Page 153 - Enhancing CAD Drawings with Photoshop

4386.book Page 136 Monday, November 15, 2004 3:27 PM

136 CHAPTER 4 YOU AND YOUR ENTOURAGE

2. The Material/Map Browser opens, displaying materials. Select Standard from the list and click
OK to close the dialog box. All the parameters change in the Material Editor to correspond to
the Standard material.
3. In the Blinn Basic Parameters rollout, click the blank button next to the Diffuse color swatch.

4. The Material/Map Browser opens again, but this time it displays maps. Choose Bitmap from
the extensive list and click OK. The Select Bitmap Image File dialog box opens automatically
in this standard file browser. Select WomanStanding.tif and click Open. The Material Editor’s
rollouts change to those of the bitmap. Click the Go To Parent button to return to the top of the
material hierarchy.

Now that you have the diffuse color map, the next task is to copy it to create an opacity map.
The opacity map determines the boundaries of the object and gets its data from the image’s
alpha channel.
5. Drag the M icon (meaning mapped) from the Diffuse Color channel to the Opacity channel, as
shown in Figure 4.41. The Copy (Instance) Map dialog box opens. Click the Copy radio button
and then click OK. Because the Opacity map must take data from the image’s alpha channel,
it is necessarily different from the diffuse map, so a unique copy is needed.
Figure 4.41
Copy the diffuse map to
the opacity Map.

Drag the map from here… …to here.

Right now you have an identical copy of the diffuse map in the Opacity channel. You still must
change the output of the opacity map to read the alpha channel of the image; otherwise, it
reads the RGB values by default to determine opacity.
6. Click the M button next to the Opacity channel to enter a deeper level of the material hierarchy.
The Bitmap controls appear in the Material Editor. Scroll down and locate the Bitmap Param-
eters rollout. Click the Alpha radio button in the Mono Channel Output group. Click the Go To
Parent button to return to the top level of the material hierarchy.