p_inter.c

//
// Copyright (C) 1993-1996 Id Software, Inc.
// Copyright (C) 2023 Frenkel Smeijers
//
// This program 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 (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// 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, see <https://www.gnu.org/licenses/>.
//

// P_inter.c

#include "doomdef.h"
#include "p_local.h"
#include "soundst.h"

#define BONUSADD 6

// a weapon is found with two clip loads, a big item has five clip loads
int32_t		maxammo[NUMAMMO] = {200, 50, 300, 50};
static const int32_t		clipammo[NUMAMMO] = {10, 4, 20, 1};


/*
===============================================================================
							GET STUFF
===============================================================================
*/

/* 
=================== 
= 
= P_GiveAmmo
=
= Num is the number of clip loads, not the individual count (0= 1/2 clip)
= Returns false if the ammo can't be picked up at all
=================== 
*/ 

static boolean P_GiveAmmo (player_t *player, ammotype_t ammo, int32_t num)
{
	int32_t		oldammo;
	
	if (ammo == am_noammo)
		return false;
		
	if (ammo < 0 || ammo > NUMAMMO)
		I_Error ("P_GiveAmmo: bad type %i", ammo);
		
	if ( player->ammo[ammo] == player->maxammo[ammo]  )
		return false;
			
	if (num)
		num *= clipammo[ammo];
	else
		num = clipammo[ammo]/2;
	if (gameskill == sk_baby || gameskill == sk_nightmare)
		num <<= 1;			// give double ammo in trainer mode, you'll need in nightmare
		
	oldammo = player->ammo[ammo];
	player->ammo[ammo] += num;
	if (player->ammo[ammo] > player->maxammo[ammo])
		player->ammo[ammo] = player->maxammo[ammo];
	
	if (oldammo)
		return true;		// don't change up weapons, player was lower on
							// purpose

	switch (ammo)
	{
	case am_clip:
		if (player->readyweapon == wp_fist)
		{
			if (player->weaponowned[wp_chaingun])
				player->pendingweapon = wp_chaingun;
			else
				player->pendingweapon = wp_pistol;
		}
		break;
	case am_shell:
		if (player->readyweapon == wp_fist || player->readyweapon == wp_pistol)
		{
			if (player->weaponowned[wp_shotgun])
				player->pendingweapon = wp_shotgun;
		}
		break;
	case am_cell:
		if (player->readyweapon == wp_fist || player->readyweapon == wp_pistol)
		{
			if (player->weaponowned[wp_plasma])
				player->pendingweapon = wp_plasma;
		}
		break;
	case am_misl:
		if (player->readyweapon == wp_fist)
		{
			if (player->weaponowned[wp_missile])
				player->pendingweapon = wp_missile;
		}
	default:
		break;
	}
	
	return true;
}


/* 
=================== 
= 
= P_GiveWeapon
=
= The weapon name may have a MF_DROPPED flag ored in
=================== 
*/ 

static boolean P_GiveWeapon (player_t *player, weapontype_t weapon, boolean dropped)
{
	boolean		gaveammo, gaveweapon;
	
	if (netgame && (deathmatch!=2) && !dropped)
	{	// leave placed weapons forever on cooperative net games
		if (player->weaponowned[weapon])
			return false;
		player->bonuscount += BONUSADD;
		player->weaponowned[weapon] = true;
		if (deathmatch)
			P_GiveAmmo (player, weaponinfo[weapon].ammo, 5);
		else
			P_GiveAmmo (player, weaponinfo[weapon].ammo, 2);
		player->pendingweapon = weapon;
		if (player == &players[consoleplayer])
			S_StartSound (NULL, sfx_wpnup);
		return false;
	}
	
	if (weaponinfo[weapon].ammo != am_noammo)
	{	// give one clip with a dropped weapon, two clips with a found weapon
		if (dropped)
			gaveammo = P_GiveAmmo (player, weaponinfo[weapon].ammo, 1);
		else
			gaveammo = P_GiveAmmo (player, weaponinfo[weapon].ammo, 2);
	}
	else
		gaveammo = false;
	
