1 /*
2 Copyright (C) 1996-1997 Id Software, Inc.
3
4 This program is free software; you can redistribute it and/or
5 modify it under the terms of the GNU General Public License
6 as published by the Free Software Foundation; either version 2
7 of the License, or (at your option) any later version.
8
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
12
13 See the GNU General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
18
19 */
20 // r_sky.c
21
22 #include "quakedef.h"
23 #include "r_local.h"
24 #include "d_local.h"
25
26
27 int iskyspeed = 8;
28 int iskyspeed2 = 2;
29 float skyspeed, skyspeed2;
30
31 float skytime;
32
33 byte *r_skysource;
34
35 int r_skymade;
36 int r_skydirect; // not used?
37
38
39 // TODO: clean up these routines
40
41 byte bottomsky[128*131];
42 byte bottommask[128*131];
43 byte newsky[128*256]; // newsky and topsky both pack in here, 128 bytes
44 // of newsky on the left of each scan, 128 bytes
45 // of topsky on the right, because the low-level
46 // drawers need 256-byte scan widths
47
48
49 /*
50 =============
51 R_InitSky
52
53 A sky texture is 256*128, with the right side being a masked overlay
54 ==============
55 */
R_InitSky(texture_t * mt)56 void R_InitSky (texture_t *mt)
57 {
58 int i, j;
59 byte *src;
60
61 src = (byte *)mt + mt->offsets[0];
62
63 for (i=0 ; i<128 ; i++)
64 {
65 for (j=0 ; j<128 ; j++)
66 {
67 newsky[(i*256) + j + 128] = src[i*256 + j + 128];
68 }
69 }
70
71 for (i=0 ; i<128 ; i++)
72 {
73 for (j=0 ; j<131 ; j++)
74 {
75 if (src[i*256 + (j & 0x7F)])
76 {
77 bottomsky[(i*131) + j] = src[i*256 + (j & 0x7F)];
78 bottommask[(i*131) + j] = 0;
79 }
80 else
81 {
82 bottomsky[(i*131) + j] = 0;
83 bottommask[(i*131) + j] = 0xff;
84 }
85 }
86 }
87
88 r_skysource = newsky;
89 }
90
91
92 /*
93 =================
94 R_MakeSky
95 =================
96 */
R_MakeSky(void)97 void R_MakeSky (void)
98 {
99 int x, y;
100 int ofs, baseofs;
101 int xshift, yshift;
102 unsigned *pnewsky;
103 static int xlast = -1, ylast = -1;
104
105 xshift = skytime*skyspeed;
106 yshift = skytime*skyspeed;
107
108 if ((xshift == xlast) && (yshift == ylast))
109 return;
110
111 xlast = xshift;
112 ylast = yshift;
113
114 pnewsky = (unsigned *)&newsky[0];
115
116 for (y=0 ; y<SKYSIZE ; y++)
117 {
118 baseofs = ((y+yshift) & SKYMASK) * 131;
119
120 // FIXME: clean this up
121 #if UNALIGNED_OK
122
123 for (x=0 ; x<SKYSIZE ; x += 4)
124 {
125 ofs = baseofs + ((x+xshift) & SKYMASK);
126
127 // PORT: unaligned dword access to bottommask and bottomsky
128
129 *pnewsky = (*(pnewsky + (128 / sizeof (unsigned))) &
130 *(unsigned *)&bottommask[ofs]) |
131 *(unsigned *)&bottomsky[ofs];
132 pnewsky++;
133 }
134
135 #else
136
137 for (x=0 ; x<SKYSIZE ; x++)
138 {
139 ofs = baseofs + ((x+xshift) & SKYMASK);
140
