vgatest(6) Svgalib User Manual vgatest(6)NAMEvgatest - makes basic tests on any svgalib graphics mode
SYNOPSISvgatestDESCRIPTION
Mode test program. First the program gives a list of the supported
modes, then you enter a number and vgatest displays a test pattern in
that mode.
The test pattern consists of a sequence of crosses (in different col‐
ors, if the mode support has different colors) in the top left corner.
Below you see either four horizontal color bars (white, red, green, and
blue with increasing intensity from left to right) or vertical stripes.
If the mode has 32K or more colors, six squares will appear on top of
that, each showing some different smooth color shades
The whole pattern is enclosed in a white border around the edge of the
screen.
See below for details of the test pattern in case you need to verify
that it is being displayed correctly or diagnose a problem with the
display.
It also shows some details from vga_getmodeinfo(3).
To terminate the display and exit the program, hit any key. If that
key is 'd', vgatest dumps the values of all the SVGA registers to Stan‐
dard Output, in the manner of vga_dumpregs() before exiting.
This demo is part of svgalib and can be found in the demos/ subdirec‐
tory of the original svgalib distribution. However, it is not installed
in the system by default, s.t. it is unclear where you can find it if
your svgalib was installed by some linux distribution. Even then, when
you have the demo on your system, you probably won't have the sources
s.t. it is only of limited use for you.
In case of any such problem, simply get an svgalib distribution from
the net. You even don't need to install it. Just make in the demos/
subdirecty. As of this writing, svgalib-1.2.12.tar.gz is the latest
version and can be retrieved by ftp from sunsite.unc.edu at
/pub/Linux/libs/graphics and tsx-11.mit.edu at /pub/linux/sources/libs
which will most probably be mirrored by a site close to you.
The Test Pattern
Here are the details of the test pattern that vgatest displays.
The screen is surrounded by a white frame which is at the very edges of
the screen and one pixel thick.
At the top of the screen is a set of 16 overlapping crosses, lined up
horizontally 5 pixels apart. Each cross is composed of a one pixel
thick line sloping down at 45 degrees and one sloping up at 45 degrees
meeting in the center. The top of each of these lines is at the 11th
raster line on the screen and the bottom is at the 90th, so the crosses
are 80 lines high. The leftmost pixel of the crosses is in the 11th
column of the screen and the rightmost is in the 165th column. The
lines are in multiple colors, but each line is one color (except where
it intersects another line).
Below the crosses are either 4 horizontal bands of color or vertical
bars. If the mode has 2 or 16 colors, you get the vertical bars. If
the mode has 256, 32K, 64K, or 16M colors, you get the horizontal bands
of color.
For a 2 color mode, the vertical bars are are one pixel wide white
bars, spaced 4 pixels apart all the way across the screen on a black
background. The first white bar is in the 3rd column. (But don't for‐
get the white border described above).
For a 16 color mode, the vertical bars are one pixel wide and contigu‐
ous, filling the 3rd column from the left through the 3rd column from
the right. The bars cycle through each of the 16 colors from left to
right.
The vertical bars start in the 101st raster line and end in the 3rd
line from the bottom of the screen.
For a higher color mode, the color bands fill the 3rd column from the
left through the 3rd column from the right. (leaving a column of black
and the aforementioned white border at the edges). The bands are all
the same height with nothing between them. They are as large as will
fit starting in the 101st line of the screen and ending at or before
the 3rd line from the bottom. So depending on the number of lines on
the screen, there are 1, 2, 3, or 4 black lines between the lowest bar
and the white bottom border.
The hues of the bands are, from top to bottom, white, red, green, and
blue. Each band goes from zero to maximal brightness from left to
right.
In addition to the color bands, for a mode with 32K or more colors, six
squares, 64 pixels on a side are arranged in a matrix centered on the
screen, spaced 32 pixels apart. They replace any other part of the
test pattern. These are actual squares only if your monitor displays
square pixels in this mode, i.e. 64 columns is the same length as 64
lines. Normal monitors, properly adjusted, display square pixels for
1024 x 768 modes, but may not for other geometries.
Each square contains 4096 different colors, one pixel per color, in
smooth transition. In each top square, one color component (red,
green, or blue) is zero another varies linearly in the vertical direc‐
tion and the other varies linearly in the Y direction. The bottom
squares are the same except that one color component is maximum instead
of zero.
SEE ALSOsvgalib(7), vgagl(7), libvga.config(5), vga_getmodeinfo(3), threed(6),
accel(6), bg_test(6), eventtest(6), forktest(6), fun(6), keytest(6),
mousetest(6), scrolltest(6), speedtest(6), spin(6), testaccel(6),
testgl(6), testlinear(6), plane(6), wrapdemo(6)AUTHOR
This manual page was edited by Michael Weller <eowmob@exp-math.uni-
essen.de>. The exact source of the referenced demo as well as of the
original documentation is unknown.
It is very likely that both are at least to some extent are due to Harm
Hanemaayer <H.Hanemaayer@inter.nl.net>.
Occasionally this might be wrong. I hereby asked to be excused by the
original author and will happily accept any additions or corrections to
this first version of the svgalib manual.
Svgalib (>= 1.9.13) 01 January 2001 vgatest(6)