ref: b92b18d15ebabc0879641d758b3c3e2c081bdf71
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);
}