# From the module docs
use Linux::Svgalib;

my $svga = Linux::Svgalib->new();
$svga->init();
$svga->setmode(G640x480x16);

# Set the color for the subsequent ops
$svga->setcolor($color);
# Place a pixel
$svga->drawpixel($x, $y);
# Draw a line
$svga->drawline($x1, $y1, $x2, $y2);

# ...and so on; see the other methods in the documentation

$svga->setmode(TEXT);