	if (player->weaponowned[weapon])
		gaveweapon = false;
	else
	{
		gaveweapon = true;
		player->weaponowned[weapon] = true;
		player->pendingweapon = weapon;
	}
	
	return (gaveweapon || gaveammo);
}



/* 
=================== 
= 
= P_GiveBody
=
= Returns false if the body isn't needed at all
=================== 
*/ 

static boolean P_GiveBody (player_t *player, int32_t num)
{
	if (player->health >= MAXHEALTH)
		return false;
		
	player->health += num;
	if (player->health > MAXHEALTH)
		player->health = MAXHEALTH;
	player->mo->health = player->health;
	
	return true;
}


/* 
=================== 
= 
= P_GiveArmor
=
= Returns false if the armor is worse than the current armor
=================== 
*/ 

static boolean P_GiveArmor (player_t *player, int32_t armortype)
{
	int32_t		hits;
	
	hits = armortype*100;
	if (player->armorpoints >= hits)
		return false;		// don't pick up
		
	player->armortype = armortype;
	player->armorpoints = hits;
	
	return true;
}


/* 
=================== 
= 
= P_GiveCard
=
=================== 
*/ 

static void P_GiveCard (player_t *player, card_t card)
{
	if (player->cards[card])
		return;		
	player->bonuscount = BONUSADD;
	player->cards[card] = 1;
}


/* 
=================== 
= 
= P_GivePower
=
=================== 
*/ 

boolean P_GivePower (player_t *player, powertype_t power)
{
	if (power == pw_invulnerability)
	{
		player->powers[power] = INVULNTICS;
		return true;
	}
	if (power == pw_invisibility)
	{
		player->powers[power] = INVISTICS;
		player->mo->flags |= MF_SHADOW;
		return true;
	}
	if (power == pw_infrared)
	{
		player->powers[power] = INFRATICS;
		return true;
	}
	if (power == pw_ironfeet)
	{
		player->powers[power] = IRONTICS;
		return true;
	}
	if (power == pw_strength)
	{
		P_GiveBody (player, 100);
		player->powers[power] = 1;
		return true;
	}
	
	if (player->powers[power])
		return false;		// already got it
		
	player->powers[power] = 1;
	return true;
}



/*
==================
=
= P_TouchSpecialThing
=
==================
*/

void P_TouchSpecialThing (mobj_t *special, mobj_t *toucher)
{
	player_t	*player;
	int32_t		i;
	fixed_t		delta;
	int32_t		sound;
		
	delta = special->z - toucher->z;
	if (delta > toucher->height || delta < -8*FRACUNIT)
		return;			// out of reach
	
	sound = sfx_itemup;	
	player = toucher->player;
	if (toucher->health <= 0)
		return;						// can happen with a sliding player corpse
	switch (special->sprite)
	{
//
// armor
//
	case SPR_ARM1:
		if (!P_GiveArmor (player, 1))
			return;
		player->message = GOTARMOR;
		break;
	case SPR_ARM2:
		if (!P_GiveArmor (player, 2))
			return;
		player->message = GOTMEGA;
		break;


//
// bonus items
//
	case SPR_BON1:
		player->health++;		// can go over 100%
		if (player->health > 200)
			player->health = 200;
		player->mo->health = player->health;
		player->message = GOTHTHBONUS;
		break;
	case SPR_BON2:
		player->armorpoints++;		// can go over 100%
		if (player->armorpoints > 200)
			player->armorpoints = 200;
		if (!player->armortype)
			player->armortype = 1;
		player->message = GOTARMBONUS;
		break;
	case SPR_SOUL:
		player->health += 100;
		if (player->health > 200)
			player->health = 200;
		player->mo->health = player->health;
		player->message = GOTSUPER;
		sound = sfx_getpow;
		break;
	case SPR_MEGA:
		if (!commercial)
			return;
		player->health = 200;
		player->mo->health = player->health;
		P_GiveArmor (player,2);
		player->message = GOTMSPHERE;
		sound = sfx_getpow;
		break;
				

