射击游戏

开发平台：
Visual C++

p_pspr.c：源码内容
							// Emacs style mode select   -*- C++ -*- 
//-----------------------------------------------------------------------------
//
// $Id:$
//
// Copyright (C) 1993-1996 by id Software, Inc.
//
// This source is available for distribution and/or modification
// only under the terms of the DOOM Source Code License as
// published by id Software. All rights reserved.
//
// The source is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// FITNESS FOR A PARTICULAR PURPOSE. See the DOOM Source Code License
// for more details.
//
// $Log:$
//
// DESCRIPTION:
//	Weapon sprite animation, weapon objects.
//	Action functions for weapons.
//
//-----------------------------------------------------------------------------
static const char
rcsid[] = "$Id: p_pspr.c,v 1.5 1997/02/03 22:45:12 b1 Exp $";
#include "doomdef.h"
#include "d_event.h"
#include "m_random.h"
#include "p_local.h"
#include "s_sound.h"
// State.
#include "doomstat.h"
// Data.
#include "sounds.h"
#include "p_pspr.h"
#define LOWERSPEED		FRACUNIT*6
#define RAISESPEED		FRACUNIT*6
#define WEAPONBOTTOM	128*FRACUNIT
#define WEAPONTOP		32*FRACUNIT
// plasma cells for a bfg attack
#define BFGCELLS		40		
//
// P_SetPsprite
//
void
P_SetPsprite
( player_t*	player,
  int		position,
  statenum_t	stnum ) 
{
    pspdef_t*	psp;
    state_t*	state;
	
    psp = &player->psprites[position];
	
    do
    {
	if (!stnum)
	{
	    // object removed itself
	    psp->state = NULL;
	    break;	
	}
	
	state = &states[stnum];
	psp->state = state;
	psp->tics = state->tics;	// could be 0
	if (state->misc1)
	{
	    // coordinate set
	    psp->sx = state->misc1 << FRACBITS;
	    psp->sy = state->misc2 << FRACBITS;
	}
	
	// Call action routine.
	// Modified handling.
	if (state->action.acp2)
	{
	    state->action.acp2(player, psp);
	    if (!psp->state)
		break;
	}
	
	stnum = psp->state->nextstate;
	
    } while (!psp->tics);
    // an initial state of 0 could cycle through
}
//
// P_CalcSwing
//	
fixed_t		swingx;
fixed_t		swingy;
void P_CalcSwing (player_t*	player)
{
    fixed_t	swing;
    int		angle;
	
    // OPTIMIZE: tablify this.
    // A LUT would allow for different modes,
    //  and add flexibility.
    swing = player->bob;
    angle = (FINEANGLES/70*leveltime)&FINEMASK;
    swingx = FixedMul ( swing, finesine[angle]);
    angle = (FINEANGLES/70*leveltime+FINEANGLES/2)&FINEMASK;
    swingy = -FixedMul ( swingx, finesine[angle]);
}
//
// P_BringUpWeapon
// Starts bringing the pending weapon up
// from the bottom of the screen.
// Uses player
//
void P_BringUpWeapon (player_t* player)
{
    statenum_t	newstate;
	
    if (player->pendingweapon == wp_nochange)
	player->pendingweapon = player->readyweapon;
		
    if (player->pendingweapon == wp_chainsaw)
	S_StartSound (player->mo, sfx_sawup);
		
    newstate = weaponinfo[player->pendingweapon].upstate;
    player->pendingweapon = wp_nochange;
    player->psprites[ps_weapon].sy = WEAPONBOTTOM; 
    P_SetPsprite (player, ps_weapon, newstate);
}
//
// P_CheckAmmo
// Returns true if there is enough ammo to shoot.
// If not, selects the next weapon to use.
//
boolean P_CheckAmmo (player_t* player)
{
    ammotype_t		ammo;
    int			count;
    ammo = weaponinfo[player->readyweapon].ammo;
    // Minimal amount for one shot varies.
    if (player->readyweapon == wp_bfg)
	count = BFGCELLS;
    else if (player->readyweapon == wp_supershotgun)
	count = 2;	// Double barrel.
    else
	count = 1;	// Regular.
    // Some do not need ammunition anyway.
    // Return if current ammunition sufficient.
    if (ammo == am_noammo || player->ammo[ammo] >= count)
	return true;
		
