usr/src/old/lib2648/motion.c

/*      motion.c        4.1     83/03/09        */
/*
 * Move the pen to x, y.  We assume we are already in ESCP mode.
 */

#include "2648.h"

motion(x, y)
{
        char lox, loy, hix, hiy;
        int delx, dely;

        delx = x-_penx; dely = y-_peny;
        if (-16 <= delx && delx <= 15 && -16 <= dely && dely <= 15) {
                /*
                 * Optimization: if within 15 in both directions, can use
                 * HP short incremental mode, only 3 bytes.
                 */
                outchar('j');
                outchar(32 + (delx & 31));
                outchar(32 + (dely & 31));
        } else {
                /*
                 * Otherwise must use binary absolute mode, 5 bytes.
                 * We never use ascii mode or binary incremental, since
                 * those both take many more bytes.
                 */
                outchar('i');
                outchar(32+ ((x>>5) & 31));
                outchar(32+ (x&31));
                outchar(32+ ((y>>5) & 31));
                outchar(32+ (y&31));
        }
        _penx = x;
        _peny = y;
}