File:  [DragonFly] / src / games / trek / phaser.c
Revision 1.3: download - view: text, annotated - select for diffs
Thu Sep 7 21:19:44 2006 UTC (7 years, 7 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.
 *
 * @(#)phaser.c	8.1 (Berkeley) 5/31/93
 * $FreeBSD: src/games/trek/phaser.c,v 1.5.2.1 2000/07/20 10:35:07 kris Exp $
 * $DragonFly: src/games/trek/phaser.c,v 1.3 2006/09/07 21:19:44 pavalos Exp $
 */

# include	"trek.h"
# include	"getpar.h"

/* factors for phaser hits; see description below */

# define	ALPHA		3.0		/* spread */
# define	BETA		3.0		/* franf() */
# define	GAMMA		0.30		/* cos(angle) */
# define	EPSILON		150.0		/* dist ** 2 */
# define	OMEGA		10.596		/* overall scaling factor */

/* OMEGA ~= 100 * (ALPHA + 1) * (BETA + 1) / (EPSILON + 1) */

/*
**  Phaser Control
**
**	There are up to NBANKS phaser banks which may be fired
**	simultaneously.  There are two modes, "manual" and
**	"automatic".  In manual mode, you specify exactly which
**	direction you want each bank to be aimed, the number
**	of units to fire, and the spread angle.  In automatic
**	mode, you give only the total number of units to fire.
**
**	The spread is specified as a number between zero and
**	one, with zero being minimum spread and one being maximum
**	spread.  You  will normally want zero spread, unless your
**	short range scanners are out, in which case you probably
**	don't know exactly where the Klingons are.  In that case,
**	you really don't have any choice except to specify a
**	fairly large spread.
**
**	Phasers spread slightly, even if you specify zero spread.
**
**	Uses trace flag 30
*/

struct cvntab	Matab[] =
{
	{ "m",		"anual",	(void (*)(int))1,	0 },
	{ "a",		"utomatic",	(void (*)(int))0,	0 },
	{ NULL,		NULL,		NULL,			0 }
};

struct banks
{
	int	units;
	double	angle;
	double	spread;
};


void
phaser(__unused int unused)
{
	int		i;
	int			j;
	struct kling	*k;
	double			dx, dy;
	double			anglefactor, distfactor;
	struct banks	*b;
	int			manual, flag, extra = 0;
	int			hit;
	double			tot;
	int			n;
	int			hitreqd[NBANKS];
	struct banks		bank[NBANKS];
	struct cvntab		*ptr;

	if (Ship.cond == DOCKED) {
		printf("Phasers cannot fire through starbase shields\n");
		return;
	}
	if (damaged(PHASER)) {
		out(PHASER);
		return;
	}
	if (Ship.shldup) {
		printf("Sulu: Captain, we cannot fire through shields.\n");
		return;
	}
	if (Ship.cloaked)
	{
		printf("Sulu: Captain, surely you must realize that we cannot fire\n");
		printf("  phasers with the cloaking device up.\n");
		return;
	}

	/* decide if we want manual or automatic mode */
	manual = 0;
	if (testnl())
	{
		if (damaged(COMPUTER))
		{
			printf("%s", Device[COMPUTER].name);
			manual++;
		}
		else
			if (damaged(SRSCAN))
			{
				printf("%s", Device[SRSCAN].name);
				manual++;
			}
		if (manual)
			printf(" damaged, manual mode selected\n");
	}

	if (!manual)
	{
		ptr = getcodpar("Manual or automatic", Matab);
		manual = (long) ptr->value;
	}
	if (!manual && damaged(COMPUTER))
	{
		printf("Computer damaged, manual selected\n");
		skiptonl(0);
		manual++;
	}

