2D move tool that works on the (u, v) surface of the plane. In Figure13.4, we have

used this tool to shi the texture upward on the plane. e resulting render is shown in

Figure13.5.

Using the Scale Tool in the UV Editor

In Figure13.6, we have added a second plane and applied the same texture to it. e result-

ing render is shown in Figure13.7. On the top plane, the texture largely misses the mark.

In Figure13.8, we see why this is true: note the position of the white line. In Figure13.9, we

have hit the R key and this has changed the move tool to the scale tool, and again, we see

that this tool is a 2D tool. Another way to get to this tool is to choose:

UV Texture Editor → Tool → Smooth

UV Tool

(We can go back to the Move tool by hitting

the W key.)

In the UV Texture Editor, we rescale the

way in which the texture is laid down by

using the Scale tool, as seen in Figure13.9.

Notice that we are adjusting the (u, v) grid

and not the texture. So, scaling the grid

FIGURE 13.4 e UV Texture Editor move tool.

FIGURE 13.5 New render—aer move.