void bar(int x,int y,register int wl,register int ll,int color)
/*用color色填充矩形區(qū)域，以(x,y)為起點(diǎn)填充一長(zhǎng)寬為(wl,ll)的矩形區(qū)域*/
{register int j,n[4]={256,512,128,384};
 int temp;register char page_new,page_old,page_end;
 register long position;
 register char *p=MK_FP(0xa000,0000),buffer[640];
 page_old=8;
 selectpage(page_old);
 for(j=0;j<wl;j++)buffer[j]=color;
 for(j=y;j<=ll+y;j++)
  {position=640l*j+x;
   page_new=position/65536;
   page_end=(position+wl)/65536;
   if(page_new!=page_old)
    {selectpage(page_new);page_old=page_new;}	/*處理跳行跨頁(yè)*/
   if(page_new!=page_end)	/*處理顯示行跨頁(yè)*/
   {memcpy(p+position%65536,buffer,n[page_new]-x);
    selectpage(page_new+1);
    memcpy(p,buffer,x+wl-n[page_new]);
    selectpage(page_new);
   }
   else memcpy(p+position%65536,buffer,wl);
  }
}