1/*
2Copyright (C) 1996-1997 Id Software, Inc.
3
4This program is free software; you can redistribute it and/or
5modify it under the terms of the GNU General Public License
6as published by the Free Software Foundation; either version 2
7of the License, or (at your option) any later version.
8
9This program is distributed in the hope that it will be useful,
10but WITHOUT ANY WARRANTY; without even the implied warranty of
11MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
12
13See the GNU General Public License for more details.
14
15You should have received a copy of the GNU General Public License
16along with this program; if not, write to the Free Software
17Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
18
19*/
20// d_part.c: software driver module for drawing particles
21
22#include "quakedef.h"
23#include "d_local.h"
24
25
26/*
27==============
28D_EndParticles
29==============
30*/
31void D_EndParticles (void)
32{
33// not used by software driver
34}
35
36
37/*
38==============
39D_StartParticles
40==============
41*/
42void D_StartParticles (void)
43{
44// not used by software driver
45}
46
47
48#if	!id386
49
50/*
51==============
52D_DrawParticle
53==============
54*/
55void D_DrawParticle (particle_t *pparticle)
56{
57	vec3_t	local, transformed;
58	float	zi;
59	byte	*pdest;
60	short	*pz;
61	int		i, izi, pix, count, u, v;
62
63// transform point
64	VectorSubtract (pparticle->org, r_origin, local);
65
66	transformed[0] = DotProduct(local, r_pright);
67	transformed[1] = DotProduct(local, r_pup);
68	transformed[2] = DotProduct(local, r_ppn);
69
70	if (transformed[2] < PARTICLE_Z_CLIP)
71		return;
72
73// project the point
74// FIXME: preadjust xcenter and ycenter
75	zi = 1.0 / transformed[2];
76	u = (int)(xcenter + zi * transformed[0] + 0.5);
77	v = (int)(ycenter - zi * transformed[1] + 0.5);
78
79	if ((v > d_vrectbottom_particle) ||
80		(u > d_vrectright_particle) ||
81		(v < d_vrecty) ||
82		(u < d_vrectx))
83	{
84		return;
85	}
86
87	pz = d_pzbuffer + (d_zwidth * v) + u;
88	pdest = d_viewbuffer + d_scantable[v] + u;
89	izi = (int)(zi * 0x8000);
90
91	pix = izi >> d_pix_shift;
92
93	if (pix < d_pix_min)
94		pix = d_pix_min;
95	else if (pix > d_pix_max)
96		pix = d_pix_max;
97
98	switch (pix)
99	{
100	case 1:
101		count = 1 << d_y_aspect_shift;
102
103		for ( ; count ; count--, pz += d_zwidth, pdest += screenwidth)
104		{
105			if (pz[0] <= izi)
106			{
107				pz[0] = izi;
108				pdest[0] = pparticle->color;
109			}
110		}
111		break;
112
113	case 2:
114		count = 2 << d_y_aspect_shift;
115
116		for ( ; count ; count--, pz += d_zwidth, pdest += screenwidth)
117		{
118			if (pz[0] <= izi)
119			{
120				pz[0] = izi;
121				pdest[0] = pparticle->color;
122			}
123
124			if (pz[1] <= izi)
125			{
126				pz[1] = izi;
127				pdest[1] = pparticle->color;
128			}
129		}
130		break;
131
132	case 3:
133		count = 3 << d_y_aspect_shift;
134
135		for ( ; count ; count--, pz += d_zwidth, pdest += screenwidth)
136		{
137			if (pz[0] <= izi)
138			{
139				pz[0] = izi;
140				pdest[0] = pparticle->color;
141			}
142
143			if (pz[1] <= izi)
144			{
145				pz[1] = izi;
146				pdest[1] = pparticle->color;
147			}
148
149			if (pz[2] <= izi)
150			{
151				pz[2] = izi;
152				pdest[2] = pparticle->color;
153			}
154		}
155		break;
156
157	case 4:
158		count = 4 << d_y_aspect_shift;
159
160		for ( ; count ; count--, pz += d_zwidth, pdest += screenwidth)
161		{
162			if (pz[0] <= izi)
163			{
164				pz[0] = izi;
165				pdest[0] = pparticle->color;
166			}
167
168			if (pz[1] <= izi)
169			{
170				pz[1] = izi;
171				pdest[1] = pparticle->color;
172			}
173
174			if (pz[2] <= izi)
175			{
176				pz[2] = izi;
177				pdest[2] = pparticle->color;
178			}
179
180			if (pz[3] <= izi)
181			{
182				pz[3] = izi;
183				pdest[3] = pparticle->color;
184			}
185		}
186		break;
187
188	default:
189		count = pix << d_y_aspect_shift;
190
191		for ( ; count ; count--, pz += d_zwidth, pdest += screenwidth)
192		{
193			for (i=0 ; i<pix ; i++)
194			{
195				if (pz[i] <= izi)
196				{
197					pz[i] = izi;
198					pdest[i] = pparticle->color;
199				}
200			}
201		}
202		break;
203	}
204}
205
206#endif	// !id386
207
208