g_weapon.c

Quake 2 Source code for students by Theerthan You can also download from idsoftwares.com

/*
Copyright (C) 1997-2001 Id Software, Inc.

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, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/
#include "g_local.h"


/*
=================
check_dodge

This is a support routine used when a client is firing
a non-instant attack weapon.  It checks to see if a
monster's dodge function should be called.
=================
*/
static void check_dodge (edict_t *self, vec3_t start, vec3_t dir, int speed)
{
	vec3_t	end;
	vec3_t	v;
	trace_t	tr;
	float	eta;

	// easy mode only ducks one quarter the time
	if (skill->value == 0)
	{
		if (random() > 0.25)
			return;
	}
	VectorMA (start, 8192, dir, end);
	tr = gi.trace (start, NULL, NULL, end, self, MASK_SHOT);
	if ((tr.ent) && (tr.ent->svflags & SVF_MONSTER) && (tr.ent->health > 0) && (tr.ent->monsterinfo.dodge) && infront(tr.ent, self))
	{
		VectorSubtract (tr.endpos, start, v);
		eta = (VectorLength(v) - tr.ent->maxs[0]) / speed;
		tr.ent->monsterinfo.dodge (tr.ent, self, eta);
	}
}


/*
=================
fire_hit

Used for all impact (hit/punch/slash) attacks
=================
*/
qboolean fire_hit (edict_t *self, vec3_t aim, int damage, int kick)
{
	trace_t		tr;
	vec3_t		forward, right, up;
	vec3_t		v;
	vec3_t		point;
	float		range;
	vec3_t		dir;

	//see if enemy is in range
	VectorSubtract (self->enemy->s.origin, self->s.origin, dir);
	range = VectorLength(dir);
	if (range > aim[0])
		return false;

	if (aim[1] > self->mins[0] && aim[1] < self->maxs[0])
	{
		// the hit is straight on so back the range up to the edge of their bbox
		range -= self->enemy->maxs[0];
	}
	else
	{
		// this is a side hit so adjust the "right" value out to the edge of their bbox
		if (aim[1] < 0)
			aim[1] = self->enemy->mins[0];
		else
			aim[1] = self->enemy->maxs[0];
	}

	VectorMA (self->s.origin, range, dir, point);

	tr = gi.trace (self->s.origin, NULL, NULL, point, self, MASK_SHOT);
	if (tr.fraction < 1)
	{
		if (!tr.ent->takedamage)
			return false;
		// if it will hit any client/monster then hit the one we wanted to hit
		if ((tr.ent->svflags & SVF_MONSTER) || (tr.ent->client))
			tr.ent = self->enemy;
	}

	AngleVectors(self->s.angles, forward, right, up);
	VectorMA (self->s.origin, range, forward, point);
	VectorMA (point, aim[1], right, point);
	VectorMA (point, aim[2], up, point);
	VectorSubtract (point, self->enemy->s.origin, dir);

	// do the damage
	T_Damage (tr.ent, self, self, dir, point, vec3_origin, damage, kick/2, DAMAGE_NO_KNOCKBACK, MOD_HIT);

	if (!(tr.ent->svflags & SVF_MONSTER) && (!tr.ent->client))
		return false;

	// do our special form of knockback here
	VectorMA (self->enemy->absmin, 0.5, self->enemy->size, v);
	VectorSubtract (v, point, v);
	VectorNormalize (v);
	VectorMA (self->enemy->velocity, kick, v, self->enemy->velocity);
	if (self->enemy->velocity[2] > 0)
		self->enemy->groundentity = NULL;
	return true;
}


/*
=================
fire_lead

This is an internal support routine used for bullet/pellet based weapons.
=================
*/
static void fire_lead (edict_t *self, vec3_t start, vec3_t aimdir, int damage, int kick, int te_impact, int hspread, int vspread, int mod)
{
	trace_t		tr;
	vec3_t		dir;
	vec3_t		forward, right, up;
	vec3_t		end;
	float		r;
	float		u;
	vec3_t		water_start;
	qboolean	water = false;
	int			content_mask = MASK_SHOT | MASK_WATER;

	tr = gi.trace (self->s.origin, NULL, NULL, start, self, MASK_SHOT);
	if (!(tr.fraction < 1.0))
	{
		vectoangles (aimdir, dir);
		AngleVectors (dir, forward, right, up);

		r = crandom()*hspread;
		u = crandom()*vspread;
		VectorMA (start, 8192, forward, end);
		VectorMA (end, r, right, end);
		VectorMA (end, u, up, end);

		if (gi.pointcontents (start) & MASK_WATER)
		{
			water = true;
			VectorCopy (start, water_start);
			content_mask &= ~MASK_WATER;
		}

		tr = gi.trace (start, NULL, NULL, end, self, content_mask);

