/*
* Empire - A multi-player, client/server Internet based war game.
- * Copyright (C) 1986-2006, Dave Pare, Jeff Bailey, Thomas Ruschak,
- * Ken Stevens, Steve McClure
+ * Copyright (C) 1986-2014, Dave Pare, Jeff Bailey, Thomas Ruschak,
+ * Ken Stevens, Steve McClure, Markus Armbruster
*
- * This program is free software; you can redistribute it and/or modify
+ * Empire is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
+ * the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* ---
*
- * See the "LEGAL", "LICENSE", "CREDITS" and "README" files for all the
- * related information and legal notices. It is expected that any future
- * projects/authors will amend these files as needed.
+ * See files README, COPYING and CREDITS in the root of the source
+ * tree for related information and legal notices. It is expected
+ * that future projects/authors will amend these files as needed.
*
* ---
*
- * landgun.c: Return values for land and ship gun firing damages
- *
+ * landgun.c: Fire weapons
+ *
* Known contributors to this file:
- *
+ * Markus Armbruster, 2006-2013
*/
#include <config.h>
-#include "misc.h"
+#include "chance.h"
+#include "damage.h"
+#include "file.h"
+#include "land.h"
+#include "nat.h"
+#include "optlist.h"
#include "prototypes.h"
+#include "sect.h"
+#include "ship.h"
-double
-landgun(int effic, int guns)
+static double
+fortgun(int effic, int guns)
{
double d;
- double g = (double)min(guns, 7);
+ double g = MIN(guns, 7);
- d = ((double)(random() % 30) + 20.0) * ((double)g / 7.0);
- d *= (double)effic;
- d /= 100.0;
+ d = (roll(30) + 19.0) * (g / 7.0);
+ d *= effic / 100.0;
return d;
}
-double
+static double
seagun(int effic, int guns)
{
double d;
d = 0.0;
while (guns--)
- d += 10.0 + (double)(random() % 6);
- d *= (double)effic * 0.01;
+ d += 9.0 + roll(6);
+ d *= effic * 0.01;
return d;
}
-double
-landunitgun(int effic, int shots, int guns, int ammo, int shells)
+static double
+landunitgun(int effic, int guns)
+{
+ double d;
+
+ d = 0.0;
+ while (guns--)
+ d += 4.0 + roll(6);
+ d *= effic * 0.01;
+ return d;
+}
+
+/*
+ * Fire from fortress SP.
+ * Use ammo, resupply if necessary.
+ * Return damage if the fortress fires, else -1.
+ */
+int
+fort_fire(struct sctstr *sp)
+{
+ int guns = sp->sct_item[I_GUN];
+
+ if (sp->sct_type != SCT_FORTR || sp->sct_effic < FORTEFF)
+ return -1;
+ if (sp->sct_item[I_MILIT] < 5 || guns == 0)
+ return -1;
+ if (!sct_supply(sp, I_SHELL, 1))
+ return -1;
+ sp->sct_item[I_SHELL]--;
+ return (int)fortgun(sp->sct_effic, guns);
+}
+
+/*
+ * Fire from ship SP.
+ * Use ammo, resupply if necessary.
+ * Return damage if the ship fires, else -1.
+ */
+int
+shp_fire(struct shpstr *sp)
{
- double d = 0.0;
+ int guns;
+
+ if (sp->shp_effic < 60)
+ return -1;
+ guns = shp_usable_guns(sp);
+ guns = MIN(guns, (sp->shp_item[I_MILIT] + 1) / 2);
+ if (guns == 0)
+ return -1;
+ shp_supply(sp, I_SHELL, (guns + 1) / 2);
+ guns = MIN(guns, sp->shp_item[I_SHELL] * 2);
+ if (guns == 0)
+ return -1;
+ sp->shp_item[I_SHELL] -= (guns + 1) / 2;
+ return (int)seagun(sp->shp_effic, guns);
+}
- shots = min(shots, guns);
- while (shots-- > 0)
- d += 5.0 + (double)(random() % 6);
- d *= (double)effic * 0.01;
- if (shells < ammo && ammo != 0)
+/*
+ * Drop depth-charges from ship SP.
+ * Use ammo, resupply if necessary.
+ * Return damage if the ship drops depth-charges, else -1.
+ */
+int
+shp_dchrg(struct shpstr *sp)
+{
+ int dchrgs;
+
+ if (sp->shp_effic < 60 || (mchr[sp->shp_type].m_flags & M_DCH) == 0)
+ return -1;
+ if (sp->shp_item[I_MILIT] == 0 || sp->shp_item[I_GUN] == 0)
+ return -1;
+ shp_supply(sp, I_SHELL, 2);
+ dchrgs = MIN(2, sp->shp_item[I_SHELL]);
+ if (dchrgs == 0)
+ return -1;
+ sp->shp_item[I_SHELL] -= dchrgs;
+ return (int)seagun(sp->shp_effic, 2 * dchrgs - 1);
+}
+
+/*
+ * Fire torpedo from ship SP.
+ * Use ammo and mobility, resupply if necessary.
+ * Return damage if the ship fires, else -1.