    // Out of ammo, pick a weapon to change to.
    // Preferences are set here.
    do
    {
	if (player->weaponowned[wp_plasma]
	    && player->ammo[am_cell]
	    && (gamemode != shareware) )
	{
	    player->pendingweapon = wp_plasma;
	}
	else if (player->weaponowned[wp_supershotgun] 
		 && player->ammo[am_shell]>2
		 && (gamemode == commercial) )
	{
	    player->pendingweapon = wp_supershotgun;
	}
	else if (player->weaponowned[wp_chaingun]
		 && player->ammo[am_clip])
	{
	    player->pendingweapon = wp_chaingun;
	}
	else if (player->weaponowned[wp_shotgun]
		 && player->ammo[am_shell])
	{
	    player->pendingweapon = wp_shotgun;
	}
	else if (player->ammo[am_clip])
	{
	    player->pendingweapon = wp_pistol;
	}
	else if (player->weaponowned[wp_chainsaw])
	{
	    player->pendingweapon = wp_chainsaw;
	}
	else if (player->weaponowned[wp_missile]
		 && player->ammo[am_misl])
	{
	    player->pendingweapon = wp_missile;
	}
	else if (player->weaponowned[wp_bfg]
		 && player->ammo[am_cell]>40
		 && (gamemode != shareware) )
	{
	    player->pendingweapon = wp_bfg;
	}
	else
	{
	    // If everything fails.
	    player->pendingweapon = wp_fist;
	}
	
    } while (player->pendingweapon == wp_nochange);
    // Now set appropriate weapon overlay.
    P_SetPsprite (player,
		  ps_weapon,
		  weaponinfo[player->readyweapon].downstate);
    return false;	
}
//
// P_FireWeapon.
//
void P_FireWeapon (player_t* player)
{
    statenum_t	newstate;
	
    if (!P_CheckAmmo (player))
	return;
	
    P_SetMobjState (player->mo, S_PLAY_ATK1);
    newstate = weaponinfo[player->readyweapon].atkstate;
    P_SetPsprite (player, ps_weapon, newstate);
    P_NoiseAlert (player->mo, player->mo);
}
//
// P_DropWeapon
// Player died, so put the weapon away.
//
void P_DropWeapon (player_t* player)
{
    P_SetPsprite (player,
		  ps_weapon,
		  weaponinfo[player->readyweapon].downstate);
}
//
// A_WeaponReady
// The player can fire the weapon
// or change to another weapon at this time.
// Follows after getting weapon up,
// or after previous attack/fire sequence.
//
void
A_WeaponReady
( player_t*	player,
  pspdef_t*	psp )
{	
    statenum_t	newstate;
    int		angle;
    
    // get out of attack state
    if (player->mo->state == &states[S_PLAY_ATK1]
	|| player->mo->state == &states[S_PLAY_ATK2] )
    {
	P_SetMobjState (player->mo, S_PLAY);
    }
    
    if (player->readyweapon == wp_chainsaw
	&& psp->state == &states[S_SAW])
    {
	S_StartSound (player->mo, sfx_sawidl);
    }
    
    // check for change
    //  if player is dead, put the weapon away
    if (player->pendingweapon != wp_nochange || !player->health)
    {
	// change weapon
	//  (pending weapon should allready be validated)
	newstate = weaponinfo[player->readyweapon].downstate;
	P_SetPsprite (player, ps_weapon, newstate);
	return;	
    }
    
    // check for fire
    //  the missile launcher and bfg do not auto fire
    if (player->cmd.buttons & BT_ATTACK)
    {
	if ( !player->attackdown
	     || (player->readyweapon != wp_missile
		 && player->readyweapon != wp_bfg) )
	{
	    player->attackdown = true;
	    P_FireWeapon (player);		
	    return;
	}
    }
    else
	player->attackdown = false;
    
