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authorSimon Rettberg2018-10-16 10:08:48 +0200
committerSimon Rettberg2018-10-16 10:08:48 +0200
commitd3a98cf6cbc3bd0b9efc570f58e8812c03931c18 (patch)
treecbddf8e50f35a9c6e878a5bfe3c6d625d99e12ba /hacks/bubbles.c
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Original 5.40
Diffstat (limited to 'hacks/bubbles.c')
-rw-r--r--hacks/bubbles.c1437
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diff --git a/hacks/bubbles.c b/hacks/bubbles.c
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+/* bubbles.c - frying pan / soft drink in a glass simulation */
+
+/*$Id: bubbles.c,v 1.30 2008/07/31 19:27:48 jwz Exp $*/
+
+/*
+ * Copyright (C) 1995-1996 James Macnicol
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that
+ * copyright notice and this permission notice appear in supporting
+ * documentation. No representations are made about the suitability of this
+ * software for any purpose. It is provided "as is" without express or
+ * implied warranty.
+ */
+
+/*
+ * I got my original inspiration for this by looking at the bottom of a
+ * frying pan while something was cooking and watching the little bubbles
+ * coming off the bottom of the pan as the oil was boiling joining together
+ * to form bigger bubbles and finally to *pop* and disappear. I had some
+ * time on my hands so I wrote this little xscreensaver module to imitate
+ * it. Now that it's done it reminds me more of the bubbles you get in
+ * a glass of fizzy soft drink.....
+ *
+ * The problem seemed to be that the position/size etc. of all the bubbles
+ * on the screen had to be remembered and searched through to find when
+ * bubbles hit each other and combined. To do this more efficiently, the
+ * window/screen is divided up into a square mesh of side length mesh_length
+ * and separate lists of bubbles contained in each cell of the mesh are
+ * kept. Only the cells in the immediate vicinity of the bubble in question
+ * are searched. This should make things more efficient although the whole
+ * thing seems to use up too much CPU, but then I'm using an ancient PC so
+ * perhaps it's not surprising .
+ * (Six months after I wrote the above I now have a Pentium with PCI graphics
+ * and things are _much_ nicer.)
+ *
+ * Author: James Macnicol
+ * Internet E-mail : j-macnicol@adfa.edu.au
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#undef DEBUG /* doesn't compile */
+
+#include <math.h>
+#include <limits.h>
+
+#ifndef VMS
+# include <sys/wait.h>
+#else /* VMS */
+# if __DECC_VER >= 50200000
+# include <sys/wait.h>
+# endif
+#endif /* VMS */
+
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>
+#endif
+
+#include "screenhack.h"
+#include "yarandom.h"
+#include "bubbles.h"
+#include "ximage-loader.h"
+
+#define FANCY_BUBBLES
+
+/*
+ * Public variables
+ */
+
+static const char *bubbles_defaults [] = {
+ ".background: black",
+ ".foreground: white",
+ "*fpsSolid: true",
+ "*simple: false",
+ "*broken: false",
+ "*delay: 10000",
