mvcur.c

<B>Digital的Unix操作系统VAX 4.2源码</B>

		/* some tabs plus some lefts */
		nleft = tabcol - newcol;
		c1 = ntabs*_cost(Tab) + nleft*_cost(Cursor_left);
	}

	c0 = (newcol - oldcol) * _cost(Cursor_right);

	if (parm_right_cursor)
		c2 = _cost(Parm_right_cursor);
	else
		c2 = INFINITY;

	if (column_address)
		c3 = _cost(Column_address);
	else
		c3 = INFINITY;
	
#ifdef DEBUG
	if(outf) fprintf(outf, "_loc_right(%d, %d, %d), chars %d, ri %d, RI %d, ch %d\n",
		oldcol, newcol, domotion, c0, c1, c2, c3);
#endif

	/* Decide and maybe do them */
	if (c3 <= c1 && c3 <= c2 && c3 <= c0) {
		/* cheapest to use column absolute cursor addressing */
#ifdef DEBUG
		if(outf) fprintf(outf, "chose column absolute cursor addressing\n");
#endif
		if (domotion)
			tputs(tparm(column_address, newcol), 1, _outch);
		return c3;
	} else if (c2 <= c1 && c2 <= c0) {
		/* cheapest to use column relative motion */
#ifdef DEBUG
		if(outf) fprintf(outf, "chose column relative motion\n");
#endif
		if (domotion)
			tputs(tparm(parm_right_cursor, newcol-oldcol), 1, _outch);
		return c2;
	} else {
		/* cheapest to use several right commands */
#ifdef DEBUG
		if(outf) fprintf(outf, "chose rights: ntabs %d, tabcol %d, nleft %d, nright %d\n", ntabs, tabcol, nleft, nright);
#endif
		if (domotion)
			if (c1 < c0) {
				for (i=0; i<ntabs; i++)
					tputs(tab, 1, _outch);
				if (tabcol < newcol) {
					/* some tabs plus some rights */
					for (i=0; i<nright; i++) {
#ifdef DEBUG
	if (outf && SP->cur_body[row+1]) fprintf(outf, "nd1, row %d col %d+%d=%d, char '%c'\n",
	row, tabcol, i, tabcol+i, SP->cur_body[row+1]->body[tabcol+i]);
#endif
						rp = SP->cur_body[row+1];
						if (cursor_right && (!notinsmode || rp && SP->phys_gr != (rp->body[tabcol+i] & A_ATTRIBUTES))) /* dont know */
							tputs(cursor_right,1,_outch);
						else if (rp && rp->length > tabcol+i)
							/* Note we assume dumb terminals without cursor_right don't have
							 * standout either, otherwise we should go into right standout
							 * mode here and in the essentially similar code below.
							 */
							_outch(rp->body[tabcol+i]&A_CHARTEXT);
						else	/* off edge */
							_outch(' ');
					}
				} else {
					/* some tabs plus some lefts */
					for (i=0; i<nleft; i++)
						tputs(cursor_left,1,_outch);
				}
			} else {
				for (i=oldcol; i<newcol; i++) {
#ifdef DEBUG
	if (outf && SP->cur_body[row+1]) fprintf(outf, "nd2, row %d col %d, char '%c'\n",
	row, i, SP->cur_body[row+1]->body[i]);
#endif
					rp = SP->cur_body[row+1];
					if (cursor_right && (!notinsmode || rp && SP->phys_gr != (rp->body[i] & A_ATTRIBUTES))) /* dont know */
						tputs(cursor_right,1,_outch);
					else if (rp && rp->length > i)
						_outch(rp->body[i]&A_CHARTEXT);
					else	/* off edge */
						_outch(' ');
				}
			}
		return (c1 < c0) ? c1 : c0;
	}
}

static
_loc_left(oldcol, newcol, domotion)
{
	int c1, c2, c3;
	int i, tabcol, ntabs, nright, nleft;

	if (newcol > oldcol)	/* can't go right with left motions */
		return INFINITY;
	if (newcol == oldcol)
		return 0;	/* already there - nothing to do */

	/* figure out various costs */
	if (cursor_left) {
		if (back_tab) {
			tabcol = (newcol+4)/8 * 8;   /* round to nearest 8 */
			/* tab past left margin is undefined */
			if (tabcol < 8)
				tabcol = 8;
			ntabs = (oldcol-tabcol+7)/8;
			if (ntabs <= 0)
				tabcol = oldcol;
			if (tabcol < newcol) {
				/* some backtabs plus some rights */
				nright = newcol - tabcol;
				c1 = ntabs*_cost(Back_tab) + nright*_cost(Cursor_right);
			} else {
				/* some tabs plus some lefts */
				nleft = tabcol - newcol;
				c1 = ntabs*_cost(Back_tab) + nleft*_cost(Cursor_left);
			}
		} else {
			c1 = (oldcol - newcol) * _cost(Cursor_left);
		}
	} else
		c1 = INFINITY;
	if (parm_left_cursor)
		c2 = _cost(Parm_left_cursor);
	else
		c2 = INFINITY;
	if (column_address)
		c3 = _cost(Column_address);
	else
		c3 = INFINITY;
	
