/*
	sw_rpart.c

	(description)

	Copyright (C) 1996-1997  Id Software, Inc.
	Copyright (C) 1999,2000  Nelson Rush.
	Copyright (C) 1999,2000  contributors of the QuakeForge project
	Please see the file "AUTHORS" for a list of contributors

	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:

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

	$Id$
*/

#include <quakedef.h>
#include <r_local.h>

#include <d_iface.h>
#include <mathlib.h>

extern particle_t	*active_particles, *free_particles;
extern int	ramp1[8], ramp2[8], ramp3[8];

/*
===============
R_DrawParticles
===============
*/
extern cvar_t  *sv_gravity;
void R_DrawParticles (void)
{
	particle_t		*p, *kill;
	float			grav;
	int				i;
	float			time2, time3;
	float			time1;
	float			dvel;
	float			frametime;
	D_StartParticles ();

	VectorScale (vright, xscaleshrink, r_pright);
	VectorScale (vup, yscaleshrink, r_pup);
	VectorCopy (vpn, r_ppn);

#ifdef QUAKEWORLD
	frametime = host_frametime;
#else
	frametime = cl.time - cl.oldtime;
#endif

	time3 = frametime * 15;
	time2 = frametime * 10; // 15;
	time1 = frametime * 5;
#ifdef QUAKEWORLD
	grav = frametime * 800 * 0.05;
#else
	grav = frametime * sv_gravity->value * 0.05;
#endif
	dvel = 4*frametime;

	for ( ;; )
	{
		kill = active_particles;
		if (kill && kill->die < cl.time)
		{
			active_particles = kill->next;
			kill->next = free_particles;
			free_particles = kill;
			continue;
		}
		break;
	}

	for (p=active_particles ; p ; p=p->next)
	{
		for ( ;; )
		{
			kill = p->next;
			if (kill && kill->die < cl.time)
			{
				p->next = kill->next;
				kill->next = free_particles;
				free_particles = kill;
				continue;
			}
			break;
		}

		D_DrawParticle (p);

		p->org[0] += p->vel[0]*frametime;
		p->org[1] += p->vel[1]*frametime;
		p->org[2] += p->vel[2]*frametime;

		switch (p->type)
		{
		case pt_static:
			break;
		case pt_fire:
			p->ramp += time1;
			if (p->ramp >= 6)
				p->die = -1;
			else
				p->color = ramp3[(int)p->ramp];
			p->vel[2] += grav;
			break;

		case pt_explode:
			p->ramp += time2;
			if (p->ramp >=8)
				p->die = -1;
			else
				p->color = ramp1[(int)p->ramp];
			for (i=0 ; i<3 ; i++)
				p->vel[i] += p->vel[i]*dvel;
			p->vel[2] -= grav;
			break;

		case pt_explode2:
			p->ramp += time3;
			if (p->ramp >=8)
				p->die = -1;
			else
				p->color = ramp2[(int)p->ramp];
			for (i=0 ; i<3 ; i++)
				p->vel[i] -= p->vel[i]*frametime;
			p->vel[2] -= grav;
			break;

		case pt_blob:
			for (i=0 ; i<3 ; i++)
				p->vel[i] += p->vel[i]*dvel;
			p->vel[2] -= grav;
			break;

		case pt_blob2:
			for (i=0 ; i<2 ; i++)
				p->vel[i] -= p->vel[i]*dvel;
			p->vel[2] -= grav;
			break;

		case pt_slowgrav:
		case pt_grav:
			p->vel[2] -= grav;
			break;
		}
	}

	D_EndParticles ();
}