		// see if we hit water
		if (tr.contents & MASK_WATER)
		{
			int		color;

			water = true;
			VectorCopy (tr.endpos, water_start);

			if (!VectorCompare (start, tr.endpos))
			{
				if (tr.contents & CONTENTS_WATER)
				{
					if (strcmp(tr.surface->name, "*brwater") == 0)
						color = SPLASH_BROWN_WATER;
					else
						color = SPLASH_BLUE_WATER;
				}
				else if (tr.contents & CONTENTS_SLIME)
					color = SPLASH_SLIME;
				else if (tr.contents & CONTENTS_LAVA)
					color = SPLASH_LAVA;
				else
					color = SPLASH_UNKNOWN;

				if (color != SPLASH_UNKNOWN)
				{
					gi.WriteByte (svc_temp_entity);
					gi.WriteByte (TE_SPLASH);
					gi.WriteByte (8);
					gi.WritePosition (tr.endpos);
					gi.WriteDir (tr.plane.normal);
					gi.WriteByte (color);
					gi.multicast (tr.endpos, MULTICAST_PVS);
				}

				// change bullet's course when it enters water
				VectorSubtract (end, start, dir);
				vectoangles (dir, dir);
				AngleVectors (dir, forward, right, up);
				r = crandom()*hspread*2;
				u = crandom()*vspread*2;
				VectorMA (water_start, 8192, forward, end);
				VectorMA (end, r, right, end);
				VectorMA (end, u, up, end);
			}

			// re-trace ignoring water this time
			tr = gi.trace (water_start, NULL, NULL, end, self, MASK_SHOT);
		}
	}

	// send gun puff / flash
	if (!((tr.surface) && (tr.surface->flags & SURF_SKY)))
	{
		if (tr.fraction < 1.0)
		{
			if (tr.ent->takedamage)
			{
				T_Damage (tr.ent, self, self, aimdir, tr.endpos, tr.plane.normal, damage, kick, DAMAGE_BULLET, mod);
			}
			else
			{
				if (strncmp (tr.surface->name, "sky", 3) != 0)
				{
					gi.WriteByte (svc_temp_entity);
					gi.WriteByte (te_impact);
					gi.WritePosition (tr.endpos);
					gi.WriteDir (tr.plane.normal);
					gi.multicast (tr.endpos, MULTICAST_PVS);

					if (self->client)
						PlayerNoise(self, tr.endpos, PNOISE_IMPACT);
				}
			}
		}
	}

	// if went through water, determine where the end and make a bubble trail
	if (water)
	{
		vec3_t	pos;

		VectorSubtract (tr.endpos, water_start, dir);
		VectorNormalize (dir);
		VectorMA (tr.endpos, -2, dir, pos);
		if (gi.pointcontents (pos) & MASK_WATER)
			VectorCopy (pos, tr.endpos);
		else
			tr = gi.trace (pos, NULL, NULL, water_start, tr.ent, MASK_WATER);

		VectorAdd (water_start, tr.endpos, pos);
		VectorScale (pos, 0.5, pos);

		gi.WriteByte (svc_temp_entity);
		gi.WriteByte (TE_BUBBLETRAIL);
		gi.WritePosition (water_start);
		gi.WritePosition (tr.endpos);
		gi.multicast (pos, MULTICAST_PVS);
	}
}


/*
=================
fire_bullet

Fires a single round.  Used for machinegun and chaingun.  Would be fine for
pistols, rifles, etc....
=================
*/
void fire_bullet (edict_t *self, vec3_t start, vec3_t aimdir, int damage, int kick, int hspread, int vspread, int mod)
{
	fire_lead (self, start, aimdir, damage, kick, TE_GUNSHOT, hspread, vspread, mod);
}


/*
=================
fire_shotgun

Shoots shotgun pellets.  Used by shotgun and super shotgun.
=================
*/
void fire_shotgun (edict_t *self, vec3_t start, vec3_t aimdir, int damage, int kick, int hspread, int vspread, int count, int mod)
{
	int		i;

	for (i = 0; i < count; i++)
		fire_lead (self, start, aimdir, damage, kick, TE_SHOTGUN, hspread, vspread, mod);
}


/*
=================
fire_blaster

Fires a single blaster bolt.  Used by the blaster and hyper blaster.
=================
*/
void blaster_touch (edict_t *self, edict_t *other, cplane_t *plane, csurface_t *surf)
{
	int		mod;

	if (other == self->owner)
		return;

	if (surf && (surf->flags & SURF_SKY))
	{
		G_FreeEdict (self);
		return;
	}

	if (self->owner->client)
		PlayerNoise(self->owner, self->s.origin, PNOISE_IMPACT);

	if (other->takedamage)
	{
		if (self->spawnflags & 1)
			mod = MOD_HYPERBLASTER;
		else
			mod = MOD_BLASTER;
		T_Damage (other, self, self->owner, self->velocity, self->s.origin, plane->normal, self->dmg, 1, DAMAGE_ENERGY, mod);
	}
	else
	{
		gi.WriteByte (svc_temp_entity);
		gi.WriteByte (TE_BLASTER);
		gi.WritePosition (self->s.origin);
		if (!plane)
			gi.WriteDir (vec3_origin);
		else
			gi.WriteDir (plane->normal);
		gi.multicast (self->s.origin, MULTICAST_PVS);
	}

