1/*-
2 * Copyright (c) 2000 Chiharu Shibata
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 * $FreeBSD$
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
47static u_char	*vid;
48static int	blanked;
49
50#ifdef PC98
51#define	VIDEO_MODE	M_PC98_EGC640x400
52#define	VIDEO_MODE_NAME	"M_PC98_EGC640x400"
53#define	SCRW	640
54#define	SCRH	400
55#else
56#define	VIDEO_MODE	M_VGA_CG320
57#define	VIDEO_MODE_NAME	"M_VGA_CG320"
58#define	SCRW	320
59#define	SCRH	200
60#endif
61#define	ORDER	13
62#define	CURVE	3
63#define	OUT	100
64
65static int	cur_x, cur_y;
66static int	curve;
67static u_char	dragon_pal[3*256];	/* zero-filled by the compiler */
68
69static __inline int
70gpset(int x, int y, int val)
71{
72	if (x < 0 || y < 0 || SCRW <= x || SCRH <= y) {
73		return 0;
74	}
75#ifdef PC98
76	vid[(x + y * SCRW) >> 3] = (0x80 >> (x & 7));	/* write new dot */
77#else
78	vid[x + y * SCRW] = val;
79#endif
80	return 1;
81}
82
83static int
84gdraw(int dx, int dy, int val)
85{
86	int	i;
87	int	set = 0;
88
89#ifdef PC98
90	outb(0x7c, 0xcc);	/* GRCG on & RMW mode(disable planeI,G) */
91	outb(0x7e, (val & 1) ? 0xff: 0);	/* tile B */
92	outb(0x7e, (val & 2) ? 0xff: 0);	/* tile R */
93#endif
94	if (dx != 0) {
95		i = cur_x;
96		cur_x += dx;
97		if (dx < 0) {
98			i += dx;
99			dx = -dx;
100		}
101		/* horizontal line */
102		for (; dx >= 0; --dx, ++i) {
103			set |= gpset(i, cur_y, val);
104		}
105	}
106	else {	/* dy != 0 */
107		i = cur_y;
108		cur_y += dy;
109		if (dy < 0) {
110			i += dy;
111			dy = -dy;
112		}
113		/* vertical line */
114		for (; dy >= 0; --dy, ++i) {
115			set |= gpset(cur_x, i, val);
116		}
117	}
118#ifdef PC98
119	outb(0x7c, 0);		/* GRCG off */
120#endif
121	return set;
122}
123
124static void
125dragon_update(video_adapter_t *adp)
126{
127	static int	i, p, q;
128	static int	order, mul, out;
129	static int	org_x, org_y;
130	static int	dx, dy;
131	static unsigned char	fold[1 << (ORDER - 3)];
132#define	GET_FOLD(x)	(fold[(x) >> 3]  &  (1 << ((x) & 7)))
133#define	SET_FOLD(x)	(fold[(x) >> 3] |=  (1 << ((x) & 7)))
134#define	CLR_FOLD(x)	(fold[(x) >> 3] &= ~(1 << ((x) & 7)))
135	int	tmp;
136
137	if (curve > CURVE) {
138		vidd_clear(adp);
139
140		/* set palette of each curves */
141		for (tmp = 0; tmp < 3*CURVE; ++tmp) {
142			dragon_pal[3+tmp] = (u_char)random();
143		}
144		vidd_load_palette(adp, dragon_pal);
145
146		mul = ((random() & 7) + 1) * (SCRW / 320);
147		org_x = random() % SCRW; org_y = random() % SCRH;
148
149		curve = 0;
150		order = ORDER;
151	}
152
153	if (order >= ORDER) {
154		++curve;
155
156		cur_x = org_x; cur_y = org_y;
157
158		switch (curve) {
159		case 1:
160			dx = 0; dy = mul;
161			break;
162		case 2:
163			dx = mul; dy = 0;
164			break;
165		case 3:
166			dx = 0; dy = -mul;
167			break;
168		}
169		(void)gdraw(dx, dy, curve); out = 0;
170
171		order = 0;
172		q = p = 0; i = q + 1;
173	}
174
175	if (i > q) {
176		SET_FOLD(p); q = p * 2;
177
178		++order;
179		i = p; p = q + 1;
180	}
181
182	if (GET_FOLD(q-i) != 0) {
183		CLR_FOLD(i);
184		tmp = dx; dx =  dy; dy = -tmp;	/* turn right */
185	}
186	else {
187		SET_FOLD(i);
188		tmp = dx; dx = -dy; dy =  tmp;	/* turn left */
189	}
190	if (gdraw(dx, dy, curve)) {
191		out = 0;
192	}
193	else {
194		if (++out > OUT) {
195			order = ORDER;	/* force to terminate this curve */
196		}
197	}
198	++i;
199}
200
201static int
202dragon_saver(video_adapter_t *adp, int blank)
203{
204	int pl;
205
206	if (blank) {
207		/* switch to graphics mode */
208		if (blanked <= 0) {
209			pl = splhigh();
210			vidd_set_mode(adp, VIDEO_MODE);
211			vid = (u_char *)adp->va_window;
212			curve = CURVE + 1;
213			++blanked;
214			splx(pl);
215		}
216
217		/* update display */
218		dragon_update(adp);
219	}
220	else {
221		blanked = 0;
222	}
223	return 0;
224}
225
226static int
227dragon_init(video_adapter_t *adp)
228{
229	video_info_t info;
230
231	/* check that the console is capable of running in 320x200x256 */
232	if (vidd_get_info(adp, VIDEO_MODE, &info)) {
233		log(LOG_NOTICE,
234		    "%s: the console does not support " VIDEO_MODE_NAME "\n",
235		    SAVER_NAME);
236		return ENODEV;
237	}
238
239	blanked = 0;
240	return 0;
241}
242
243static int
244dragon_term(video_adapter_t *adp)
245{
246	return 0;
247}
248
249static scrn_saver_t dragon_module = {
250	SAVER_NAME,
251	dragon_init,
252	dragon_term,
253	dragon_saver,
254	NULL,
255};
256
257SAVER_MODULE(dragon_saver, dragon_module);
258