	/* initialize the bank[] array */
	flag = 1;
	for (i = 0; i < NBANKS; i++)
		bank[i].units = 0;
	if (manual)
	{
		/* collect manual mode statistics */
		while (flag)
		{
			printf("%d units available\n", Ship.energy);
			extra = 0;
			flag = 0;
			for (i = 0; i < NBANKS; i++)
			{
				b = &bank[i];
				printf("\nBank %d:\n", i);
				hit = getintpar("units");
				if (hit < 0)
					return;
				if (hit == 0)
					break;
				extra += hit;
				if (extra > Ship.energy)
				{
					printf("available energy exceeded.  ");
					skiptonl(0);
					flag++;
					break;
				}
				b->units = hit;
				hit = getintpar("course");
				if (hit < 0 || hit > 360)
					return;
				b->angle = hit * 0.0174532925;
				b->spread = getfltpar("spread");
				if (b->spread < 0 || b->spread > 1)
					return;
			}
			Ship.energy -= extra;
		}
		extra = 0;
	}
	else
	{
		/* automatic distribution of power */
		if (Etc.nkling <= 0) {
			printf("Sulu: But there are no Klingons in this quadrant\n");
			return;
		}
		printf("Phasers locked on target.  ");
		while (flag)
		{
			printf("%d units available\n", Ship.energy);
			hit = getintpar("Units to fire");
			if (hit <= 0)
				return;
			if (hit > Ship.energy)
			{
				printf("available energy exceeded.  ");
				skiptonl(0);
				continue;
			}
			flag = 0;
			Ship.energy -= hit;
			extra = hit;
			n = Etc.nkling;
			if (n > NBANKS)
				n = NBANKS;
			tot = n * (n + 1) / 2;
			for (i = 0; i < n; i++)
			{
				k = &Etc.klingon[i];
				b = &bank[i];
				distfactor = k->dist;
				anglefactor = ALPHA * BETA * OMEGA / (distfactor * distfactor + EPSILON);
				anglefactor *= GAMMA;
				distfactor = k->power;
				distfactor /= anglefactor;
				hitreqd[i] = distfactor + 0.5;
				dx = Ship.sectx - k->x;
				dy = k->y - Ship.secty;
				b->angle = atan2(dy, dx);
				b->spread = 0.0;
				b->units = ((n - i) / tot) * extra;
#				ifdef xTRACE
				if (Trace)
				{
					printf("b%d hr%d u%d df%.2f af%.2f\n",
						i, hitreqd[i], b->units,
						distfactor, anglefactor);
				}
#				endif
				extra -= b->units;
				hit = b->units - hitreqd[i];
				if (hit > 0)
				{
					extra += hit;
					b->units -= hit;
				}
			}

			/* give out any extra energy we might have around */
			if (extra > 0)
			{
				for (i = 0; i < n; i++)
				{
					b = &bank[i];
					hit = hitreqd[i] - b->units;
					if (hit <= 0)
						continue;
					if (hit >= extra)
					{
						b->units += extra;
						extra = 0;
						break;
					}
					b->units = hitreqd[i];
					extra -= hit;
				}
				if (extra > 0)
					printf("%d units overkill\n", extra);
			}
		}
	}

#	ifdef xTRACE
	if (Trace)
	{
		for (i = 0; i < NBANKS; i++)
		{
			b = &bank[i];
			printf("b%d u%d", i, b->units);
			if (b->units > 0)
				printf(" a%.2f s%.2f\n", b->angle, b->spread);
			else
				printf("\n");
		}
	}
#	endif

	/* actually fire the shots */
	Move.free = 0;
	for (i = 0; i < NBANKS; i++)
	{
		b = &bank[i];
		if (b->units <= 0)
		{
			continue;
		}
		printf("\nPhaser bank %d fires:\n", i);
		n = Etc.nkling;
		k = Etc.klingon;
		for (j = 0; j < n; j++)
		{
			if (b->units <= 0)
				break;
			/*
			** The formula for hit is as follows:
			**
			**  zap = OMEGA * [(sigma + ALPHA) * (rho + BETA)]
			**	/ (dist ** 2 + EPSILON)]
			**	* [cos(delta * sigma) + GAMMA]
			**	* hit
			**
			** where sigma is the spread factor,
			** rho is a random number (0 -> 1),
			** GAMMA is a crud factor for angle (essentially
			**	cruds up the spread factor),
			** delta is the difference in radians between the
			**	angle you are shooting at and the actual
			**	angle of the klingon,
			** ALPHA scales down the significance of sigma,
			** BETA scales down the significance of rho,
			** OMEGA is the magic number which makes everything
			**	up to "* hit" between zero and one,
			** dist is the distance to the klingon
			** hit is the number of units in the bank, and
			** zap is the amount of the actual hit.
			**
			** Everything up through dist squared should maximize
			** at 1.0, so that the distance factor is never
			** greater than one.  Conveniently, cos() is
			** never greater than one, but the same restric-
			** tion applies.
			*/
			distfactor = BETA + franf();
			distfactor *= ALPHA + b->spread;
			distfactor *= OMEGA;
			anglefactor = k->dist;
			distfactor /= anglefactor * anglefactor + EPSILON;
			distfactor *= b->units;
			dx = Ship.sectx - k->x;
			dy = k->y - Ship.secty;
			anglefactor = atan2(dy, dx) - b->angle;
			anglefactor = cos((anglefactor * b->spread) + GAMMA);
			if (anglefactor < 0.0)
			{
				k++;
				continue;
			}
			hit = anglefactor * distfactor + 0.5;
			k->power -= hit;
			printf("%d unit hit on Klingon", hit);
			if (!damaged(SRSCAN))
				printf(" at %d,%d", k->x, k->y);
			printf("\n");
			b->units -= hit;
			if (k->power <= 0)
			{
				killk(k->x, k->y);
				continue;
			}
			k++;
		}
	}

	/* compute overkill */
	for (i = 0; i < NBANKS; i++)
		extra += bank[i].units;
	if (extra > 0)
		printf("\n%d units expended on empty space\n", extra);
}