+ */
+int
+shp_torp(struct shpstr *sp, int usemob)
+{
+ if (sp->shp_effic < 60 || (mchr[sp->shp_type].m_flags & M_TORP) == 0)
+ return -1;
+ if (sp->shp_item[I_MILIT] == 0 || sp->shp_item[I_GUN] == 0)
+ return -1;
+ if (usemob && sp->shp_mobil <= 0)
+ return -1;
+ if (!shp_supply(sp, I_SHELL, SHP_TORP_SHELLS))
+ return -1;
+ sp->shp_item[I_SHELL] -= SHP_TORP_SHELLS;
+ if (usemob)
+ sp->shp_mobil -= (int)shp_mobcost(sp) / 2.0;
+ return TORP_DAMAGE();
+}
+
+/*
+ * Fire from land unit LP.
+ * Use ammo, resupply if necessary.
+ * Return damage if the land unit fires, else -1.
+ */
+int
+lnd_fire(struct lndstr *lp)
+{
+ int guns, ammo, shells;
+ double d;
+
+ if (lp->lnd_effic < LAND_MINFIREEFF)
+ return -1;
+ if (lp->lnd_ship >= 0 || lp->lnd_land >= 0)
+ return -1;
+ if (lp->lnd_item[I_MILIT] == 0)
+ return -1;
+ guns = lnd_dam(lp);
+ guns = MIN(guns, lp->lnd_item[I_GUN]);
+ if (guns == 0)
+ return -1;
+ ammo = lchr[lp->lnd_type].l_ammo;
+ if (CANT_HAPPEN(ammo == 0))
+ ammo = 1;
+ lnd_supply(lp, I_SHELL, ammo);
+ shells = lp->lnd_item[I_SHELL];
+ if (shells == 0)
+ return -1;
+ d = landunitgun(lp->lnd_effic, guns);
+ if (shells < ammo) {
d *= (double)shells / (double)ammo;
+ ammo = shells;
+ }
+ lp->lnd_item[I_SHELL] -= ammo;
return d;
}
+/*
+ * Sabotage with land unit LP.
+ * Use ammo.
+ * Return damage if the land unit sabotages, else -1.
+ */
int
-roundrange(double r)
+lnd_sabo(struct lndstr *lp, short item[])
+{
+ int dam;
+
+ if (lp->lnd_ship >= 0 || lp->lnd_land >= 0)
+ return -1;
+ if (!(lchr[lp->lnd_type].l_flags & L_SPY))
+ return -1;
+ if (!lp->lnd_item[I_SHELL])
+ return -1;
+ lp->lnd_item[I_SHELL]--;
+ dam = fortgun(3 * lp->lnd_effic, 7);
+ if (item[I_SHELL] > 20)
+ dam += seagun(lp->lnd_effic, roll0(item[I_SHELL] / 10));
+ if (item[I_PETROL] > 100)
+ dam += seagun(lp->lnd_effic, roll0(item[I_PETROL] / 50));
+ return dam;
+}
+
+/*
+ * Return number of guns ship SP can fire.
+ */
+int
+shp_usable_guns(struct shpstr *sp)
+{
+ return MIN(shp_glim(sp), sp->shp_item[I_GUN]);
+}
+
+/*
+ * Return effective firing range for range factor RNG at tech TLEV.
+ */
+static double
+effrange(int rng, double tlev)
+{
+ /* FIXME don't truncate TLEV */
+ return techfact((int)tlev, rng / 2.0);
+}
+
+/*
+ * Return firing range for sector SP.
+ */
+double
+fortrange(struct sctstr *sp)
{
- double f;
+ struct natstr *np = getnatp(sp->sct_own);
+ double rng;
+
+ if (sp->sct_type != SCT_FORTR || sp->sct_effic < FORTEFF)
+ return -1.0;
- f = r - (int)r;
- if (chance(f))
- return (int)r + 1;
- else
- return (int)r;
+ rng = effrange(14.0 * fire_range_factor, np->nat_level[NAT_TLEV]);
+ if (sp->sct_effic >= 60)
+ rng++;
+ return rng;
+}
+
+/*
+ * Return firing range for ship SP.
+ */
+double
+shp_fire_range(struct shpstr *sp)
+{
+ return effrange(shp_frnge(sp), sp->shp_tech);
+}
+
+/*
+ * Return torpedo range for ship SP.
+ */
+double
+torprange(struct shpstr *sp)
+{
+ return effrange(shp_frnge(sp) * 2, sp->shp_tech)
+ * sp->shp_effic / 100.0;
+}
+
+/*
+ * Return hit chance for torpedo from ship SP at range RANGE.
+ */
+double
+shp_torp_hitchance(struct shpstr *sp, int range)
+{
+ return DTORP_HITCHANCE(range, shp_visib(sp));
+}
+
+/*
+ * Return firing range for land unit SP.
+ */
+double
+lnd_fire_range(struct lndstr *lp)
+{
+ return effrange(lnd_frg(lp), lp->lnd_tech);
+}
+
+int
+roundrange(double r)
+{
+ return roundavg(r);
}