    // bob the weapon based on movement speed
    angle = (128*leveltime)&FINEMASK;
    psp->sx = FRACUNIT + FixedMul (player->bob, finecosine[angle]);
    angle &= FINEANGLES/2-1;
    psp->sy = WEAPONTOP + FixedMul (player->bob, finesine[angle]);
}
//
// A_ReFire
// The player can re-fire the weapon
// without lowering it entirely.
//
void A_ReFire
( player_t*	player,
  pspdef_t*	psp )
{
    
    // check for fire
    //  (if a weaponchange is pending, let it go through instead)
    if ( (player->cmd.buttons & BT_ATTACK) 
	 && player->pendingweapon == wp_nochange
	 && player->health)
    {
	player->refire++;
	P_FireWeapon (player);
    }
    else
    {
	player->refire = 0;
	P_CheckAmmo (player);
    }
}
void
A_CheckReload
( player_t*	player,
  pspdef_t*	psp )
{
    P_CheckAmmo (player);
#if 0
    if (player->ammo[am_shell]<2)
	P_SetPsprite (player, ps_weapon, S_DSNR1);
#endif
}
//
// A_Lower
// Lowers current weapon,
//  and changes weapon at bottom.
//
void
A_Lower
( player_t*	player,
  pspdef_t*	psp )
{	
    psp->sy += LOWERSPEED;
    // Is already down.
    if (psp->sy < WEAPONBOTTOM )
	return;
    // Player is dead.
    if (player->playerstate == PST_DEAD)
    {
	psp->sy = WEAPONBOTTOM;
	// don't bring weapon back up
	return;		
    }
    
    // The old weapon has been lowered off the screen,
    // so change the weapon and start raising it
    if (!player->health)
    {
	// Player is dead, so keep the weapon off screen.
	P_SetPsprite (player,  ps_weapon, S_NULL);
	return;	
    }
	
    player->readyweapon = player->pendingweapon; 
    P_BringUpWeapon (player);
}
//
// A_Raise
//
void
A_Raise
( player_t*	player,
  pspdef_t*	psp )
{
    statenum_t	newstate;
	
    psp->sy -= RAISESPEED;
    if (psp->sy > WEAPONTOP )
	return;
    
    psp->sy = WEAPONTOP;
    
    // The weapon has been raised all the way,
    //  so change to the ready state.
    newstate = weaponinfo[player->readyweapon].readystate;
    P_SetPsprite (player, ps_weapon, newstate);
}
//
// A_GunFlash
//
void
A_GunFlash
( player_t*	player,
  pspdef_t*	psp ) 
{
    P_SetMobjState (player->mo, S_PLAY_ATK2);
    P_SetPsprite (player,ps_flash,weaponinfo[player->readyweapon].flashstate);
}
//
// WEAPON ATTACKS
//
//
// A_Punch
//
void
A_Punch
( player_t*	player,
  pspdef_t*	psp ) 
{
    angle_t	angle;
    int		damage;
    int		slope;
	
    damage = (P_Random ()%10+1)<<1;
    if (player->powers[pw_strength])	
	damage *= 10;
    angle = player->mo->angle;
    angle += (P_Random()-P_Random())<<18;
    slope = P_AimLineAttack (player->mo, angle, MELEERANGE);
    P_LineAttack (player->mo, angle, MELEERANGE, slope, damage);
    // turn to face target
    if (linetarget)
    {
	S_StartSound (player->mo, sfx_punch);
	player->mo->angle = R_PointToAngle2 (player->mo->x,
					     player->mo->y,
					     linetarget->x,
					     linetarget->y);
    }
}
//
// A_Saw
//
void
A_Saw
( player_t*	player,
  pspdef_t*	psp ) 
{
    angle_t	angle;
    int		damage;
    int		slope;
    damage = 2*(P_Random ()%10+1);
    angle = player->mo->angle;
    angle += (P_Random()-P_Random())<<18;
    
    // use meleerange + 1 se the puff doesn't skip the flash
    slope = P_AimLineAttack (player->mo, angle, MELEERANGE+1);
    P_LineAttack (player->mo, angle, MELEERANGE+1, slope, damage);
    if (!linetarget)
    {
	S_StartSound (player->mo, sfx_sawful);
	return;
    }
    S_StartSound (player->mo, sfx_sawhit);
	