//
// cards
// leave cards for everyone
	case SPR_BKEY:
		if (!player->cards[it_bluecard])
			player->message = GOTBLUECARD;
		P_GiveCard (player, it_bluecard);
		if (!netgame)
			break;
		return;
	case SPR_YKEY:
		if (!player->cards[it_yellowcard])
			player->message = GOTYELWCARD;
		P_GiveCard (player, it_yellowcard);
		if (!netgame)
			break;
		return;
	case SPR_RKEY:
		if (!player->cards[it_redcard])
			player->message = GOTREDCARD;
		P_GiveCard (player, it_redcard);
		if (!netgame)
			break;
		return;
	case SPR_BSKU:
		if (!player->cards[it_blueskull])
			player->message = GOTBLUESKUL;
		P_GiveCard (player, it_blueskull);
		if (!netgame)
			break;
		return;
	case SPR_YSKU:
		if (!player->cards[it_yellowskull])
			player->message = GOTYELWSKUL;
		P_GiveCard (player, it_yellowskull);
		if (!netgame)
			break;
		return;
	case SPR_RSKU:
		if (!player->cards[it_redskull])
			player->message = GOTREDSKULL;
		P_GiveCard (player, it_redskull);
		if (!netgame)
			break;
		return;


//
// medikits, heals
//
	case SPR_STIM:
		if (!P_GiveBody (player, 10))
			return;
		player->message = GOTSTIM;
		break;
	case SPR_MEDI:
		if (!P_GiveBody (player, 25))
			return;
		if (player->health < 25)
			player->message = GOTMEDINEED;
		else
			player->message = GOTMEDIKIT;
		break;
	

//
// power ups
//
	case SPR_PINV:
		if (!P_GivePower (player, pw_invulnerability))
			return;
		player->message = GOTINVUL;
		sound = sfx_getpow;
		break;
	case SPR_PSTR:
		if (!P_GivePower (player, pw_strength))
			return;
		player->message = GOTBERSERK;
		if (player->readyweapon != wp_fist)
			player->pendingweapon = wp_fist;
		sound = sfx_getpow;
		break;
	case SPR_PINS:
		if (!P_GivePower (player, pw_invisibility))
			return;
		player->message = GOTINVIS;
		sound = sfx_getpow;
		break;
	case SPR_SUIT:
		if (!P_GivePower (player, pw_ironfeet))
			return;
		player->message = GOTSUIT;
		sound = sfx_getpow;
		break;
	case SPR_PMAP:
		if (!P_GivePower (player, pw_allmap))
			return;
		player->message = GOTMAP;
		sound = sfx_getpow;
		break;
	case SPR_PVIS:
		if (!P_GivePower (player, pw_infrared))
			return;
		player->message = GOTVISOR;
		sound = sfx_getpow;
		break;
		

//
// ammo
//
	case SPR_CLIP:
		if (special->flags & MF_DROPPED)
		{
			if (!P_GiveAmmo (player,am_clip,0))
				return;
		}
		else
		{
			if (!P_GiveAmmo (player,am_clip,1))
				return;
		}
		player->message = GOTCLIP;
		break;
	case SPR_AMMO:
		if (!P_GiveAmmo (player, am_clip,5))
			return;
		player->message = GOTCLIPBOX;
		break;
	case SPR_ROCK:
		if (!P_GiveAmmo (player, am_misl,1))
			return;
		player->message = GOTROCKET;
		break;	
	case SPR_BROK:
		if (!P_GiveAmmo (player, am_misl,5))
			return;
		player->message = GOTROCKBOX;
		break;
	case SPR_CELL:
		if (!P_GiveAmmo (player, am_cell,1))
			return;
		player->message = GOTCELL;
		break;
	case SPR_CELP:
		if (!P_GiveAmmo (player, am_cell,5))
			return;
		player->message = GOTCELLBOX;
		break;
	case SPR_SHEL:
		if (!P_GiveAmmo (player, am_shell,1))
			return;
		player->message = GOTSHELLS;
		break;
	case SPR_SBOX:
		if (!P_GiveAmmo (player, am_shell,5))
			return;
		player->message = GOTSHELLBOX;
		break;		
	case SPR_BPAK:
		if (!player->backpack)
		{
			for (i=0 ; i<NUMAMMO ; i++)
				player->maxammo[i] *= 2;
			player->backpack = true;
		}
		for (i=0 ; i<NUMAMMO ; i++)
			P_GiveAmmo (player, i, 1);
		player->message = GOTBACKPACK;
		break;