+ "*quiet: false",
+ "*mode: float",
+ "*trails: false",
+ "*3D: false",
+ 0
+};
+
+static XrmOptionDescRec bubbles_options [] = {
+ { "-simple", ".simple", XrmoptionNoArg, "true" },
+#ifdef FANCY_BUBBLES
+ { "-broken", ".broken", XrmoptionNoArg, "true" },
+#endif
+ { "-quiet", ".quiet", XrmoptionNoArg, "true" },
+ { "-3D", ".3D", XrmoptionNoArg, "true" },
+ { "-delay", ".delay", XrmoptionSepArg, 0 },
+ { "-mode", ".mode", XrmoptionSepArg, 0 },
+ { "-drop", ".mode", XrmoptionNoArg, "drop" },
+ { "-rise", ".mode", XrmoptionNoArg, "rise" },
+ { "-trails", ".trails", XrmoptionNoArg, "true" },
+ { 0, 0, 0, 0 }
+};
+
+/*
+ * Private variables
+ */
+
+struct state {
+ Display *dpy;
+ Window window;
+
+ Bubble **mesh;
+ int mesh_length;
+ int mesh_width;
+ int mesh_height;
+ int mesh_cells;
+
+ int **adjacent_list;
+
+ int screen_width;
+ int screen_height;
+ int screen_depth;
+ unsigned int default_fg_pixel, default_bg_pixel;
+
+ int bubble_min_radius; /* For simple mode only */
+ int bubble_max_radius;
+ long *bubble_areas;
+ int *bubble_droppages;
+ GC draw_gc, erase_gc;
+
+#ifdef FANCY_BUBBLES
+ int num_bubble_pixmaps;
+ Bubble_Step **step_pixmaps;
+#endif
+
+ Bool simple;
+ Bool broken;
+ Bool quiet;
+ Bool threed;
+ Bool drop;
+ Bool trails;
+ int drop_dir;
+ int delay;
+};
+
+static int drop_bubble( struct state *st, Bubble *bb );
+
+/*
+ * To prevent forward references, some stuff is up here
+ */
+
+static long
+calc_bubble_area(struct state *st, int r)
+/* Calculate the area of a bubble of radius r */
+{
+#ifdef DEBUG
+ printf("%d %g\n", r,
+ 10.0 * PI * (double)r * (double)r * (double)r);
+#endif /* DEBUG */
+ if (st->threed)
+ return (long)(10.0 * PI * (double)r * (double)r * (double)r);
+ else
+ return (long)(10.0 * PI * (double)r * (double)r);
+}
+
+static void *
+xmalloc(size_t size)
+/* Safe malloc */
+{
+ void *ret;
+
+ if ((ret = malloc(size)) == NULL) {
+ fprintf(stderr, "%s: out of memory\n", progname);
+ exit(1);
+ }
+ return ret;
+}
+
+#ifdef DEBUG
+static void
+die_bad_bubble(Bubble *bb)
+/* This is for use with GDB */
+{
+ fprintf(stderr, "Bad bubble detected at 0x%x!\n", (int)bb);
+ exit(1);
+}
+#endif
+
+static int
+null_bubble(Bubble *bb)
+/* Returns true if the pointer passed is NULL. If not then this checks to
+see if the bubble is valid (i.e. the (x,y) position is valid and the magic
+number is set correctly. This only a sanity check for debugging and is
+turned off if DEBUG isn't set. */
+{
+ if (bb == (Bubble *)NULL)
+ return 1;
+#ifdef DEBUG
+ if ((bb->cell_index < 0) || (bb->cell_index > st->mesh_cells)) {
+ fprintf(stderr, "cell_index = %d\n", bb->cell_index);
+ die_bad_bubble(bb);
+ }
+ if (bb->magic != BUBBLE_MAGIC) {
+ fprintf(stderr, "Magic = %d\n", bb->magic);
+ die_bad_bubble(bb);
+ }
+ if (st->simple) {
+ if ((bb->x < 0) || (bb->x > st->screen_width) ||
+ (bb->y < 0) || (bb->y > st->screen_height) ||
+ (bb->radius < st->bubble_min_radius) || (bb->radius >
+ st->bubble_max_radius)) {
+ fprintf(stderr,
