rain_saver.c revision 42205 
1/*-
2 * Copyright (c) 1998 Dag-Erling Co�dan Sm�rgrav
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer
10 *    in this position and unchanged.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote products
15 *    derived from this software without specific prior written permission
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 *	$Id$
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
37#include <machine/md_var.h>
38#include <machine/random.h>
39
40#include <saver.h>
41
42static u_char *vid;
43
44#define SCRW 320
45#define SCRH 200
46#define MAX 63
47
48static u_char save_pal[768];
49static u_char rain_pal[768];
50
51static void
52rain_update(void)
53{
54    int i, t;
55
56    t = rain_pal[(MAX*3+2)];
57    for (i = (MAX*3+2); i > 5; i -= 3)
58	rain_pal[i] = rain_pal[i-3];
59    rain_pal[5] = t;
60    load_palette(cur_console, rain_pal);
61}
62
63static void
64rain_saver(int blank)
65{
66    scr_stat *scp = cur_console;
67    static int saved_mode;
68    int i, j, k, pl;
69
70    if (blank) {
71	/* switch to graphics mode */
72	if (scrn_blanked <= 0) {
73	    pl = splhigh();
74	    saved_mode = scp->mode;
75	    scp->mode = M_VGA_CG320;
76	    scp->status |= SAVER_RUNNING|GRAPHICS_MODE;
77	    save_palette(scp, save_pal);
78	    set_mode(scp);
79	    load_palette(scp, rain_pal);
80	    scrn_blanked++;
81	    vid = (u_char *)Crtat;
82	    splx(pl);
83	    bzero(vid, SCRW*SCRH);
84	    for (i = 0; i < SCRW; i += 2)
85		vid[i] = 1 + (random() % MAX);
86	    for (j = 1, k = SCRW; j < SCRH; j++)
87		for (i = 0; i < SCRW; i += 2, k += 2)
88		    vid[k] = (vid[k-SCRW] < MAX) ? 1 + vid[k-SCRW] : 1;
89	}
90
91	/* update display */
92	rain_update();
93
94    } else {
95	/* return to previous video mode */
96	if (scrn_blanked > 0) {
97	    if (saved_mode) {
98		pl = splhigh();
99		scrn_blanked = 0;
100		scp->mode = saved_mode;
101		scp->status &= ~(SAVER_RUNNING|GRAPHICS_MODE);
102		set_mode(scp);
103		load_palette(scp, save_pal);
104		saved_mode = 0;
105		splx(pl);
106	    }
107	}
108    }
109}
110
111static int
112rain_saver_load(void)
113{
114    video_info_t info;
115    int i;
116
117    /* check that the console is capable of running in 320x200x256 */
118    if ((*biosvidsw.get_info)(cur_console->adp, M_VGA_CG320, &info)) {
119        log(LOG_NOTICE, "rain_saver: the console does not support M_VGA_CG320\n");
120	return ENODEV;
121    }
122
123    /* intialize the palette */
124    for (i = 3; i < (MAX+1)*3; i += 3)
125	rain_pal[i+2] = rain_pal[i-1] + 4;
126
127    return add_scrn_saver(rain_saver);
128}
129
130static int
131rain_saver_unload(void)
132{
133    return remove_scrn_saver(rain_saver);
134}
135
136SAVER_MODULE(rain_saver);
137