		
//
// weapons
//
	case SPR_BFUG:
		if (!P_GiveWeapon (player, wp_bfg, false) )
			return;
		player->message = GOTBFG9000;
		sound = sfx_wpnup;	
		break;
	case SPR_MGUN:
		if (!P_GiveWeapon (player, wp_chaingun, special->flags&MF_DROPPED) )
			return;
		player->message = GOTCHAINGUN;
		sound = sfx_wpnup;	
		break;
	case SPR_CSAW:
		if (!P_GiveWeapon (player, wp_chainsaw, false) )
			return;
		player->message = GOTCHAINSAW;
		sound = sfx_wpnup;	
		break;
	case SPR_LAUN:
		if (!P_GiveWeapon (player, wp_missile, false) )
			return;
		player->message = GOTLAUNCHER;
		sound = sfx_wpnup;	
		break;
	case SPR_PLAS:
		if (!P_GiveWeapon (player, wp_plasma, false) )
			return;
		player->message = GOTPLASMA;
		sound = sfx_wpnup;	
		break;
	case SPR_SHOT:
		if (!P_GiveWeapon (player, wp_shotgun, special->flags&MF_DROPPED ) )
			return;
		player->message = GOTSHOTGUN;
		sound = sfx_wpnup;	
		break;
	case SPR_SGN2:
		if (!P_GiveWeapon (player, wp_supershotgun, special->flags&MF_DROPPED ) )
			return;
		player->message = GOTSHOTGUN2;
		sound = sfx_wpnup;	
		break;
		
	default:
		I_Error ("P_SpecialThing: Unknown gettable thing");
	}
	
	if (special->flags & MF_COUNTITEM)
		player->itemcount++;
	P_RemoveMobj (special);
	player->bonuscount += BONUSADD;
	if (player == &players[consoleplayer])
		S_StartSound (NULL, sound);
}

/*
==============
=
= KillMobj
=
==============
*/

static void P_KillMobj (mobj_t *source, mobj_t *target)
{
	mobjtype_t		item;
	mobj_t			*mo;
	
	target->flags &= ~(MF_SHOOTABLE|MF_FLOAT|MF_SKULLFLY);
	if (target->type != MT_SKULL)
		target->flags &= ~MF_NOGRAVITY;
	target->flags |= MF_CORPSE|MF_DROPOFF;
	target->height >>= 2;

	if (source && source->player)
	{
		if (target->flags & MF_COUNTKILL)
			source->player->killcount++;	// count for intermission

		if (target->player)
			source->player->frags[target->player-players]++;
	}
	else if (!netgame && (target->flags & MF_COUNTKILL) )
		players[0].killcount++;			// count all monster deaths, even
										// those caused by other monsters
	
	if (target->player)
	{
		if (!source)	// count environment kills against you
			target->player->frags[target->player-players]++;
		target->flags &= ~MF_SOLID;
		target->player->playerstate = PST_DEAD;
		P_DropWeapon (target->player);

		if (target->player == &players[consoleplayer] && automapactive)
			AM_Stop ();					// don't die in auto map,
										// switch view prior to dying
	}

	if (target->health < -target->info->spawnhealth 
	&& target->info->xdeathstate)
		P_SetMobjState (target, target->info->xdeathstate);
	else
		P_SetMobjState (target, target->info->deathstate);
	target->tics -= P_Random()&3;
	if (target->tics < 1)
		target->tics = 1;
		
