Using Displays
Color Mapping
11-6
SPARCbook Portable Workstation User Guide
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Zoom to view
With zoom to view, one pixel in the emulated frame buffer
image is expanded to four pixels on the display resulting in an
image that is four times the size of the original. This displays a
smaller part of the stored image but in greater detail, although
objects may look ragged. This view is most useful when used
with large format public displays when you want an audience to
focus on a particular area of detail. You can view hidden parts of
the image by panning.
Color Mapping
Each pixel on the display can be represented in video memory by 8 bits,
16 bits or 32 bits. The number of bits in each pixel determines the range
of colors that it can display. When 8 bits per pixel are used, the pixel
data is used to select an entry in a 24-bit color palette to obtain an 8-bit
intensity value for each of the red, green and blue color channels. Thus,
you get 256 colors displayed simultaneously from a palette of
16,777,216.
When 16- and 32-bits per pixel are used, the pixel data controls directly
the intensity of the red, green and blue video channels. These modes are
refered to as true color modes for this reason. With 16 bits per pixel, 5
bits are used to control the intensity of red, 6 bits for green and 5 bits for
blue. The 32-bit depth uses 8 bits for each of the red, green and blue
channels; the upper 8 bits of the 32-bit word are unused.
Setting the color mode
The color mode can be set by using the Display Editor in the NCE
Display Panel. See “Configuring the Display Interface Using NCE” on
page 11-9. You can also use the
fbconfig
command at the Solaris
command prompt. See “Configuring the Display Interface at the
Command Prompt” on page 11-11.
S3UG4_Book Page 6 Friday, August 8, 1997 11:37 am
