thirtyflightsofloving/game/g_jetpack.c

/*
===========================================================================
Copyright (C) 1997-2001 Id Software, Inc.
Copyright (C) 2000-2002 Mr. Hyde and Mad Dog

This file is part of Lazarus Quake 2 Mod source code.

Lazarus Quake 2 Mod source code 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.

Lazarus Quake 2 Mod source code 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 Lazarus Quake 2 Mod source code; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
===========================================================================
*/

#include "g_local.h"

#ifdef JETPACK_MOD
/*we get silly velocity-effects when we are on ground and try to
  accelerate, so lift us a little bit if possible*/
qboolean Jet_AvoidGround( edict_t *ent )
{
	vec3_t		new_origin;
	trace_t	trace;
	qboolean	success;

/*Check if there is enough room above us before we change origin[2]*/

	new_origin[0] = ent->s.origin[0];
	new_origin[1] = ent->s.origin[1];
	new_origin[2] = ent->s.origin[2] + 0.5;
	trace = gi.trace( ent->s.origin, ent->mins, ent->maxs, new_origin, ent, MASK_PLAYERSOLID );
	if ( success=(trace.plane.normal[2]==0) )
		/*no ceiling?*/
		ent->s.origin[2] += 0.5;
		/*then make sure off ground*/
	return success;
}

/*If a player dies with activated jetpack this function will be called
and produces a little explosion*/

void Jet_BecomeExplosion( edict_t *ent, int damage )
{
	gi.WriteByte( svc_temp_entity );
	gi.WriteByte( TE_EXPLOSION1 );
	/*TE_EXPLOSION2 is possible too*/
	gi.WritePosition( ent->s.origin );
	gi.multicast( ent->s.origin, MULTICAST_PVS );
	gi.sound( ent, CHAN_BODY, gi.soundindex("misc/udeath.wav"), 1, ATTN_NORM, 0 );

	if (level.num_reflectors)
		ReflectExplosion (TE_EXPLOSION1, ent->s.origin);

// Lazarus: NO! This is taken care of already in player_die
	/*throw some gib*/
/*	for ( n=0; n<4; n++ )
		ThrowGib( ent, "models/objects/gibs/sm_meat/tris.md2", damage, GIB_ORGANIC );
	ThrowClientHead( ent, damage ); */
	ent->takedamage = DAMAGE_NO;
}

/*The lifting effect is done through changing the origin, it
gives the best results. Of course its a little dangerous because
if we dont take care, we can move into solid*/

void Jet_ApplyLifting( edict_t *ent )
{
	float		delta;
	vec3_t	new_origin;
	trace_t	trace;
	int 		time = 24;
	/*must be >0, time/10 = time in sec for a complete cycle (up/down)*/
	float		amplitude = 2.0;
	/*calculate the z-distance to lift in this step*/
	delta = sin( (float)((level.framenum%time)*(360/time))/180*M_PI ) * amplitude;
	delta = (float)((int)(delta*8))/8; /*round to multiples of 0.125*/
	VectorCopy( ent->s.origin, new_origin );
	new_origin[2] += delta;
	if( VectorLength(ent->velocity) == 0 )
	{
		/*i dont know the reason yet, but there is some floating so we
		have to compensate that here (only if there is no velocity left)*/
		new_origin[0] -= 0.125;
		new_origin[1] -= 0.125;
		new_origin[2] -= 0.125;
	}
	/*before we change origin, its important to check that we dont go
	into solid*/
	trace = gi.trace( ent->s.origin, ent->mins, ent->maxs, new_origin, ent, MASK_MONSTERSOLID );
	if ( trace.plane.normal[2] == 0 )
		VectorCopy( new_origin, ent->s.origin );
}

/*This function applys some sparks to your jetpack*/

void Jet_ApplySparks ( edict_t *ent )
{
	vec3_t  forward, right;
	vec3_t  pack_pos, jet_vector;
	AngleVectors(ent->client->v_angle, forward, right, NULL);
	VectorScale (forward, -8, pack_pos);
	VectorAdd (pack_pos, ent->s.origin, pack_pos);
	pack_pos[2] += 6;
	VectorScale (forward, -50, jet_vector);
	gi.WriteByte (svc_temp_entity);
	gi.WriteByte (TE_SPARKS);
	gi.WritePosition (pack_pos);
	gi.WriteDir (jet_vector);
	gi.multicast (pack_pos, MULTICAST_PVS);

	if(level.num_reflectors)
		ReflectSparks(TE_SPARKS,pack_pos,jet_vector);
}

/*Now for the main movement code. The steering is a lot like in water, that
means your viewing direction is your moving direction. You have three
direction Boosters: the big Main Booster and the smaller up-down and
left-right Boosters.
There are only 2 adds to the code of the first tutorial: the jetpack_nextthink
and the rolling.
The other modifications results in the use of the built-in quake functions,
there is no change in moving behavior (reinventing the wheel is a lot of
"fun" and a BIG waste of time ;-))*/

void Jet_ApplyJet( edict_t *ent, usercmd_t *ucmd )
{
	float	direction;
	float	scale;
	vec3_t	acc;
	vec3_t	forward, right;