#if !APPVER_CHEX
//
// drop stuff
//
	switch (target->type)
	{
	case MT_WOLFSS:
	case MT_POSSESSED:
		item = MT_CLIP;
		break;
	case MT_SHOTGUY:
		item = MT_SHOTGUN;
		break;
	case MT_CHAINGUY:
		item = MT_CHAINGUN;
		break;
	default:
		return;
	}

	mo = P_SpawnMobj (target->x,target->y,ONFLOORZ, item);
	mo->flags |= MF_DROPPED;		// special versions of items
#endif
}



/*
=================
=
= P_DamageMobj
=
= Damages both enemies and players
= inflictor is the thing that caused the damage
= 		creature or missile, can be NULL (slime, etc)
= source is the thing to target after taking damage
=		creature or NULL
= Source and inflictor are the same for melee attacks
= source can be null for barrel explosions and other environmental stuff
==================
*/

void P_DamageMobj (mobj_t *target, mobj_t *inflictor, mobj_t *source, int32_t damage)
{
	uint32_t	ang;
	int32_t		saved;
	player_t	*player;
	fixed_t		thrust;
		
	if ( !(target->flags & MF_SHOOTABLE) )
		return;						// shouldn't happen...
		
	if (target->health <= 0)
		return;

	if ( target->flags & MF_SKULLFLY )
	{
		target->momx = target->momy = target->momz = 0;
	}
	
	player = target->player;
	if (player && gameskill == sk_baby)
		damage >>= 1;				// take half damage in trainer mode

//
// kick away unless using the chainsaw
//
	if (inflictor && !(target->flags & MF_NOCLIP) && (!source || !source->player
	|| source->player->readyweapon != wp_chainsaw))
	{
		ang = R_PointToAngle2 ( inflictor->x, inflictor->y
			,target->x, target->y);
		
		thrust = damage*(FRACUNIT>>3)*100/target->info->mass;

		// make fall forwards sometimes
		if ( damage < 40 && damage > target->health && target->z - inflictor->z > 64*FRACUNIT && (P_Random ()&1) )
		{
			ang += ANG180;
			thrust *= 4;
		}
		
		ang >>= ANGLETOFINESHIFT;
		target->momx += FixedMul (thrust, finecosine[ang]);
		target->momy += FixedMul (thrust, finesine[ang]);
	}
	
//
// player specific
//
	if (player)
	{
		// end of game hell hack
		if (target->subsector->sector->special == 11
			&& damage >= target->health)
		{
			damage = target->health - 1;
		}

		if ( damage < 1000 && ((player->cheats&CF_GODMODE)
			|| player->powers[pw_invulnerability] ) )
		{
			return;
		}

		if (player->armortype)
		{
			if (player->armortype == 1)
				saved = damage/3;
			else
				saved = damage/2;
			if (player->armorpoints <= saved)
			{	// armor is used up
				saved = player->armorpoints;
				player->armortype = 0;
			}
			player->armorpoints -= saved;
			damage -= saved;
		}
		player->health -= damage;		// mirror mobj health here for Dave
		if (player->health < 0)
			player->health = 0;
		player->attacker = source;
		player->damagecount += damage;	// add damage after armor / invuln
		if (player->damagecount > 100)
			player->damagecount = 100;	// teleport stomp does 10k points...
	}

//
// do the damage
//	
	target->health -= damage;	
	if (target->health <= 0)
	{
		P_KillMobj (source, target);
		return;
	}

	if ( (P_Random () < target->info->painchance) && !(target->flags&MF_SKULLFLY) )
	{
		target->flags |= MF_JUSTHIT;		// fight back!
		P_SetMobjState (target, target->info->painstate);
	}
			
	target->reactiontime = 0;		// we're awake now...	
	if ( (!target->threshold || target->type == MT_VILE)
		&& source && source != target && source->type != MT_VILE )
	{	// if not intent on another player, chase after this one
		target->target = source;
		target->threshold = BASETHRESHOLD;
		if (target->state == &states[target->info->spawnstate]
		&& target->info->seestate != S_NULL)
			P_SetMobjState (target, target->info->seestate);
	}

}