From http://www.jwz.org/xscreensaver/xscreensaver-5.37.tar.gz
[xscreensaver] / hacks / discrete.c
index 7f336a65d2e47044ea73794d53d9d010f728aa60..ecf4ce5c959f5a8816141410d7d6e3f3f52ac78c 100644 (file)
@@ -1,13 +1,12 @@
 /* -*- Mode: C; tab-width: 4 -*- */
 /* discrete --- chaotic mappings */
 
-#if !defined( lint ) && !defined( SABER )
-static const char sccsid[] = "@(#)discrete.c 4.10 98/04/24 xlockmore";
-
+#if 0
+static const char sccsid[] = "@(#)discrete.c   5.00 2000/11/01 xlockmore";
 #endif
 
 /*-
- * Copyright (c) 1996 by Tim Auckland <Tim.Auckland@Sun.COM>
+ * Copyright (c) 1996 by Tim Auckland <tda10.geo@yahoo.com>
  *
  * Permission to use, copy, modify, and distribute this software and its
  * documentation for any purpose and without fee is hereby granted,
@@ -27,36 +26,37 @@ static const char sccsid[] = "@(#)discrete.c 4.10 98/04/24 xlockmore";
  * Map" and the "Bird in a Thornbush" fractal.
  *
  * Revision History:
- * 31-Jul-97: Ported to xlockmore-4
- * 08-Aug-96: Adapted from hop.c Copyright (c) 1991 by Patrick J. Naughton.
+ * 01-Nov-2000: Allocation checks
+ * 31-Jul-1997: Ported to xlockmore-4
+ * 08-Aug-1996: Adapted from hop.c Copyright (c) 1991 by Patrick J. Naughton.
  */
 
 #ifdef STANDALONE
-# define PROGCLASS             "Discrete"
-# define HACK_INIT             init_discrete
-# define HACK_DRAW             draw_discrete
-# define discrete_opts xlockmore_opts
-# define SMOOTH_COLORS
-# define BRIGHT_COLORS
-# define DEFAULTS              "*delay:  1000 \n" \
-                                               "*count:  4096 \n" \
-                                               "*cycles: 2500 \n" \
-                                               "*ncolors: 100 \n"
+# define MODE_discrete
+#define DEFAULTS       "*delay: 20000 \n" \
+                                       "*count:  4096 \n" \
+                                       "*cycles: 2500 \n" \
+                                       "*ncolors: 100 \n" \
+                                       "*fpsSolid: true \n" \
+                                   "*ignoreRotation: True \n" \
 
+# define SMOOTH_COLORS
+# define release_discrete 0
 # include "xlockmore.h"                /* in xscreensaver distribution */
 # include "erase.h"
-
 #else /* STANDALONE */
 # include "xlock.h"            /* in xlockmore distribution */
 #endif /* STANDALONE */
 
-ModeSpecOpt discrete_opts =
-{0, NULL, 0, NULL, NULL};
+#ifdef MODE_discrete
+
+ENTRYPOINT ModeSpecOpt discrete_opts =
+{0, (XrmOptionDescRec *) NULL, 0, (argtype *) NULL, (OptionStruct *) NULL};
 
 #ifdef USE_MODULES
 ModStruct   discrete_description =
-{"discrete", "init_discrete", "draw_discrete", "release_discrete",
- "refresh_discrete", "init_discrete", NULL, &discrete_opts,
+{"discrete", "init_discrete", "draw_discrete", (char *) NULL,
+ "refresh_discrete", "init_discrete", (char *) NULL, &discrete_opts,
  1000, 4096, 2500, 1, 64, 1.0, "",
  "Shows various discrete maps", 0, NULL};
 
@@ -69,7 +69,7 @@ enum ftypes {
 /*#define TEST STANDARD */
 
 #define BIASES 18
-static int  bias[BIASES] =
+static enum ftypes bias[BIASES] =
 {
        STANDARD, STANDARD, STANDARD, STANDARD,
        SQRT, SQRT, SQRT, SQRT,
@@ -99,25 +99,28 @@ typedef struct {
        enum ftypes op;
        int         count;
        XPoint     *pointBuffer;        /* pointer for XDrawPoints */
+
+    int sqrt_sign, std_sign;
+
+#ifdef STANDALONE
+  eraser_state *eraser;
+#endif
+
 } discretestruct;
 
-static discretestruct *discretes = NULL;
+static discretestruct *discretes = (discretestruct *) NULL;
 
-void
-init_discrete(ModeInfo * mi)
+static void free_discrete(ModeInfo * mi);
+
+ENTRYPOINT void
+init_discrete (ModeInfo * mi)
 {
        double      range;
        discretestruct *hp;
 
