Datasheet

Project: Applying Textures  29
The headphone ear pads can also benefi t from a
custom bump texture. The Pad_L and Pad_R sur-
faces utilize the full UV texture space with a single
UV shell for each surface. Because each polygonal
surface is doughnut-shaped, there is a seam where
the left and right sides of the UV texture space
meet in 3D space. You can locate this seam by
RMB+clicking in the UV Texture Editor, choosing
Face from the marking menu, and Shift+clicking all
the faces that form a vertical column on the far left or
far right side. The corresponding faces are highlighted
in the view panels (see Figure 1.34).
Real-world headphone ear pads are often bunched leather that creates numerous parallel
grooves. Because the UV shell for the pad geometry is square, such bunches must be painted
as vertical black, gray, and white streaks, as shown in Figure 1.35. (When it comes to bump
maps, 50 percent gray leaves the surface unaffected, while high values create ridges and low
values create grooves.) You can create such streaks in Photoshop by manually using the
Brush tool or cutting and pasting from a photo that contains similar vertical features. As a
bonus, you can add horizontal white dashes to replicate stitching that occurs near the pad
edge. For example, Figure 1.35 illustrates a completed texture. Note that a texture need not be
perfectly square to function. In fact, with the pad geometry, it’s easier to fi t in a suffi cient
number of vertical lines when the texture has a greater number of pixels in the U direction
than in the V direction. After the texture is mapped to the Bump Mapping attribute of the
appropriate material, it’s necessary to adjust the Bump 2d node’s Bump Depth and the mate-
rial’s Diffuse and specular attributes. For Figure 1.35, the following settings are used:
Bump Depth: –0.2 (a negative value inverts the bump result)
Diffuse: 0.4
Eccentricity: 0.2
Specular Roll Off: 0.2
Figure 1.33
(Left) Custom color
texture. (Right) Ear
cup rendered with
logo. A sample file
is saved as head
phones-step10.ma.
A finished texture
is included as Ear_
Cup_Color.tga in
the ProjectFiles/
Project1/Textures
folder on the DVD.
Figure 1.34
(Left) Leftmost
column of faces of
the Pad_L surface
are selected in the
UV Texture Edi-
tor. (Right) Corre-
sponding faces are
highlighted orange
in the persp view
panel. This indicates
the seam where the
left and right sides
of the UV texture
space meet.
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