    // turn to face target
    angle = R_PointToAngle2 (player->mo->x, player->mo->y,
			     linetarget->x, linetarget->y);
    if (angle - player->mo->angle > ANG180)
    {
	if (angle - player->mo->angle < -ANG90/20)
	    player->mo->angle = angle + ANG90/21;
	else
	    player->mo->angle -= ANG90/20;
    }
    else
    {
	if (angle - player->mo->angle > ANG90/20)
	    player->mo->angle = angle - ANG90/21;
	else
	    player->mo->angle += ANG90/20;
    }
    player->mo->flags |= MF_JUSTATTACKED;
}
//
// A_FireMissile
//
void
A_FireMissile
( player_t*	player,
  pspdef_t*	psp ) 
{
    player->ammo[weaponinfo[player->readyweapon].ammo]--;
    P_SpawnPlayerMissile (player->mo, MT_ROCKET);
}
//
// A_FireBFG
//
void
A_FireBFG
( player_t*	player,
  pspdef_t*	psp ) 
{
    player->ammo[weaponinfo[player->readyweapon].ammo] -= BFGCELLS;
    P_SpawnPlayerMissile (player->mo, MT_BFG);
}
//
// A_FirePlasma
//
void
A_FirePlasma
( player_t*	player,
  pspdef_t*	psp ) 
{
    player->ammo[weaponinfo[player->readyweapon].ammo]--;
    P_SetPsprite (player,
		  ps_flash,
		  weaponinfo[player->readyweapon].flashstate+(P_Random ()&1) );
    P_SpawnPlayerMissile (player->mo, MT_PLASMA);
}
//
// P_BulletSlope
// Sets a slope so a near miss is at aproximately
// the height of the intended target
//
fixed_t		bulletslope;
void P_BulletSlope (mobj_t*	mo)
{
    angle_t	an;
    
    // see which target is to be aimed at
    an = mo->angle;
    bulletslope = P_AimLineAttack (mo, an, 16*64*FRACUNIT);
    if (!linetarget)
    {
	an += 1<<26;
	bulletslope = P_AimLineAttack (mo, an, 16*64*FRACUNIT);
	if (!linetarget)
	{
	    an -= 2<<26;
	    bulletslope = P_AimLineAttack (mo, an, 16*64*FRACUNIT);
	}
    }
}
//
// P_GunShot
//
void
P_GunShot
( mobj_t*	mo,
  boolean	accurate )
{
    angle_t	angle;
    int		damage;
	
    damage = 5*(P_Random ()%3+1);
    angle = mo->angle;
    if (!accurate)
	angle += (P_Random()-P_Random())<<18;
    P_LineAttack (mo, angle, MISSILERANGE, bulletslope, damage);
}
//
// A_FirePistol
//
void
A_FirePistol
( player_t*	player,
  pspdef_t*	psp ) 
{
    S_StartSound (player->mo, sfx_pistol);
    P_SetMobjState (player->mo, S_PLAY_ATK2);
    player->ammo[weaponinfo[player->readyweapon].ammo]--;
    P_SetPsprite (player,
		  ps_flash,
		  weaponinfo[player->readyweapon].flashstate);
    P_BulletSlope (player->mo);
    P_GunShot (player->mo, !player->refire);
}
//
// A_FireShotgun
//
void
A_FireShotgun
( player_t*	player,
  pspdef_t*	psp ) 
{
    int		i;
	
    S_StartSound (player->mo, sfx_shotgn);
    P_SetMobjState (player->mo, S_PLAY_ATK2);
    player->ammo[weaponinfo[player->readyweapon].ammo]--;
    P_SetPsprite (player,
		  ps_flash,
		  weaponinfo[player->readyweapon].flashstate);
    P_BulletSlope (player->mo);
	
    for (i=0 ; i<7 ; i++)
	P_GunShot (player->mo, false);
}
//
// A_FireShotgun2
//
void
A_FireShotgun2
( player_t*	player,
  pspdef_t*	psp ) 
{
    int		i;
    angle_t	angle;
    int		damage;
		