	G_FreeEdict (self);
}

void fire_blaster (edict_t *self, vec3_t start, vec3_t dir, int damage, int speed, int effect, qboolean hyper)
{
	edict_t	*bolt;
	trace_t	tr;

	VectorNormalize (dir);

	bolt = G_Spawn();
	bolt->svflags = SVF_PROJECTILE; // special net code is used for projectiles
	VectorCopy (start, bolt->s.origin);
	VectorCopy (start, bolt->s.old_origin);
	vectoangles (dir, bolt->s.angles);
	VectorScale (dir, speed, bolt->velocity);
	bolt->movetype = MOVETYPE_FLYMISSILE;
	bolt->clipmask = MASK_SHOT;
	bolt->solid = SOLID_BBOX;
	bolt->s.effects |= effect;
	VectorClear (bolt->mins);
	VectorClear (bolt->maxs);
	bolt->s.modelindex = gi.modelindex ("models/objects/laser/tris.md2");
	bolt->s.sound = gi.soundindex ("misc/lasfly.wav");
	bolt->owner = self;
	bolt->touch = blaster_touch;
	bolt->nextthink = level.time + 2;
	bolt->think = G_FreeEdict;
	bolt->dmg = damage;
	bolt->classname = "bolt";
	if (hyper)
		bolt->spawnflags = 1;
	gi.linkentity (bolt);

	if (self->client)
		check_dodge (self, bolt->s.origin, dir, speed);

	tr = gi.trace (self->s.origin, NULL, NULL, bolt->s.origin, bolt, MASK_SHOT);
	if (tr.fraction < 1.0)
	{
		VectorMA (bolt->s.origin, -10, dir, bolt->s.origin);
		bolt->touch (bolt, tr.ent, NULL, NULL);
	}
}	


/*
=================
fire_grenade
=================
*/
static void Grenade_Explode (edict_t *ent)
{
	vec3_t		origin;
	int			mod;

	if (ent->owner->client)
		PlayerNoise(ent->owner, ent->s.origin, PNOISE_IMPACT);

	//FIXME: if we are onground then raise our Z just a bit since we are a point?
	if (ent->enemy)
	{
		float	points;
		vec3_t	v;
		vec3_t	dir;

		VectorAdd (ent->enemy->mins, ent->enemy->maxs, v);
		VectorMA (ent->enemy->s.origin, 0.5, v, v);
		VectorSubtract (ent->s.origin, v, v);
		points = ent->dmg - 0.5 * VectorLength (v);
		VectorSubtract (ent->enemy->s.origin, ent->s.origin, dir);
		if (ent->spawnflags & 1)
			mod = MOD_HANDGRENADE;
		else
			mod = MOD_GRENADE;
		T_Damage (ent->enemy, ent, ent->owner, dir, ent->s.origin, vec3_origin, (int)points, (int)points, DAMAGE_RADIUS, mod);
	}

	if (ent->spawnflags & 2)
		mod = MOD_HELD_GRENADE;
	else if (ent->spawnflags & 1)
		mod = MOD_HG_SPLASH;
	else
		mod = MOD_G_SPLASH;
	T_RadiusDamage(ent, ent->owner, ent->dmg, ent->enemy, ent->dmg_radius, mod);

	VectorMA (ent->s.origin, -0.02, ent->velocity, origin);
	gi.WriteByte (svc_temp_entity);
	if (ent->waterlevel)
	{
		if (ent->groundentity)
			gi.WriteByte (TE_GRENADE_EXPLOSION_WATER);
		else
			gi.WriteByte (TE_ROCKET_EXPLOSION_WATER);
	}
	else
	{
		if (ent->groundentity)
			gi.WriteByte (TE_GRENADE_EXPLOSION);
		else
			gi.WriteByte (TE_ROCKET_EXPLOSION);
	}
	gi.WritePosition (origin);
	gi.multicast (ent->s.origin, MULTICAST_PHS);

	G_FreeEdict (ent);
}

static void Grenade_Touch (edict_t *ent, edict_t *other, cplane_t *plane, csurface_t *surf)
{
	if (other == ent->owner)
		return;

	if (surf && (surf->flags & SURF_SKY))
	{
		G_FreeEdict (ent);
		return;
	}

	if (!other->takedamage)