+ "radius = %d, x = %d, y = %d, magic = %d, cell index = %d\n",
+ bb->radius, bb->x, bb->y, bb->magic, bb->cell_index);
+ die_bad_bubble(bb);
+ }
+#ifdef FANCY_BUBBLES
+ } else {
+ if ((bb->x < 0) || (bb->x > st->screen_width) ||
+ (bb->y < 0) || (bb->y > st->screen_height) ||
+ (bb->radius < st->step_pixmaps[0]->radius) ||
+ (bb->radius > st->step_pixmaps[st->num_bubble_pixmaps-1]->radius)) {
+ fprintf(stderr,
+ "radius = %d, x = %d, y = %d, magic = %d, cell index = %d\n",
+ bb->radius, bb->x, bb->y, bb->magic, bb->cell_index);
+ die_bad_bubble(bb);
+ }
+#endif
+ }
+#endif /* DEBUG */
+ return 0;
+}
+
+#ifdef DEBUG
+static void
+print_bubble_list(Bubble *bb)
+/* Print list of where all the bubbles are. For debugging purposes only. */
+{
+ if (! null_bubble(bb)) {
+ printf(" (%d, %d) %d\n", bb->x, bb->y, bb->radius);
+ print_bubble_list(bb->next);
+ }
+}
+#endif /* DEBUG */
+
+static void
+add_bubble_to_list(Bubble **list, Bubble *bb)
+/* Take a pointer to a list of bubbles and stick bb at the head of the
+ list. */
+{
+ Bubble *head = *list;
+
+ if (null_bubble(head)) {
+ bb->prev = (Bubble *)NULL;
+ bb->next = (Bubble *)NULL;
+ } else {
+ bb->next = head;
+ bb->prev = (Bubble *)NULL;
+ head->prev = bb;
+ }
+ *list = bb;
+}
+
+
+/*
+ * Mesh stuff
+ */
+
+
+static void
+init_mesh (struct state *st)
+/* Setup the mesh of bubbles */
+{
+ int i;
+
+ st->mesh = (Bubble **)xmalloc(st->mesh_cells * sizeof(Bubble *));
+ for (i = 0; i < st->mesh_cells; i++)
+ st->mesh[i] = (Bubble *)NULL;
+}
+
+static int
+cell_to_mesh(struct state *st, int x, int y)
+/* convert cell coordinates to mesh index */
+{
+#ifdef DEBUG
+ if ((x < 0) || (y < 0)) {
+ fprintf(stderr, "cell_to_mesh: x = %d, y = %d\n", x, y);
+ exit(1);
+ }
+#endif
+ return ((st->mesh_width * y) + x);
+}
+
+static void
+mesh_to_cell(struct state *st, int mi, int *cx, int *cy)
+/* convert mesh index into cell coordinates */
+{
+ *cx = mi % st->mesh_width;
+ *cy = mi / st->mesh_width;
+}
+
+static int
+pixel_to_mesh(struct state *st, int x, int y)
+/* convert screen coordinates into mesh index */
+{
+ return cell_to_mesh(st, (x / st->mesh_length), (y / st->mesh_length));
+}
+
+static int
+verify_mesh_index(struct state *st, int x, int y)
+/* check to see if (x,y) is in the mesh */
+{
+ if ((x < 0) || (y < 0) || (x >= st->mesh_width) || (y >= st->mesh_height))
+ return (-1);
+ return (cell_to_mesh(st, x, y));
+}
+
+#ifdef DEBUG
+static void
+print_adjacents(int *adj)
+/* Print a list of the cells calculated above. For debugging only. */
+{
+ int i;
+
+ printf("(");
+ for (i = 0; i < 8; i++)
+ printf("%d ", adj[i]);
+ printf(")\n");
+}
+#endif /* DEBUG */
+
+static void
+add_to_mesh(struct state *st, Bubble *bb)
+/* Add the given bubble to the mesh by sticking it on the front of the
+list. bb is already allocated so no need to malloc() anything, just
+adjust pointers. */
+{
+#ifdef DEBUG
+ if (null_bubble(bb)) {
+ fprintf(stderr, "Bad bubble passed to add_to_mesh()!\n");
+ exit(1);
+ }
+#endif /* DEBUG */
+
