File:  [DragonFly] / src / games / trek / move.c
Revision 1.3: download - view: text, annotated - select for diffs
Thu Sep 7 21:19:44 2006 UTC (7 years, 11 months ago) by pavalos
Branches: MAIN
CVS tags: HEAD, DragonFly_RELEASE_2_0_Slip, DragonFly_RELEASE_2_0, DragonFly_RELEASE_1_8_Slip, DragonFly_RELEASE_1_8, DragonFly_RELEASE_1_12_Slip, DragonFly_RELEASE_1_12, DragonFly_RELEASE_1_10_Slip, DragonFly_RELEASE_1_10, DragonFly_Preview
WARNS6 cleanup (1803 warnings).

ANSI function declarations.

Staticize functions.

Rename local variables that shadow globals.

Use string functions from libc instead of creating our own.

Remove void casts for unchecked function returns.

Spell parameter correctly.

Don't try to return a value from void functions.

Remove compat library requirement (gtty -> ioctl).

Add new function "dowarp" that calls warp() from play.c.  (Taken from
NetBSD).

Change chars that are used for numeric values to shorts so they can be
properly used as array indexes.

/*
 * Copyright (c) 1980, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * @(#)move.c	8.1 (Berkeley) 5/31/93
 * $FreeBSD: src/games/trek/move.c,v 1.6 1999/11/30 03:49:50 billf Exp $
 * $DragonFly: src/games/trek/move.c,v 1.3 2006/09/07 21:19:44 pavalos Exp $
 */

# include	"trek.h"

/*
**  Move Under Warp or Impulse Power
**
**	`Ramflag' is set if we are to be allowed to ram stars,
**	Klingons, etc.  This is passed from warp(), which gets it from
**	either play() or ram().  Course is the course (0 -> 360) at
**	which we want to move.  `Speed' is the speed we
**	want to go, and `p_time' is the expected time.  It
**	can get cut short if a long range tractor beam is to occur.  We
**	cut short the move so that the user doesn't get docked time and
**	energy for distance which he didn't travel.
**
**	We check the course through the current quadrant to see that he
**	doesn't run into anything.  After that, though, space sort of
**	bends around him.  Note that this puts us in the awkward posi-
**	tion of being able to be dropped into a sector which is com-
**	pletely surrounded by stars.  Oh Well.
**
**	If the SINS (Space Inertial Navigation System) is out, we ran-
**	domize the course accordingly before ever starting to move.
**	We will still move in a straight line.
**
**	Note that if your computer is out, you ram things anyway.  In
**	other words, if your computer and sins are both out, you're in
**	potentially very bad shape.
**
**	Klingons get a chance to zap you as you leave the quadrant.
**	By the way, they also try to follow you (heh heh).
**
**	Return value is the actual amount of time used.
**
**
**	Uses trace flag 4.
*/

double
move(int ramflag, int course, double p_time, double speed)
{
	double			angle;
	double			x, y, dx, dy;
	int		ix, iy;
	double			bigger;
	int			n;
	int		i;
	double			dist;
	double			sectsize;
	double			xn;
	double			evtime;

	ix = iy = 0;
#	ifdef xTRACE
	if (Trace)
		printf("move: ramflag %d course %d time %.2f speed %.2f\n",
			ramflag, course, p_time, speed);
#	endif
	sectsize = NSECTS;
	/* initialize delta factors for move */
	angle = course * 0.0174532925;
	if (damaged(SINS))
		angle += Param.navigcrud[1] * (franf() - 0.5);
	else
		if (Ship.sinsbad)
			angle += Param.navigcrud[0] * (franf() - 0.5);
	dx = -cos(angle);
	dy = sin(angle);
	bigger = fabs(dx);
	dist = fabs(dy);
	if (dist > bigger)
		bigger = dist;
	dx /= bigger;
	dy /= bigger;

	/* check for long range tractor beams */
	/****  TEMPORARY CODE == DEBUGGING  ****/
	evtime = Now.eventptr[E_LRTB]->date - Now.date;
#	ifdef xTRACE
	if (Trace)
		printf("E.ep = %p, ->evcode = %d, ->date = %.2f, evtime = %.2f\n",
			(void *)Now.eventptr[E_LRTB],
			Now.eventptr[E_LRTB]->evcode,
			Now.eventptr[E_LRTB]->date, evtime);
#	endif
	if (p_time > evtime && Etc.nkling < 3)
	{
		/* then we got a LRTB */
		evtime += 0.005;
		p_time = evtime;
	}
	else
		evtime = -1.0e50;
	dist = p_time * speed;

	/* move within quadrant */
	Sect[Ship.sectx][Ship.secty] = EMPTY;
	x = Ship.sectx + 0.5;
	y = Ship.secty + 0.5;
	xn = NSECTS * dist * bigger;
	n = xn + 0.5;
#	ifdef xTRACE
	if (Trace)
		printf("dx = %.2f, dy = %.2f, xn = %.2f, n = %d\n", dx, dy, xn, n);
#	endif
	Move.free = 0;

	for (i = 0; i < n; i++)
	{
		ix = (x += dx);
		iy = (y += dy);
#		ifdef xTRACE
		if (Trace)
			printf("ix = %d, x = %.2f, iy = %d, y = %.2f\n", ix, x, iy, y);
#		endif
		if (x < 0.0 || y < 0.0 || x >= sectsize || y >= sectsize)
		{
			/* enter new quadrant */
			dx = Ship.quadx * NSECTS + Ship.sectx + dx * xn;
			dy = Ship.quady * NSECTS + Ship.secty + dy * xn;
			if (dx < 0.0)
				ix = -1;
			else
				ix = dx + 0.5;
			if (dy < 0.0)
				iy = -1;
			else
				iy = dy + 0.5;
#			ifdef xTRACE
			if (Trace)
				printf("New quad: ix = %d, iy = %d\n", ix, iy);
#			endif
			Ship.sectx = x;
			Ship.secty = y;
			compkldist(0);
			Move.newquad = 2;
			attack(0);
			checkcond();
			Ship.quadx = ix / NSECTS;
			Ship.quady = iy / NSECTS;
			Ship.sectx = ix % NSECTS;
			Ship.secty = iy % NSECTS;
			if (ix < 0 || Ship.quadx >= NQUADS || iy < 0 || Ship.quady >= NQUADS)
			{
				if (!damaged(COMPUTER))
				{
					dumpme(0);
				}
				else
					lose(L_NEGENB);
			}
			initquad(0);
			n = 0;
			break;
		}
		if (Sect[ix][iy] != EMPTY)
		{
			/* we just hit something */
			if (!damaged(COMPUTER) && ramflag <= 0)
			{
				ix = x - dx;
				iy = y - dy;
				printf("Computer reports navigation error; %s stopped at %d,%d\n",
					Ship.shipname, ix, iy);
				Ship.energy -= Param.stopengy * speed;
				break;
			}
			/* test for a black hole */
			if (Sect[ix][iy] == HOLE)
			{
				/* get dumped elsewhere in the galaxy */
				dumpme(1);
				initquad(0);
				n = 0;
				break;
			}
			ram(ix, iy);
			break;
		}
	}
	if (n > 0)
	{
		dx = Ship.sectx - ix;
		dy = Ship.secty - iy;
		dist = sqrt(dx * dx + dy * dy) / NSECTS;
		p_time = dist / speed;
		if (evtime > p_time)
			p_time = evtime;		/* spring the LRTB trap */
		Ship.sectx = ix;
		Ship.secty = iy;
	}
	Sect[Ship.sectx][Ship.secty] = Ship.ship;
	compkldist(0);
	return (p_time);
}