--- /dev/null
+/* -*- Mode: C; tab-width: 4 -*-
+ * forest.c --- draw a fractal forest.
+ */
+#if !defined( lint ) && !defined( SABER )
+static const char sccsid[] = "@(#)forest.c 4.03 97/05/10 xlockmore";
+#endif
+
+/* Copyright (c) 1995 Pascal Pensa <pensa@aurora.unice.fr>
+ *
+ * Original idea : Guillaume Ramey <ramey@aurora.unice.fr>
+ *
+ * Permission to use, copy, modify, and distribute this software and its
+ * documentation for any purpose and without fee is hereby granted,
+ * provided that the above copyright notice appear in all copies and that
+ * both that copyright notice and this permission notice appear in
+ * supporting documentation.
+ *
+ * This file is provided AS IS with no warranties of any kind. The author
+ * shall have no liability with respect to the infringement of copyrights,
+ * trade secrets or any patents by this file or any part thereof. In no
+ * event will the author be liable for any lost revenue or profits or
+ * other special, indirect and consequential damages.
+ *
+ * Revision History:
+ * 10-May-97: Compatible with xscreensaver
+ */
+
+#ifdef STANDALONE
+# define PROGCLASS "Forest"
+# define HACK_INIT init_forest
+# define HACK_DRAW draw_forest
+# define forest_opts xlockmore_opts
+# define DEFAULTS "*count: 100 \n" \
+ "*cycles: 200 \n" \
+ "*delay: 400000 \n" \
+ "*ncolors: 100 \n"
+# define UNIFORM_COLORS
+# include "xlockmore.h" /* from the xscreensaver distribution */
+# include "erase.h"
+#else /* !STANDALONE */
+# include "xlock.h" /* from the xlockmore distribution */
+#endif /* !STANDALONE */
+
+ModeSpecOpt forest_opts = {
+ 0, NULL, 0, NULL, NULL };
+
+
+#define MINTREES 1
+
+#define MINHEIGHT 20 /* Tree height range */
+#define MAXHEIGHT 40
+
+#define MINANGLE 15 /* (degree) angle between soon */
+#define MAXANGLE 35
+#define RANDANGLE 15 /* (degree) Max random angle from default */
+
+#define REDUCE 90 /* Height % from father */
+
+#define ITERLEVEL 10 /* Tree iteration */
+
+#define COLORSPEED 2 /* Color increment */
+
+/* degree to radian */
+#define DEGTORAD(x) (((float)(x)) * M_PI / 180.0)
+
+#define RANGE_RAND(min,max) ((min) + NRAND((max) - (min)))
+
+typedef struct {
+ int width;
+ int height;
+ int time; /* up time */
+ int ntrees;
+} foreststruct;
+
+static foreststruct *forests = NULL;
+
+static void
+draw_tree(ModeInfo * mi,
+ short int x, short int y, short int len,
+ float a, float as, short int c, short int level)
+ /* Father's end */
+ /* Length */
+ /* color */
+ /* Height level */
+ /* Father's angle */
+ /* Father's angle step */
+{
+ Display *display = MI_DISPLAY(mi);
+ Window window = MI_WINDOW(mi);
+ GC gc = MI_GC(mi);
+ short x_1, y_1, x_2, y_2;
+ float a1, a2;
+
+ /* left */
+
+ a1 = a + as + DEGTORAD(NRAND(2 * RANDANGLE) - RANDANGLE);
+
+ x_1 = x + (short) (COSF(a1) * ((float) len));
+ y_1 = y + (short) (SINF(a1) * ((float) len));