	
    S_StartSound (player->mo, sfx_dshtgn);
    P_SetMobjState (player->mo, S_PLAY_ATK2);
    player->ammo[weaponinfo[player->readyweapon].ammo]-=2;
    P_SetPsprite (player,
		  ps_flash,
		  weaponinfo[player->readyweapon].flashstate);
    P_BulletSlope (player->mo);
	
    for (i=0 ; i<20 ; i++)
    {
	damage = 5*(P_Random ()%3+1);
	angle = player->mo->angle;
	angle += (P_Random()-P_Random())<<19;
	P_LineAttack (player->mo,
		      angle,
		      MISSILERANGE,
		      bulletslope + ((P_Random()-P_Random())<<5), damage);
    }
}
//
// A_FireCGun
//
void
A_FireCGun
( player_t*	player,
  pspdef_t*	psp ) 
{
    S_StartSound (player->mo, sfx_pistol);
    if (!player->ammo[weaponinfo[player->readyweapon].ammo])
	return;
		
    P_SetMobjState (player->mo, S_PLAY_ATK2);
    player->ammo[weaponinfo[player->readyweapon].ammo]--;
    P_SetPsprite (player,
		  ps_flash,
		  weaponinfo[player->readyweapon].flashstate
		  + psp->state
		  - &states[S_CHAIN1] );
    P_BulletSlope (player->mo);
	
    P_GunShot (player->mo, !player->refire);
}
//
// ?
//
void A_Light0 (player_t *player, pspdef_t *psp)
{
    player->extralight = 0;
}
void A_Light1 (player_t *player, pspdef_t *psp)
{
    player->extralight = 1;
}
void A_Light2 (player_t *player, pspdef_t *psp)
{
    player->extralight = 2;
}
//
// A_BFGSpray
// Spawn a BFG explosion on every monster in view
//
void A_BFGSpray (mobj_t* mo) 
{
    int			i;
    int			j;
    int			damage;
    angle_t		an;
	
    // offset angles from its attack angle
    for (i=0 ; i<40 ; i++)
    {
	an = mo->angle - ANG90/2 + ANG90/40*i;
	// mo->target is the originator (player)
	//  of the missile
	P_AimLineAttack (mo->target, an, 16*64*FRACUNIT);
	if (!linetarget)
	    continue;
	P_SpawnMobj (linetarget->x,
		     linetarget->y,
		     linetarget->z + (linetarget->height>>2),
		     MT_EXTRABFG);
	
	damage = 0;
	for (j=0;j<15;j++)
	    damage += (P_Random()&7) + 1;
	P_DamageMobj (linetarget, mo->target,mo->target, damage);
    }
}
//
// A_BFGsound
//
void
A_BFGsound
( player_t*	player,
  pspdef_t*	psp )
{
    S_StartSound (player->mo, sfx_bfg);
}
//
// P_SetupPsprites
// Called at start of level for each player.
//
void P_SetupPsprites (player_t* player) 
{
    int	i;
	
    // remove all psprites
    for (i=0 ; i<NUMPSPRITES ; i++)
	player->psprites[i].state = NULL;
		
    // spawn the gun
    player->pendingweapon = player->readyweapon;
    P_BringUpWeapon (player);
}
//
// P_MovePsprites
// Called every tic by player thinking routine.
//
void P_MovePsprites (player_t* player) 
{
    int		i;
    pspdef_t*	psp;
    state_t*	state;
	
    psp = &player->psprites[0];
    for (i=0 ; i<NUMPSPRITES ; i++, psp++)
    {
	// a null state means not active
	if ( (state = psp->state) )	
	{
	    // drop tic count and possibly change state
	    // a -1 tic count never changes
	    if (psp->tics != -1)	
	    {
		psp->tics--;
		if (!psp->tics)
		    P_SetPsprite (player, i, psp->state->nextstate);
	    }				
	}
    }
    
    player->psprites[ps_flash].sx = player->psprites[ps_weapon].sx;
    player->psprites[ps_flash].sy = player->psprites[ps_weapon].sy;
}

						