+ add_bubble_to_list(&st->mesh[bb->cell_index], bb);
+}
+
+#ifdef DEBUG
+static void
+print_mesh (struct state *st)
+/* Print the contents of the mesh */
+{
+ int i;
+
+ for (i = 0; i < st->mesh_cells; i++) {
+ if (! null_bubble(st->mesh[i])) {
+ printf("Mesh cell %d\n", i);
+ print_bubble_list(st->mesh[i]);
+ }
+ }
+}
+
+static void
+valid_mesh (struct state *st)
+/* Check to see if the mesh is Okay. For debugging only. */
+{
+ int i;
+ Bubble *b;
+
+ for (i = 0; i < st->mesh_cells; i++) {
+ b = st->mesh[i];
+ while (! null_bubble(b))
+ b = b->next;
+ }
+}
+
+static int
+total_bubbles (struct state *st)
+/* Count how many bubbles there are in total. For debugging only. */
+{
+ int rv = 0;
+ int i;
+ Bubble *b;
+
+ for (i = 0; i < st->mesh_cells; i++) {
+ b = st->mesh[i];
+ while (! null_bubble(b)) {
+ rv++;
+ b = b->next;
+ }
+ }
+
+ return rv;
+}
+#endif /* DEBUG */
+
+static void
+calculate_adjacent_list (struct state *st)
+/* Calculate the list of cells adjacent to a particular cell for use
+ later. */
+{
+ int i;
+ int ix, iy;
+
+ st->adjacent_list = (int **)xmalloc(st->mesh_cells * sizeof(int *));
+ for (i = 0; i < st->mesh_cells; i++) {
+ st->adjacent_list[i] = (int *)xmalloc(9 * sizeof(int));
+ mesh_to_cell(st, i, &ix, &iy);
+ st->adjacent_list[i][0] = verify_mesh_index(st, --ix, --iy);
+ st->adjacent_list[i][1] = verify_mesh_index(st, ++ix, iy);
+ st->adjacent_list[i][2] = verify_mesh_index(st, ++ix, iy);
+ st->adjacent_list[i][3] = verify_mesh_index(st, ix, ++iy);
+ st->adjacent_list[i][4] = verify_mesh_index(st, ix, ++iy);
+ st->adjacent_list[i][5] = verify_mesh_index(st, --ix, iy);
+ st->adjacent_list[i][6] = verify_mesh_index(st, --ix, iy);
+ st->adjacent_list[i][7] = verify_mesh_index(st, ix, --iy);
+ st->adjacent_list[i][8] = i;
+ }
+}
+
+static void
+adjust_areas (struct state *st)
+/* Adjust areas of bubbles so we don't get overflow in weighted_mean() */
+{
+ double maxvalue;
+ long maxarea;
+ long factor;
+ int i;
+
+#ifdef FANCY_BUBBLES
+ if (st->simple)
+ maxarea = st->bubble_areas[st->bubble_max_radius+1];
+ else
+ maxarea = st->step_pixmaps[st->num_bubble_pixmaps]->area;
+#else /* !FANCY_BUBBLES */
+ maxarea = st->bubble_areas[st->bubble_max_radius+1];
+#endif /* !FANCY_BUBBLES */
+ maxvalue = (double)st->screen_width * 2.0 * (double)maxarea;
+ factor = (long)ceil(maxvalue / (double)LONG_MAX);
+ if (factor > 1) {
+ /* Overflow will occur in weighted_mean(). We must divide areas
+ each by factor so it will never do so. */
+#ifdef FANCY_BUBBLES
+ if (st->simple) {
+ for (i = st->bubble_min_radius; i <= st->bubble_max_radius+1; i++) {
+ st->bubble_areas[i] /= factor;
+ if (st->bubble_areas[i] == 0)
+ st->bubble_areas[i] = 1;
+ }
+ } else {
+ for (i = 0; i <= st->num_bubble_pixmaps; i++) {
+#ifdef DEBUG
+ printf("area = %ld", st->step_pixmaps[i]->area);
+#endif /* DEBUG */
+ st->step_pixmaps[i]->area /= factor;
+ if (st->step_pixmaps[i]->area == 0)
+ st->step_pixmaps[i]->area = 1;
+#ifdef DEBUG
+ printf("-> %ld\n", st->step_pixmaps[i]->area);
