1 /* -*- Mode: C; tab-width: 4 -*- */
2 /* vines --- vine fractals */
3
4 #if 0
5 static const char sccsid[] = "@(#)vines.c 5.00 2000/11/01 xlockmore";
6 #endif
7
8 /*-
9 * Copyright (c) 1997 by Tracy Camp campt@hurrah.com
10 *
11 * Permission to use, copy, modify, and distribute this software and its
12 * documentation for any purpose and without fee is hereby granted,
13 * provided that the above copyright notice appear in all copies and that
14 * both that copyright notice and this permission notice appear in
15 * supporting documentation.
16 *
17 * This file is provided AS IS with no warranties of any kind. The author
18 * shall have no liability with respect to the infringement of copyrights,
19 * trade secrets or any patents by this file or any part thereof. In no
20 * event will the author be liable for any lost revenue or profits or
21 * other special, indirect and consequential damages.
22 *
23 * If you make a modification I would of course appreciate a copy.
24 *
25 * Revision History:
26 * 01-Nov-2000: Allocation checks
27 * 11-Jul-1997: David Hansen <dhansen@metapath.com>
28 * Changed names to vines and modified draw loop
29 * to honor batchcount so vines can be grown or plotted.
30 * 10-May-1997: Compatible with xscreensaver
31 * 21-Mar-1997: David Hansen <dhansen@metapath.com>
32 * Updated mode to draw complete patterns on every
33 * iteration instead of growing the vine. Also made
34 * adjustments to randomization and changed variable
35 * names to make logic easier to follow.
36 */
37
38 /*-
39 * This was modifed from a 'screen saver' that a friend and I
40 * wrote on our TI-8x calculators in high school physics one day
41 * Basically another geometric pattern generator, this ones claim
42 * to fame is a pseudo-fractal looking vine like pattern that creates
43 * nifty whorls and loops.
44 */
45
46 #ifdef STANDALONE
47 # define MODE_vines
48 # define DEFAULTS "*delay: 200000 \n" \
49 "*count: 0 \n" \
50 "*ncolors: 64 \n" \
51 "*fpsSolid: true \n" \
52 "*lowrez: True \n" \
53
54 # include "xlockmore.h" /* in xscreensaver distribution */
55 # define free_vines 0
56 # define release_vines 0
57 # define reshape_vines 0
58 # define vines_handle_event 0
59 #else /* STANDALONE */
60 # include "xlock.h" /* in xlockmore distribution */
61 #endif /* STANDALONE */
62
63 #ifdef MODE_vines
64
65 ENTRYPOINT ModeSpecOpt vines_opts =
66 {0, (XrmOptionDescRec *) NULL, 0, (argtype *) NULL, (OptionStruct *) NULL};
67
68 #ifdef USE_MODULES
69 ModStruct vines_description =
70 {"vines", "init_vines", "draw_vines", (char *) NULL,
71 "refresh_vines", "init_vines", (char *) NULL, &vines_opts,
72 200000, 0, 1, 1, 64, 1.0, "",
73 "Shows fractals", 0, NULL};
74
75 #endif
76
77 typedef struct {
78 int a;
79 int x1;
80 int y1;
81 int x2;
82 int y2;
83 int i;
84 int length;
85 int iterations;
86 int constant;
87 int ang;
88 int centerx;
89 int centery;
90 } vinestruct;
91
92 static vinestruct *vines = (vinestruct *) NULL;
93
94 #ifndef STANDALONE
95 ENTRYPOINT void
refresh_vines(ModeInfo * mi)96 refresh_vines(ModeInfo * mi)
97 {
98 MI_CLEARWINDOW(mi);
99 } /* refresh_vines */
100 #endif
101
102 ENTRYPOINT void
init_vines(ModeInfo * mi)103 init_vines(ModeInfo * mi)
104 {
105 vinestruct *fp;
106
107 MI_INIT (mi, vines);
108 fp = &vines[MI_SCREEN(mi)];
109
110 fp->i = 0;
111 fp->length = 0;
112 fp->iterations = 30 + NRAND(100);
113
114 MI_CLEARWINDOW(mi);
115 } /* init_vines */
116
117 ENTRYPOINT void
draw_vines(ModeInfo * mi)118 draw_vines(ModeInfo * mi)
119 {
120 Display *display = MI_DISPLAY(mi);
121 GC gc = MI_GC(mi);
122 int count;
123 vinestruct *fp;
124
125 if (vines == NULL)
126 return;
127 fp = &vines[MI_SCREEN(mi)];
128
129 MI_IS_DRAWN(mi) = True;
130 if (fp->i >= fp->length) {
131 if (--(fp->iterations) == 0) {
132 init_vines(mi);
133 return;
134 }
135 fp->centerx = NRAND(MI_WIDTH(mi));
136 fp->centery = NRAND(MI_HEIGHT(mi));
137
138 fp->ang = 60 + NRAND(720);
139 fp->length = 100 + NRAND(3000);
140 fp->constant = fp->length * (10 + NRAND(10));
141
142 fp->i = 0;
143 fp->a = 0;
144 fp->x1 = 0;
145 fp->y1 = 0;
146 fp->x2 = 1;
147 fp->y2 = 0;
148
149 if (MI_NPIXELS(mi) > 2)
150 XSetForeground(display, gc, MI_PIXEL(mi, NRAND(MI_NPIXELS(mi))));
151 else
152 XSetForeground(display, gc, MI_WHITE_PIXEL(mi));
153 }
154 count = fp->i + MI_COUNT(mi);
155 if ((count <= fp->i) || (count > fp->length))
156 count = fp->length;
157
158 while (fp->i < count) {
159 XDrawLine(display, MI_WINDOW(mi), gc,
160 fp->centerx + (fp->x1 / fp->constant),
161 fp->centery - (fp->y1 / fp->constant),
162 fp->centerx + (fp->x2 / fp->constant),
163 fp->centery - (fp->y2 / fp->constant));
164
165 fp->a += (fp->ang * fp->i);
166
167 fp->x1 = fp->x2;
168 fp->y1 = fp->y2;
169
170 fp->x2 += (int) (fp->i * (cos((double) fp->a) * 360.0) / (2.0 * M_PI));
171 fp->y2 += (int) (fp->i * (sin((double) fp->a) * 360.0) / (2.0 * M_PI));
172 fp->i++;
173 }
174 } /* draw_vines */
175
176
177 XSCREENSAVER_MODULE ("Vines", vines)
178
179 #endif /* MODE_vines */
180