-       if (discretes == NULL) {
-               if ((discretes =
-                    (discretestruct *) calloc(MI_NUM_SCREENS(mi),
-                                          sizeof (discretestruct))) == NULL)
-                       return;
-       }
+       MI_INIT (mi, discretes, free_discrete);
        hp = &discretes[MI_SCREEN(mi)];
 
-
        hp->maxx = MI_WIDTH(mi);
        hp->maxy = MI_HEIGHT(mi);
 #ifdef TEST
@@ -239,34 +242,49 @@ init_discrete(ModeInfo * mi)
        hp->pix = 0;
        hp->inc = 0;
 
-       if (hp->pointBuffer == NULL)
-               hp->pointBuffer = (XPoint *) malloc(MI_COUNT(mi) * sizeof (XPoint));
+       if (hp->pointBuffer == NULL) {
+               hp->pointBuffer = (XPoint *) malloc(sizeof (XPoint) * MI_COUNT(mi));
+               /* if fails will check later */
+       }
 
+#ifndef STANDALONE
        /* Clear the background. */
        MI_CLEARWINDOW(mi);
+#endif
 
+       XSetForeground(MI_DISPLAY(mi), MI_GC(mi), MI_WHITE_PIXEL(mi));
        hp->count = 0;
+    hp->sqrt_sign = 1;
+    hp->std_sign = 1;
 }
 
 
-void
-draw_discrete(ModeInfo * mi)
+static void
+draw_discrete_1 (ModeInfo * mi)
 {
        Display    *dsp = MI_DISPLAY(mi);
        Window      win = MI_WINDOW(mi);
        double      oldj, oldi;
-       int         batchcount = MI_COUNT(mi);
+       int         count = MI_COUNT(mi);
        int         cycles = MI_CYCLES(mi);
        int         k;
        XPoint     *xp;
        GC          gc = MI_GC(mi);
-       discretestruct *hp = &discretes[MI_SCREEN(mi)];
+       discretestruct *hp;
+
+       if (discretes == NULL)
+               return;
+       hp = &discretes[MI_SCREEN(mi)];
+       if (hp->pointBuffer == NULL)
+               return;
 
-       k = batchcount;
+       k = count;
        xp = hp->pointBuffer;
 
        hp->inc++;
 
+       MI_IS_DRAWN(mi) = True;
+
        if (MI_NPIXELS(mi) > 2) {
                XSetForeground(dsp, gc, MI_PIXEL(mi, hp->pix));
                if (++hp->pix >= MI_NPIXELS(mi))
@@ -289,18 +307,18 @@ draw_discrete(ModeInfo * mi)
 #endif
 #define HD
 #ifdef HD
-                                       if (k < batchcount / 4) {
-                                               hp->i = ((double) k / batchcount) * 8 - 1;
+                                       if (k < count / 4) {
+                                               hp->i = ((double) k / count) * 8 - 1;
                                                hp->j = 1;
-                                       } else if (k < batchcount / 2) {
+                                       } else if (k < count / 2) {
                                                hp->i = 1;
-                                               hp->j = 3 - ((double) k / batchcount) * 8;
-                                       } else if (k < 3 * batchcount / 4) {
-                                               hp->i = 5 - ((double) k / batchcount) * 8;
+                                               hp->j = 3 - ((double) k / count) * 8;
+                                       } else if (k < 3 * count / 4) {
+                                               hp->i = 5 - ((double) k / count) * 8;
                                                hp->j = -1;
                                        } else {
                                                hp->i = -1;
-                                               hp->j = ((double) k / batchcount) * 8 - 7;
+                                               hp->j = ((double) k / count) * 8 - 7;
                                        }
                                        for (i = 1; i < (hp->inc % 15); i++) {
                                                oldj = hp->j;
@@ -328,11 +346,9 @@ draw_discrete(ModeInfo * mi)
                                        ? sqrt(fabs(hp->b * (hp->i - hp->c)))
                                                         : -sqrt(fabs(hp->b * (hp->i - hp->c))));
                                } else {
-                                       static int  s = 1;
-
-                                       hp->i = s * hp->inc * hp->maxx / cycles / 2;
+                                       hp->i = (hp->sqrt_sign ? 1 : -1) * hp->inc * hp->maxx / cycles / 2;
                                        hp->j = hp->a + hp->i;
-                                       s = -s;
+                                       hp->sqrt_sign = !hp->sqrt_sign;
                                }
                                break;
                        case STANDARD:
@@ -342,11 +358,9 @@ draw_discrete(ModeInfo * mi)
                                        hp->i = oldi + hp->j;
                                        hp->i = fmod(hp->i + 2 * M_PI, 2 * M_PI);
                                } else {
-                                       static int  s = 1;
-
-                                       hp->j = M_PI + fmod(s * hp->inc * 2 * M_PI / (cycles - 0.5), M_PI);
+                                       hp->j = M_PI + fmod((hp->std_sign ? 1 : -1) * hp->inc * 2 * M_PI / (cycles - 0.5), M_PI);
                                        hp->i = M_PI;
-                                       s = -s;
+                                       hp->std_sign = !hp->std_sign;
                                }
                                break;
                        case BIRDIE:
@@ -370,6 +384,8 @@ draw_discrete(ModeInfo * mi)
                                hp->i = ((LRAND() < MAXRAND / 2) ? -1 : 1) *
                                        sqrt(((oldi - hp->a) +
                                              sqrt((oldi - hp->a) * (oldi - hp->a) + (oldj - hp->b) * (oldj - hp->b))) / 2);
+                               if (hp->i < 0.00000001 && hp->i > -0.00000001)
+                                       hp->i = (hp->i > 0.0) ? 0.00000001 : -0.00000001;
                                hp->j = (oldj - hp->b) / (2 * hp->i);
                                break;
                }
@@ -377,34 +393,74 @@ draw_discrete(ModeInfo * mi)
                xp->y = hp->maxy / 2 - (int) ((hp->j - hp->jc) * hp->js);
                xp++;
        }
-       XDrawPoints(dsp, win, gc, hp->pointBuffer, batchcount, CoordModeOrigin);
-       if (++hp->count > cycles) {
-#ifdef STANDALONE
-               erase_full_window(MI_DISPLAY(mi), MI_WINDOW(mi));
-#endif /* STANDALONE */
-               init_discrete(mi);
-       }
+       XDrawPoints(dsp, win, gc, hp->pointBuffer, count, CoordModeOrigin);
 }
 
