vga_setlogicalwidth man page
vga_setlogicalwidth — set the logical scanline width
void vga_setlogicalwidth(int l);
Set the logical scanline width to l bytes. It must be a multiple of 8. Only changes the VGA register, drawing functions don't take it into account. The logical scan line width is the offset between points above each other in consecutive lines. Note that for some cards and graphics modes a multiple of 8 will not suffice to ensure a proper video timing. You should only set l to multiples of the value returned for that graphics mode by vga_modeinfo(3).
svgalib(7), vgagl(7), libvga.config(5), vga_modeinfo(3), vga_displaystart(3), vga_claimvideomemory(3)
This manual page was edited by Michael Weller <email@example.com>. The exact source of the referenced function 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(7), vga_copytoplanar16(3), vga_copytoplanar256(3), vga_copytoplane(3), vga_getmodeinfo(3), vga_setdisplaystart(3).