+
+ /* right */
+
+ a2 = a - as + DEGTORAD(NRAND(2 * RANDANGLE) - RANDANGLE);
+
+ x_2 = x + (short) (COSF(a2) * ((float) len));
+ y_2 = y + (short) (SINF(a2) * ((float) len));
+
+ if (MI_NPIXELS(mi) > 2) {
+ XSetForeground(display, gc, MI_PIXEL(mi, c));
+ c = (c + COLORSPEED) % MI_NPIXELS(mi);
+ } else
+ XSetForeground(display, gc, MI_WIN_WHITE_PIXEL(mi));
+
+ XDrawLine(display, window, gc, x, y, x_1, y_1);
+ XDrawLine(display, window, gc, x, y, x_2, y_2);
+
+ if (level < 2) {
+ XDrawLine(display, window, gc, x + 1, y, x_1 + 1, y_1);
+ XDrawLine(display, window, gc, x + 1, y, x_2 + 1, y_2);
+ }
+ len = (len * REDUCE * 10) / 1000;
+
+ if (level < ITERLEVEL) {
+ draw_tree(mi, x_1, y_1, len, a1, as, c, level + 1);
+ draw_tree(mi, x_2, y_2, len, a2, as, c, level + 1);
+ }
+}
+
+void
+init_forest(ModeInfo * mi)
+{
+ foreststruct *fp;
+
+ if (forests == NULL) {
+ if ((forests = (foreststruct *) calloc(MI_NUM_SCREENS(mi),
+ sizeof (foreststruct))) == NULL)
+ return;
+ }
+ fp = &forests[MI_SCREEN(mi)];
+
+ fp->width = MI_WIN_WIDTH(mi);
+ fp->height = MI_WIN_HEIGHT(mi);
+ fp->time = 0;
+
+ fp->ntrees = MI_BATCHCOUNT(mi);
+ if (fp->ntrees < -MINTREES)
+ fp->ntrees = NRAND(-fp->ntrees - MINTREES + 1) + MINTREES;
+ else if (fp->ntrees < MINTREES)
+ fp->ntrees = MINTREES;
+ XClearWindow(MI_DISPLAY(mi), MI_WINDOW(mi));
+}
+
+void
+draw_forest(ModeInfo * mi)
+{
+ Display *display = MI_DISPLAY(mi);
+ GC gc = MI_GC(mi);
+ foreststruct *fp = &forests[MI_SCREEN(mi)];
+ short x, y, x_2, y_2, len, c = 0;
+ float a, as;
+
+ if (fp->time < fp->ntrees) {
+
+ x = RANGE_RAND(0, fp->width);
+ y = RANGE_RAND(0, fp->height + MAXHEIGHT);
+ a = -M_PI / 2.0 + DEGTORAD(NRAND(2 * RANDANGLE) - RANDANGLE);
+ as = DEGTORAD(RANGE_RAND(MINANGLE, MAXANGLE));
+ len = ((RANGE_RAND(MINHEIGHT, MAXHEIGHT) * (fp->width / 20)) / 50) + 2;
+
+ if (MI_NPIXELS(mi) > 2) {
+ c = NRAND(MI_NPIXELS(mi));
+ XSetForeground(display, gc, MI_PIXEL(mi, c));
+ c = (c + COLORSPEED) % MI_NPIXELS(mi);
+ } else
+ XSetForeground(display, gc, MI_WIN_WHITE_PIXEL(mi));
+
+ x_2 = x + (short) (COSF(a) * ((float) len));
+ y_2 = y + (short) (SINF(a) * ((float) len));
+
+ XDrawLine(display, MI_WINDOW(mi), gc, x, y, x_2, y_2);
+ XDrawLine(display, MI_WINDOW(mi), gc, x + 1, y, x_2 + 1, y_2);
+
+ draw_tree(mi, x_2, y_2, (len * REDUCE) / 100, a, as, c, 1);
+ }
+ if (++fp->time > MI_CYCLES(mi)) {
+#ifdef STANDALONE
+ erase_full_window(MI_DISPLAY(mi), MI_WINDOW(mi));
+#endif /* STANDALONE */
+ init_forest(mi);
+ }
+}
+
+void
+release_forest(ModeInfo * mi)
+{
+ if (forests != NULL) {
+ (void) free((void *) forests);
+ forests = NULL;
+ }
+}
+
+void
+refresh_forest(ModeInfo * mi)
+{
+ foreststruct *fp = &forests[MI_SCREEN(mi)];
+
+ if (fp->time < fp->ntrees)
+ XClearWindow(MI_DISPLAY(mi), MI_WINDOW(mi));
+ else
+ init_forest(mi);
+}
projects / xscreensaver / blobdiff