1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 2000 Chiharu Shibata
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer
12 * in this position and unchanged.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. The name of the author may not be used to endorse or promote products
17 * derived from this software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/kernel.h>
34 #include <sys/module.h>
35 #include <sys/syslog.h>
36 #include <sys/consio.h>
37 #include <sys/fbio.h>
38
39 #include <sys/random.h>
40
41 #include <dev/fb/fbreg.h>
42 #include <dev/fb/splashreg.h>
43 #include <dev/syscons/syscons.h>
44
45 #define SAVER_NAME "dragon_saver"
46
47 static u_char *vid;
48 static int blanked;
49
50 #define VIDEO_MODE M_VGA_CG320
51 #define VIDEO_MODE_NAME "M_VGA_CG320"
52 #define SCRW 320
53 #define SCRH 200
54 #define ORDER 13
55 #define CURVE 3
56 #define OUT 100
57
58 static int cur_x, cur_y;
59 static int curve;
60 static u_char dragon_pal[3*256]; /* zero-filled by the compiler */
61
62 static __inline int
gpset(int x,int y,int val)63 gpset(int x, int y, int val)
64 {
65 if (x < 0 || y < 0 || SCRW <= x || SCRH <= y) {
66 return 0;
67 }
68 vid[x + y * SCRW] = val;
69 return 1;
70 }
71
72 static int
gdraw(int dx,int dy,int val)73 gdraw(int dx, int dy, int val)
74 {
75 int i;
76 int set = 0;
77
78 if (dx != 0) {
79 i = cur_x;
80 cur_x += dx;
81 if (dx < 0) {
82 i += dx;
83 dx = -dx;
84 }
85 /* horizontal line */
86 for (; dx >= 0; --dx, ++i) {
87 set |= gpset(i, cur_y, val);
88 }
89 }
90 else { /* dy != 0 */
91 i = cur_y;
92 cur_y += dy;
93 if (dy < 0) {
94 i += dy;
95 dy = -dy;
96 }
97 /* vertical line */
98 for (; dy >= 0; --dy, ++i) {
99 set |= gpset(cur_x, i, val);
100 }
101 }
102 return set;
103 }
104
105 static void
dragon_update(video_adapter_t * adp)106 dragon_update(video_adapter_t *adp)
107 {
108 static int i, p, q;
109 static int order, mul, out;
110 static int org_x, org_y;
111 static int dx, dy;
112 static unsigned char fold[1 << (ORDER - 3)];
113 #define GET_FOLD(x) (fold[(x) >> 3] & (1 << ((x) & 7)))
114 #define SET_FOLD(x) (fold[(x) >> 3] |= (1 << ((x) & 7)))
115 #define CLR_FOLD(x) (fold[(x) >> 3] &= ~(1 << ((x) & 7)))
116 int tmp;
117
118 if (curve > CURVE) {
119 vidd_clear(adp);
120
121 /* set palette of each curves */
122 for (tmp = 0; tmp < 3*CURVE; ++tmp) {
123 dragon_pal[3+tmp] = (u_char)random();
124 }
125 vidd_load_palette(adp, dragon_pal);
126
127 mul = ((random() & 7) + 1) * (SCRW / 320);
128 org_x = random() % SCRW; org_y = random() % SCRH;
129
130 curve = 0;
131 order = ORDER;
132 }
133
134 if (order >= ORDER) {
135 ++curve;
136
137 cur_x = org_x; cur_y = org_y;
138
139 switch (curve) {
140 case 1:
141 dx = 0; dy = mul;
142 break;
143 case 2:
144 dx = mul; dy = 0;
145 break;
146 case 3:
147 dx = 0; dy = -mul;
148 break;
149 }
150 (void)gdraw(dx, dy, curve); out = 0;
151
152 order = 0;
153 q = p = 0; i = q + 1;
154 }
155
156 if (i > q) {
157 SET_FOLD(p); q = p * 2;
158
159 ++order;
160 i = p; p = q + 1;
161 }
162
163 if (GET_FOLD(q-i) != 0) {
164 CLR_FOLD(i);
165 tmp = dx; dx = dy; dy = -tmp; /* turn right */
166 }
167 else {
168 SET_FOLD(i);
169 tmp = dx; dx = -dy; dy = tmp; /* turn left */
170 }
171 if (gdraw(dx, dy, curve)) {
172 out = 0;
173 }
174 else {
175 if (++out > OUT) {
176 order = ORDER; /* force to terminate this curve */
177 }
178 }
179 ++i;
180 }
181
182 static int
dragon_saver(video_adapter_t * adp,int blank)183 dragon_saver(video_adapter_t *adp, int blank)
184 {
185 int pl;
186
187 if (blank) {
188 /* switch to graphics mode */
189 if (blanked <= 0) {
190 pl = splhigh();
191 vidd_set_mode(adp, VIDEO_MODE);
192 vid = (u_char *)adp->va_window;
193 curve = CURVE + 1;
194 ++blanked;
195 splx(pl);
196 }
197
198 /* update display */
199 dragon_update(adp);
200 }
201 else {
202 blanked = 0;
203 }
204 return 0;
205 }
206
207 static int
dragon_init(video_adapter_t * adp)208 dragon_init(video_adapter_t *adp)
209 {
210 video_info_t info;
211
212 /* check that the console is capable of running in 320x200x256 */
213 if (vidd_get_info(adp, VIDEO_MODE, &info)) {
214 log(LOG_NOTICE,
215 "%s: the console does not support " VIDEO_MODE_NAME "\n",
216 SAVER_NAME);
217 return ENODEV;
218 }
219
220 blanked = 0;
221 return 0;
222 }
223
224 static int
dragon_term(video_adapter_t * adp)225 dragon_term(video_adapter_t *adp)
226 {
227 return 0;
228 }
229
230 static scrn_saver_t dragon_module = {
231 SAVER_NAME,
232 dragon_init,
233 dragon_term,
234 dragon_saver,
235 NULL,
236 };
237
238 SAVER_MODULE(dragon_saver, dragon_module);
239