141 *(byte *)pnewsky = (*((byte *)pnewsky + 128) &
142 *(byte *)&bottommask[ofs]) |
143 *(byte *)&bottomsky[ofs];
144 pnewsky = (unsigned *)((byte *)pnewsky + 1);
145 }
146
147 #endif
148
149 pnewsky += 128 / sizeof (unsigned);
150 }
151
152 r_skymade = 1;
153 }
154
155
156 /*
157 =================
158 R_GenSkyTile
159 =================
160 */
R_GenSkyTile(void * pdest)161 void R_GenSkyTile (void *pdest)
162 {
163 int x, y;
164 int ofs, baseofs;
165 int xshift, yshift;
166 unsigned *pnewsky;
167 unsigned *pd;
168
169 xshift = skytime*skyspeed;
170 yshift = skytime*skyspeed;
171
172 pnewsky = (unsigned *)&newsky[0];
173 pd = (unsigned *)pdest;
174
175 for (y=0 ; y<SKYSIZE ; y++)
176 {
177 baseofs = ((y+yshift) & SKYMASK) * 131;
178
179 // FIXME: clean this up
180 #if UNALIGNED_OK
181
182 for (x=0 ; x<SKYSIZE ; x += 4)
183 {
184 ofs = baseofs + ((x+xshift) & SKYMASK);
185
186 // PORT: unaligned dword access to bottommask and bottomsky
187
188 *pd = (*(pnewsky + (128 / sizeof (unsigned))) &
189 *(unsigned *)&bottommask[ofs]) |
190 *(unsigned *)&bottomsky[ofs];
191 pnewsky++;
192 pd++;
193 }
194
195 #else
196
197 for (x=0 ; x<SKYSIZE ; x++)
198 {
199 ofs = baseofs + ((x+xshift) & SKYMASK);
200
201 *(byte *)pd = (*((byte *)pnewsky + 128) &
202 *(byte *)&bottommask[ofs]) |
203 *(byte *)&bottomsky[ofs];
204 pnewsky = (unsigned *)((byte *)pnewsky + 1);
205 pd = (unsigned *)((byte *)pd + 1);
206 }
207
208 #endif
209
210 pnewsky += 128 / sizeof (unsigned);
211 }
212 }
213
214
215 /*
216 =================
217 R_GenSkyTile16
218 =================
219 */
R_GenSkyTile16(void * pdest)220 void R_GenSkyTile16 (void *pdest)
221 {
222 int x, y;
223 int ofs, baseofs;
224 int xshift, yshift;
225 byte *pnewsky;
226 unsigned short *pd;
227
228 xshift = skytime * skyspeed;
229 yshift = skytime * skyspeed;
230
231 pnewsky = (byte *)&newsky[0];
232 pd = (unsigned short *)pdest;
233
234 for (y=0 ; y<SKYSIZE ; y++)
235 {
236 baseofs = ((y+yshift) & SKYMASK) * 131;
237
238 // FIXME: clean this up
239 // FIXME: do faster unaligned version?
240 for (x=0 ; x<SKYSIZE ; x++)
241 {
242 ofs = baseofs + ((x+xshift) & SKYMASK);
243
244 *pd = d_8to16table[(*(pnewsky + 128) &
245 *(byte *)&bottommask[ofs]) |
246 *(byte *)&bottomsky[ofs]];
247 pnewsky++;
248 pd++;
249 }
250
251 pnewsky += TILE_SIZE;
252 }
253 }
254
255
256 /*
257 =============
258 R_SetSkyFrame
259 ==============
260 */
R_SetSkyFrame(void)261 void R_SetSkyFrame (void)
262 {
263 int g, s1, s2;
264 float temp;
265
266 skyspeed = iskyspeed;
267 skyspeed2 = iskyspeed2;
268
269 g = GreatestCommonDivisor (iskyspeed, iskyspeed2);
270 s1 = iskyspeed / g;
271 s2 = iskyspeed2 / g;
272 temp = SKYSIZE * s1 * s2;
273
274 skytime = cl.time - ((int)(cl.time / temp) * temp);
275
276
277 r_skymade = 0;
278 }
279
280
281