+#endif /* DEBUG */
+ }
+ }
+#else /* !FANCY_BUBBLES */
+ for (i = st->bubble_min_radius; i <= st->bubble_max_radius+1; i++) {
+ st->bubble_areas[i] /= factor;
+ if (st->bubble_areas[i] == 0)
+ st->bubble_areas[i] = 1;
+ }
+#endif /* !FANCY_BUBBLES */
+ }
+#ifdef DEBUG
+ printf("maxarea = %ld\n", maxarea);
+ printf("maxvalue = %g\n", maxvalue);
+ printf("LONG_MAX = %ld\n", LONG_MAX);
+ printf("factor = %ld\n", factor);
+#endif /* DEBUG */
+}
+
+/*
+ * Bubbles stuff
+ */
+
+static Bubble *
+new_bubble (struct state *st)
+/* Add a new bubble at some random position on the screen of the smallest
+size. */
+{
+ Bubble *rv = (Bubble *)xmalloc(sizeof(Bubble));
+
+ /* Can't use null_bubble() here since magic number hasn't been set */
+ if (rv == (Bubble *)NULL) {
+ fprintf(stderr, "Ran out of memory!\n");
+ exit(1);
+ }
+
+ if (st->simple) {
+ rv->radius = st->bubble_min_radius;
+ rv->area = st->bubble_areas[st->bubble_min_radius];
+#ifdef FANCY_BUBBLES
+ } else {
+ rv->step = 0;
+ rv->radius = st->step_pixmaps[0]->radius;
+ rv->area = st->step_pixmaps[0]->area;
+#endif /* FANCY_BUBBLES */
+ }
+ rv->visible = 0;
+ rv->magic = BUBBLE_MAGIC;
+ rv->x = random() % st->screen_width;
+ rv->y = random() % st->screen_height;
+ rv->cell_index = pixel_to_mesh(st, rv->x, rv->y);
+
+ return rv;
+}
+
+static void
+show_bubble(struct state *st, Bubble *bb)
+/* paint the bubble on the screen */
+{
+ if (null_bubble(bb)) {
+ fprintf(stderr, "NULL bubble passed to show_bubble\n");
+ exit(1);
+ }
+
+ if (! bb->visible) {
+ bb->visible = 1;
+
+ if (st->simple) {
+ XDrawArc(st->dpy, st->window, st->draw_gc, (bb->x - bb->radius),
+ (bb->y - bb->radius), bb->radius*2, bb->radius*2, 0,
+ 360*64);
+ } else {
+#ifdef FANCY_BUBBLES
+ XSetClipOrigin(st->dpy, st->step_pixmaps[bb->step]->draw_gc,
+ (bb->x - bb->radius),
+ (bb->y - bb->radius));
+
+ XCopyArea(st->dpy, st->step_pixmaps[bb->step]->ball, st->window,
+ st->step_pixmaps[bb->step]->draw_gc,
+ 0, 0, (bb->radius * 2),
+ (bb->radius * 2),
+ (bb->x - bb->radius),
+ (bb->y - bb->radius));
+#endif /* FANCY_BUBBLES */
+ }
+ }
+}
+
+static void
+hide_bubble(struct state *st, Bubble *bb)
+/* erase the bubble */
+{
+ if (null_bubble(bb)) {
+ fprintf(stderr, "NULL bubble passed to hide_bubble\n");
+ exit(1);
+ }
+
+ if (bb->visible) {
+ bb->visible = 0;
+
+ if (st->simple) {
+ XDrawArc(st->dpy, st->window, st->erase_gc, (bb->x - bb->radius),
+ (bb->y - bb->radius), bb->radius*2, bb->radius*2, 0,
+ 360*64);
+ } else {
+#ifdef FANCY_BUBBLES
+ if (! st->broken) {
+ XSetClipOrigin(st->dpy, st->step_pixmaps[bb->step]->erase_gc,
+ (bb->x - bb->radius), (bb->y - bb->radius));
+
+ XFillRectangle(st->dpy, st->window, st->step_pixmaps[bb->step]->erase_gc,
+ (bb->x - bb->radius),
+ (bb->y - bb->radius),
+ (bb->radius * 2),
+ (bb->radius * 2));
+ }
+#endif /* FANCY_BUBBLES */
+ }
+ }
+}
+
+static void
+delete_bubble_in_mesh(struct state *st, Bubble *bb, int keep_bubble)
+/* Delete an individual bubble, adjusting list of bubbles around it.
