Rendering and Materials - AutoCAD 2011 and AutoCAD LT 2011: No Experience Required - page 937

NOTE During the rendering process, you probably noticed the small
black squares being replaced one at a time by small areas of the rendered
drawing. this indicates that autoCaD is using bucket rendering. Before the
rendering process begins, autoCaD determines the sequence to process
the squares, called buckets , in order to maximize the memory usage and
thereby increase the efficiency of the rendering.
Adjusting the Material Mapping
Image maps are the components of a material that consist of image files, such
as a JPEG or TIFF. When a material uses an image map, its purpose can be to
change the color of an object (diffuse maps), to give the illusion of texture (bump
maps), or to define the transparency of a surface (opacity maps).
Adjusting the Map Size
The individual properties of all materials are controlled in the Materials Browser
palette. Here you'll find the controls for setting the parameters for the size of
the map, which map to use, and several other features for the selected material.
1. In the Render tab, click the Materials Browser icon in the Materials
panel.
2. In the Document Materials portion of the Materials Browser palette,
right-click on the Shakes Weathered material and select Edit.
The Materials Editor palette opens to display details about the Shakes
Weathered material (see Figure 17.28).
3. From the Materials Editor, click on the photographic image found
under the Generic group (see Figure 17.28).
4. Selecting the image in the Materials Editor palette will open the
Texture Editor palette, shown in Figure 17.29. Expand the Transforms
group, and then the Scale group to locate the Sample Size setting.
Enter 2 ′ 4 ″ (710 mm) into the Height textbox. Note how the dimen-
sions shown in the preview at the top of the Texture Editor palette
update to reflect this change.
5. Close the Texture Editor, Materials Editor, and Materials Browser pal-
ettes, and then change your visual style to Realistic.
The Realistic style displays the materials and maps, and the changes
that you make to them, all at the expense of system performance (see
Figure 17.30). You should use this visual style only when necessary.