	/*clear gravity so we dont have to compensate it with the Boosters*/
	ent->client->ps.pmove.gravity = 0;

	/*calculate the direction vectors dependent on viewing direction
	(length of the vectors forward/right is always 1, the coordinates of
	the vectors are values of how much youre looking in a specific direction
	[if youre looking up to the top, the x/y values are nearly 0 the
	z value is nearly 1])*/
	AngleVectors( ent->client->v_angle, forward, right, NULL );
	/*Run jet only 10 times a second so movement doesn't depend on fps
	because ClientThink is called as often as possible
	(fps<10 still is a problem ?)*/
	if ( ent->client->jetpack_nextthink <= level.framenum )
	{
		ent->client->jetpack_nextthink = level.framenum + 1;
	    /*clear acceleration-vector*/
		VectorClear( acc );
		/*if we are moving forward or backward add MainBooster acceleration
		(60)*/
		if ( ucmd->forwardmove )
		{
			/*are we accelerating backward or forward?*/
			direction = (ucmd->forwardmove<0) ? -1.0 : 1.0;
			/*add the acceleration for each direction*/
			if(jetpack_weenie->value)
			{
				acc[0] += forward[0] * direction * 60;
				acc[1] += forward[1] * direction * 60;
				acc[2] += forward[2] * direction * 60;
			}
			else
			{
				acc[0] += forward[0] * direction * 120;
				acc[1] += forward[1] * direction * 120;
			}
		}
	    /*if we sidestep add Left-Right-Booster acceleration (40)*/
	    if ( ucmd->sidemove )
		{      /*are we accelerating left or right*/
			direction = (ucmd->sidemove<0) ? -1.0 : 1.0;
			/*add only to x and y acceleration*/
			if(jetpack_weenie->value)
				scale = direction * 40;
			else
				scale = direction * 80;
			acc[0] += right[0] * scale;
			acc[1] += right[1] * scale;
		}

	    /*if we crouch or jump add Up-Down-Booster acceleration (30)*/
	    if ( ucmd->upmove )
		{
			if(jetpack_weenie->value)
				scale = 30;
			else
				scale = 45;
			acc[2] += ucmd->upmove > 0 ? scale : -scale;
		}
	    /*now apply some friction dependent on velocity (higher velocity results
		in higher friction), without acceleration this will reduce the velocity
		to 0 in a few steps*/
		ent->velocity[0] *= 0.83;
	    ent->velocity[1] *= 0.83;
		ent->velocity[2] *= 0.86;
	    /*then accelerate with the calculated values. If the new acceleration for
		a direction is smaller than an earlier, the friction will reduce the speed
		in that direction to the new value in a few steps, so if youre flying
		curves or around corners youre floating a little bit in the old direction*/
	    VectorAdd( ent->velocity, acc, ent->velocity );
		/*round velocitys (is this necessary?)*/
	    ent->velocity[0] = (float)((int)(ent->velocity[0]*8))/8;
		ent->velocity[1] = (float)((int)(ent->velocity[1]*8))/8;
	    ent->velocity[2] = (float)((int)(ent->velocity[2]*8))/8;
		/*Bound X and Y velocity so that friction and acceleration dont need to be
		synced on maxvelocitys*/
		if(jetpack_weenie->value)
		{
			if(ent->velocity[0] >  300) ent->velocity[0] =  300;
			if(ent->velocity[0] < -300) ent->velocity[0] = -300;
			if(ent->velocity[1] >  300) ent->velocity[1] =  300;
			if(ent->velocity[1] < -300) ent->velocity[1] = -300;
		}
		else
		{
			if(ent->velocity[0] >  1000) ent->velocity[0] =  1000;
			if(ent->velocity[0] < -1000) ent->velocity[0] = -1000;
			if(ent->velocity[1] >  1000) ent->velocity[1] =  1000;
			if(ent->velocity[1] < -1000) ent->velocity[1] = -1000;
		}
	    /*add some gentle up and down when idle (not accelerating)*/
		if( (VectorLength(acc) == 0) && (!ent->groundentity))
			Jet_ApplyLifting( ent );
	} //if ( ent->client->jetpack_nextthink...
	/*add rolling when we fly curves or boost left/right*/
	if((bob_roll->value > 0) && (jetpack_weenie->value || !ent->groundentity))
	{
		ent->client->kick_angles[ROLL] = -DotProduct( ent->velocity, right ) * ent->client->jetpack_roll;
		if(ucmd->sidemove)
			ent->client->jetpack_roll = min(0.02,ent->client->jetpack_roll + 0.002);
		else
			ent->client->jetpack_roll = max(0.00,ent->client->jetpack_roll - 0.002);
	}
	else
		ent->client->jetpack_roll = 0;
	/*last but not least add some smoke*/
	Jet_ApplySparks( ent );

//	gi.dprintf("%5g %5g %5g\n",ent->velocity[0],ent->velocity[1],ent->velocity[2]);
}
#endif