1 /* forest.c (aka xtree.c), Copyright (c) 1999
2 * Peter Baumung <unn6@rz.uni-karlsruhe.de>
5 * xscreensaver, Copyright (c) 1992, 1995, 1997
6 * Jamie Zawinski <jwz@netscape.com>
8 * Permission to use, copy, modify, distribute, and sell this software and its
9 * documentation for any purpose is hereby granted without fee, provided that
10 * the above copyright notice appear in all copies and that both that
11 * copyright notice and this permission notice appear in supporting
12 * documentation. No representations are made about the suitability of this
13 * software for any purpose. It is provided "as is" without express or
20 # define PROGCLASS "Forest" /*"XTree"*/
21 # define HACK_INIT init_trees
22 # define HACK_DRAW draw_trees
23 # define trees_opts xlockmore_opts
24 # define DEFAULTS "*delay: 500000 \n" \
26 "*eraseSpeed: 400 \n" \
28 "*installColormap False"
29 # include "xlockmore.h" /* from the xscreensaver distribution */
30 #else /* !STANDALONE */
31 # include "xlock.h" /* from the xlockmore distribution */
32 #endif /* !STANDALONE */
34 ModeSpecOpt trees_opts = {0, NULL, 0, NULL, NULL};
46 static treestruct *trees = NULL;
51 static long colorM[12] = {0xff0000, 0xff8000, 0xffff00, 0x80ff00,
52 0x00ff00, 0x00ff80, 0x00ffff, 0x0080ff,
53 0x0000ff, 0x8000ff, 0xff00ff, 0xff0080};
55 static long colorV[12] = {0x0a0000, 0x0a0500, 0x0a0a00, 0x050a00,
56 0x000a00, 0x000a05, 0x000a0a, 0x00050a,
57 0x00000a, 0x05000a, 0x0a000a, 0x0a0005};
59 void init_trees(ModeInfo * mi) {
60 unsigned long pixels[20];
62 Display *display = MI_DISPLAY(mi);
67 trees = (treestruct *) calloc(MI_NUM_SCREENS(mi), sizeof (treestruct));
72 if (mi->npixels > 20) {
73 printf("%d colors selected. Setting limit to 20...\n", mi->npixels);
77 if (mi->npixels < 4) {
78 for (i = 0; i < mi->npixels; i++) {
79 colors[i].red = 65535 * (i & 1);
80 colors[i].green = 65535 * (i & 1);
81 colors[i].blue = 65535 * (i & 1);
82 colors[i].flags = DoRed | DoGreen | DoBlue;
85 if (mi->npixels < 8) {
86 for (i = 0; i < mi->npixels; i++) {
87 colors[i].red = 32768 + 4096 * (i % 4);
88 colors[i].green = 32768 + 4096 * (i % 4);
89 colors[i].blue = 32768 + 4096 * (i % 4);
90 colors[i].flags = DoRed | DoGreen | DoBlue;
93 for (i = 0; i < mi->npixels; i++) {
94 colors[i].red = 24576 + 4096 * (i % 4);
95 colors[i].green = 10240 + 2048 * (i % 4);
97 colors[i].flags = DoRed | DoGreen | DoBlue;
102 for (i = 0; i < mi->npixels; i++)
103 if (!XAllocColor(display, mi->xgwa.colormap, &colors[i])) break;
106 XSetForeground(display, gc, colors[1].pixel);
109 XClearWindow(display, MI_WINDOW(mi));
110 XSetLineAttributes(display, gc, 2, LineSolid, CapButt, JoinMiter);
111 tree = &trees[MI_SCREEN(mi)];
113 tree->season = NRAND(12);
115 for (i = 4; i < mi->npixels; i++) {
116 int sIndex = (tree->season + (i-4) / 4) % 12;
117 long color = colorM[sIndex] - 2 * colorV[sIndex] * (i % 4);
118 colors[i].red = (color & 0xff0000) / 256;