#ifdef DEBUG
	if(outf) fprintf(outf, "_loc_left(%d, %d, %d), le %d, LE %d, ch %d\n",
		oldcol, newcol, domotion, c1, c2, c3);
#endif

	/* Decide and maybe do them */
	if (c3 <= c1 && c3 <= c2) {
		/* cheapest to use column absolute cursor addressing */
#ifdef DEBUG
		if(outf) fprintf(outf, "chose column absolute cursor addressing\n");
#endif
		if (domotion)
			tputs(tparm(column_address, newcol), 1, _outch);
		return c3;
	} else if (c2 <= c1) {
		/* cheapest to use column relative motion */
#ifdef DEBUG
		if(outf) fprintf(outf, "chose column relative motion\n");
#endif
		if (domotion)
			tputs(tparm(parm_left_cursor, oldcol-newcol), 1, _outch);
		return c2;
	} else {
		/* cheapest to use several left commands */
#ifdef DEBUG
		if(outf) fprintf(outf, "chose several left commands\n");
#endif
		if (domotion)
			if (back_tab) {
				for (i=0; i<ntabs; i++)
					tputs(back_tab, 1, _outch);
				if (tabcol < newcol) {
					/* some tabs plus some rights */
					for (i=0; i<nright; i++)
						tputs(cursor_right,1, _outch);
				} else {
					/* some tabs plus some lefts */
					for (i=0; i<nleft; i++)
						tputs(cursor_left,1,_outch);
				}
			} else {
				for (i=oldcol; i>newcol; i--)
					tputs(cursor_left, 1, _outch);
			}
		return c1;
	}
}

static
_loc_up(oldrow, newrow, domotion)
{
	int c1, c2, c3, i;

	if (newrow > oldrow)	/* can't go down with up motions */
		return INFINITY;
	if (newrow == oldrow)
		return 0;	/* already there - nothing to do */

	/* figure out various costs */
	if (cursor_up)
		c1 = (oldrow - newrow) * _cost(Cursor_up);
	else
		c1 = INFINITY;
	if (parm_up_cursor)
		c2 = _cost(Parm_up_cursor);
	else
		c2 = INFINITY;
	if (row_address)
		c3 = _cost(Row_address);
	else
		c3 = INFINITY;
	
#ifdef DEBUG
	if(outf) fprintf(outf, "_loc_up(%d, %d, %d), up %d, UP %d, cv %d\n",
		oldrow, newrow, domotion, c1, c2, c3);
#endif

	/* Decide and maybe do them */
	if (c3 <= c1 && c3 <= c2) {
		/* cheapest to use row absolute cursor addressing */
#ifdef DEBUG
		if(outf) fprintf(outf, "chose row absolute cursor addressing\n");
#endif
		if (domotion)
			tputs(tparm(row_address, newrow), 1, _outch);
		return c3;
	} else if (c2 <= c1) {
		/* cheapest to use row relative motion */
#ifdef DEBUG
		if(outf) fprintf(outf, "chose row relative motion\n");
#endif
		if (domotion)
			tputs(tparm(parm_up_cursor, oldrow-newrow), 1, _outch);
		return c2;
	} else {
		/* cheapest to use several up commands */
#ifdef DEBUG
		if(outf) fprintf(outf, "chose several up commands\n");
#endif
		if (domotion)
			for (i=oldrow; i>newrow; i--)
				tputs(cursor_up, 1, _outch);
		return c1;
	}
}

static
_loc_down(oldrow, newrow, domotion, col)
{
	int c1, c2, c3, i;

	if (newrow < oldrow)	/* can't go up with down motions */
		return INFINITY;
	if (newrow == oldrow)
		return 0;	/* already there - nothing to do */

	/* figure out various costs */
	if (cursor_down && (col==0 || bare_lf_ok || *cursor_down!='\n'))
		c1 = (newrow - oldrow) * _cost(Cursor_down);
	else
		c1 = INFINITY;
	if (parm_down_cursor)
		c2 = _cost(Parm_down_cursor);
	else
		c2 = INFINITY;
	if (row_address)
		c3 = _cost(Row_address);
	else
		c3 = INFINITY;
	
#ifdef DEBUG
	if(outf) fprintf(outf, "_loc_down(%d, %d, %d, %d), do %d, DO %d, cv %d\n",
		oldrow, newrow, domotion, col,c1, c2, c3);
#endif

	/* Decide and maybe do them */
	if (c3 <= c1 && c3 <= c2) {
		/* cheapest to use row absolute cursor addressing */
#ifdef DEBUG
		if(outf) fprintf(outf, "chose row absolute cursor addressing\n");
#endif
		if (domotion)
			tputs(tparm(row_address, newrow), 1, _outch);
		return c3;
	} else if (c2 <= c1) {
		/* cheapest to use row relative motion */
#ifdef DEBUG
		if(outf) fprintf(outf, "chose row relative motion\n");
#endif
		if (domotion)
			tputs(tparm(parm_down_cursor, newrow-oldrow), 1, _outch);
		return c2;
	} else {
		/* cheapest to use several down commands */
#ifdef DEBUG
		if(outf) fprintf(outf, "chose several down commands\n");
#endif
		if (domotion)
			for (i=oldrow; i<newrow; i++)
				tputs(cursor_down, 1, _outch);
		return c1;
	}
}