+ If keep_bubble is true then the bubble isn't actually deleted. We
+ use this to allow bubbles to change mesh cells without reallocating,
+ (it needs this when two bubbles collide and the centre position is
+ recalculated, and this may stray over a mesh boundary). */
+{
+ if ((!null_bubble(bb->prev)) && (!null_bubble(bb->next))) {
+ bb->prev->next = bb->next;
+ bb->next->prev = bb->prev;
+ } else if ((!null_bubble(bb->prev)) &&
+ (null_bubble(bb->next))) {
+ bb->prev->next = (Bubble *)NULL;
+ bb->next = st->mesh[bb->cell_index];
+ } else if ((null_bubble(bb->prev)) &&
+ (!null_bubble(bb->next))) {
+ bb->next->prev = (Bubble *)NULL;
+ st->mesh[bb->cell_index] = bb->next;
+ bb->next = st->mesh[bb->cell_index];
+ } else {
+ /* Only item on list */
+ st->mesh[bb->cell_index] = (Bubble *)NULL;
+ }
+ if (! keep_bubble)
+ free(bb);
+}
+
+static unsigned long
+ulongsqrint(int x)
+/* Saves ugly inline code */
+{
+ return ((unsigned long)x * (unsigned long)x);
+}
+
+static Bubble *
+get_closest_bubble(struct state *st, Bubble *bb)
+/* Find the closest bubble touching the this bubble, NULL if none are
+ touching. */
+{
+ Bubble *rv = (Bubble *)NULL;
+ Bubble *tmp;
+ unsigned long separation2, touchdist2;
+ int dx, dy;
+ unsigned long closest2 = ULONG_MAX;
+ int i;
+
+#ifdef DEBUG
+ if (null_bubble(bb)) {
+ fprintf(stderr, "NULL pointer 0x%x passed to get_closest_bubble()!",
+ (int)bb);
+ exit(1);
+ }
+#endif /* DEBUG */
+
+ for (i = 0; i < 9; i++) {
+ /* There is a bug here where bb->cell_index is negaitve.. */
+#ifdef DEBUG
+ if ((bb->cell_index < 0) || (bb->cell_index >= st->mesh_cells)) {
+ fprintf(stderr, "bb->cell_index = %d\n", bb->cell_index);
+ exit(1);
+ }
+#endif /* DEBUG */
+/* printf("%d,", bb->cell_index); */
+ if (st->adjacent_list[bb->cell_index][i] != -1) {
+ tmp = st->mesh[st->adjacent_list[bb->cell_index][i]];
+ while (! null_bubble(tmp)) {
+ if (tmp != bb) {
+ dx = tmp->x - bb->x;
+ dy = tmp->y - bb->y;
+ separation2 = ulongsqrint(dx) + ulongsqrint(dy);
+ /* Add extra leeway so circles _never_ overlap */
+ touchdist2 = ulongsqrint(tmp->radius + bb->radius + 2);
+ if ((separation2 <= touchdist2) && (separation2 <
+ closest2)) {
+ rv = tmp;
+ closest2 = separation2;
+ }
+ }
+ tmp = tmp->next;
+ }
+ }
+ }
+
+ return rv;
+}
+
+#ifdef DEBUG
+static void
+ldr_barf (struct state *st)
+{
+}
+#endif /* DEBUG */
+
+static long
+long_div_round(long num, long dem)
+{
+ long divvie, moddo;
+
+#ifdef DEBUG
+ if ((num < 0) || (dem < 0)) {
+ fprintf(stderr, "long_div_round: %ld, %ld\n", num, dem);
+ ldr_barf();
+ exit(1);
+ }
+#endif /* DEBUG */
+
+ divvie = num / dem;
+ moddo = num % dem;
+ if (moddo > (dem / 2))
+ ++divvie;
+
+#ifdef DEBUG
+ if ((divvie < 0) || (moddo < 0)) {
+ fprintf(stderr, "long_div_round: %ld, %ld\n", divvie, moddo);
+ ldr_barf();
+ exit(1);
+ }
+#endif /* DEBUG */
+
+ return divvie;
+}
+
+static int
+weighted_mean(int n1, int n2, long w1, long w2)
+/* Mean of n1 and n2 respectively weighted by weights w1 and w2. */
+{
+#ifdef DEBUG
+ if ((w1 <= 0) || (w2 <= 0)) {
+ fprintf(stderr,
+ "Bad weights passed to weighted_mean() - (%d, %d, %ld, %ld)!\n",
+ n1, n2, w1, w2);
+ exit(1);
+ }
+#endif /* DEBUG */