119 colors[i].green = (color & 0x00ff00);
120 colors[i].blue = (color & 0x0000ff) * 256;
121 colors[i].flags = DoRed | DoGreen | DoBlue;
124 for (i = 0; i < color; i++)
125 pixels[i] = colors[i].pixel;
127 XFreeColors(display, mi->xgwa.colormap, pixels, mi->npixels, 0L);
129 for (i = 0; i < mi->npixels; i++)
130 if (!XAllocColor(display, mi->xgwa.colormap, &colors[i])) break;
135 double rRand(double a, double b) {
136 return (a+(b-a)*NRAND(10001)/10000.0);
139 void draw_line(ModeInfo * mi,
140 int x1, int y1, int x2, int y2,
141 double angle, int widths, int widthe) {
143 Display *display = MI_DISPLAY(mi);
145 double sns = 0.5*widths*sin(angle + M_PI_2);
146 double css = 0.5*widths*cos(angle + M_PI_2);
147 double sne = 0.5*widthe*sin(angle + M_PI_2);
148 double cse = 0.5*widthe*cos(angle + M_PI_2);
150 int xs1 = (int) (x1-sns);
151 int xs2 = (int) (x1+sns);
152 int ys1 = (int) (y1-css);
153 int ys2 = (int) (y1+css);
154 int xe1 = (int) (x2-sne);
155 int xe2 = (int) (x2+sne);
156 int ye1 = (int) (y2-cse);
157 int ye2 = (int) (y2+cse);
160 for (i = 0; i < widths; i++) {
162 XSetForeground(display, gc, colors[i*4/widths].pixel);
163 XDrawLine(display, MI_WINDOW(mi), gc,
164 xs1+(xs2-xs1)*i/widths, ys1+(ys2-ys1)*i/widths,
165 xe1+(xe2-xe1)*i/widths, ye1+(ye2-ye1)*i/widths);
169 void draw_tree_rec(ModeInfo * mi, double thick, int x, int y, double angle) {
170 treestruct *tree = &trees[MI_SCREEN(mi)];
171 Display *display = MI_DISPLAY(mi);
173 int length = (24+NRAND(12))*tree->size;
174 int a = (int) (x - length*sin(angle));
175 int b = (int) (y - length*cos(angle));
178 draw_line(mi, x, y, a, b, angle, thick*tree->size, 0.68*thick*tree->size);
181 draw_tree_rec(mi, 0.68*thick, a, b, 0.8*angle+rRand(-0.2, 0.2));
182 if (thick < tree->thick-1) {
183 draw_tree_rec(mi, 0.68*thick, a, b, angle+rRand(0.2, 0.9));
184 draw_tree_rec(mi, 0.68*thick, (a+x)/2, (b+y)/2, angle-rRand(0.2, 0.9));
188 if (thick < 0.5*tree->thick) {
189 int nleaf = 12 + NRAND(4);
191 for (i = 0; i < nleaf; i++) {
192 leaf[i].x = a + (int) (tree->size * rRand(-12, 12));
193 leaf[i].y = b + (int) (tree->size * rRand(-12, 12));
194 leaf[i].width = (int) (tree->size * rRand(2, 6));
195 leaf[i].height = leaf[i].width;
197 leaf[i].angle2 = 360 * 64;
199 if (mi->npixels >= 4)
200 XSetForeground(display, gc, colors[tree->color+NRAND(4)].pixel);
201 XFillArcs(display, MI_WINDOW(mi), gc, leaf, nleaf);
205 void draw_trees(ModeInfo * mi) {
206 treestruct *tree = &trees[MI_SCREEN(mi)];
207 int width = MI_WIN_WIDTH(mi);
208 int height = MI_WIN_HEIGHT(mi);
210 if (--(tree->toDo) == 0) {
215 tree->x = NRAND(width);
216 tree->y = (int) (1.25 * height * (1 - tree->toDo / 23.0));
217 tree->thick = rRand(7, 12);
218 tree->size = height / 480.0;
222 tree->color = 4 * (1 + NRAND(color / 4 - 1));
225 draw_tree_rec(mi, tree->thick, tree->x, tree->y, rRand(-0.1, 0.1));
228 void release_trees(ModeInfo * mi) {
230 (void) free((void *) trees);