ref: f870bc6589f353a45af7c24df73fa43346161aec
dir: /span.c/
#include "quakedef.h"
void
dospan(byte *pdest, byte *pbase, int s, int t, int sstep, int tstep, int spancount, int cachewidth)
{
do{
*pdest++ = pbase[(s >> 16) + (t >> 16) * cachewidth];
s += sstep;
t += tstep;
}while(--spancount);
}