-void
-release_discrete(ModeInfo * mi)
+ENTRYPOINT void
+draw_discrete (ModeInfo * mi)
 {
-       if (discretes != NULL) {
-               int         screen;
+  discretestruct *hp = &discretes[MI_SCREEN(mi)];
+  int cycles = MI_CYCLES(mi);
+  int i;
+
+  if (hp->eraser) {
+    hp->eraser = erase_window (MI_DISPLAY(mi), MI_WINDOW(mi), hp->eraser);
+    if (!hp->eraser)
+      init_discrete(mi);
+    return;
+  }
+
+  for (i = 0; i < 10; i++) {
+    draw_discrete_1 (mi);
+    hp->count++;
+  }
+
+  if (hp->count > cycles) {
+    hp->eraser = erase_window (MI_DISPLAY(mi), MI_WINDOW(mi), hp->eraser);
+  }
+}
 
-               for (screen = 0; screen < MI_NUM_SCREENS(mi); screen++) {
-                       discretestruct *hp = &discretes[screen];
 
-                       if (hp->pointBuffer != NULL)
-                               (void) free((void *) hp->pointBuffer);
-               }
-               (void) free((void *) discretes);
-               discretes = NULL;
+ENTRYPOINT void
+reshape_discrete(ModeInfo * mi, int width, int height)
+{
+  discretestruct *hp = &discretes[MI_SCREEN(mi)];
+  hp->maxx = width;
+  hp->maxy = height;
+  XClearWindow (MI_DISPLAY (mi), MI_WINDOW(mi));
+}
+
+static void
+free_discrete(ModeInfo * mi)
+{
+       discretestruct *hp = &discretes[MI_SCREEN(mi)];
+
+       if (hp->pointBuffer != NULL) {
+               (void) free((void *) hp->pointBuffer);
+               /* hp->pointBuffer = NULL; */
        }
 }
 
-void
+ENTRYPOINT void
 refresh_discrete(ModeInfo * mi)
 {
        MI_CLEARWINDOW(mi);
 }
+
+ENTRYPOINT Bool
+discrete_handle_event (ModeInfo *mi, XEvent *event)
+{
+  discretestruct *hp = &discretes[MI_SCREEN(mi)];
+  if (screenhack_event_helper (MI_DISPLAY(mi), MI_WINDOW(mi), event))
+    {
+      hp->count = MI_CYCLES(mi);
+      return True;
+    }
+  return False;
+}
+
+
+
+XSCREENSAVER_MODULE ("Discrete", discrete)
+
+#endif /* MODE_discrete */