+ return ((int)long_div_round((long)n1 * w1 + (long)n2 * w2,
+ w1 + w2));
+}
+
+static int
+bubble_eat(struct state *st, Bubble *diner, Bubble *food)
+/* The diner eats the food. Returns true (1) if the diner still exists */
+{
+ int i;
+ int newmi;
+
+#ifdef DEBUG
+ if ((null_bubble(diner)) || (null_bubble(food))) {
+ fprintf(stderr, "Bad bubbles passed to bubble_eat()!\n");
+ exit(1);
+ }
+#endif /* DEBUG */
+
+ /* We hide the diner even in the case that it doesn't grow so that
+ if the food overlaps its boundary it is replaced. This could
+ probably be solved by letting bubbles eat others which are close
+ but not quite touching. It's probably worth it, too, since we
+ would then not have to redraw bubbles which don't change in
+ size. */
+
+ hide_bubble(st, diner);
+ hide_bubble(st, food);
+ diner->x = weighted_mean(diner->x, food->x, diner->area, food->area);
+ diner->y = weighted_mean(diner->y, food->y, diner->area, food->area);
+ newmi = pixel_to_mesh(st, diner->x, diner->y);
+ diner->area += food->area;
+ delete_bubble_in_mesh(st, food, DELETE_BUBBLE);
+
+ if (st->drop) {
+ if ((st->simple) && (diner->area > st->bubble_areas[st->bubble_max_radius])) {
+ diner->area = st->bubble_areas[st->bubble_max_radius];
+ }
+#ifdef FANCY_BUBBLES
+ if ((! st->simple) && (diner->area > st->step_pixmaps[st->num_bubble_pixmaps]->area)) {
+ diner->area = st->step_pixmaps[st->num_bubble_pixmaps]->area;
+ }
+#endif /* FANCY_BUBBLES */
+ }
+ else {
+ if ((st->simple) && (diner->area > st->bubble_areas[st->bubble_max_radius])) {
+ delete_bubble_in_mesh(st, diner, DELETE_BUBBLE);
+ return 0;
+ }
+#ifdef FANCY_BUBBLES
+ if ((! st->simple) && (diner->area >
+ st->step_pixmaps[st->num_bubble_pixmaps]->area)) {
+ delete_bubble_in_mesh(st, diner, DELETE_BUBBLE);
+ return 0;
+ }
+#endif /* FANCY_BUBBLES */
+ }
+
+ if (st->simple) {
+ if (diner->area > st->bubble_areas[diner->radius + 1]) {
+ /* Move the bubble to a new radius */
+ i = diner->radius;
+ while ((i < st->bubble_max_radius - 1) && (diner->area > st->bubble_areas[i+1]))
+ ++i;
+ diner->radius = i;
+ }
+ show_bubble(st, diner);
+#ifdef FANCY_BUBBLES
+ } else {
+ if (diner->area > st->step_pixmaps[diner->step+1]->area) {
+ i = diner->step;
+ while ((i < st->num_bubble_pixmaps - 1) && (diner->area > st->step_pixmaps[i+1]->area))
+ ++i;
+ diner->step = i;
+ diner->radius = st->step_pixmaps[diner->step]->radius;
+ }
+ show_bubble(st, diner);
+#endif /* FANCY_BUBBLES */
+ }
+
+ /* Now adjust locations and cells if need be */
+ if (newmi != diner->cell_index) {
+ delete_bubble_in_mesh(st, diner, KEEP_BUBBLE);
+ diner->cell_index = newmi;
+ add_to_mesh(st, diner);
+ }
+
+ return 1;
+}
+
+static int
+merge_bubbles(struct state *st, Bubble *b1, Bubble *b2)
+/* These two bubbles merge into one. If the first one wins out return
+1 else return 2. If there is no winner (it explodes) then return 0 */
+{
+ int b1size, b2size;
+
+ b1size = b1->area;
+ b2size = b2->area;
+
+#ifdef DEBUG
+ if ((null_bubble(b1) || null_bubble(b2))) {
+ fprintf(stderr, "NULL bubble passed to merge_bubbles()!\n");
+ exit(1);
+ }
+#endif /* DEBUG */
+
+ if (b1 == b2) {
+ hide_bubble(st, b1);
+ delete_bubble_in_mesh(st, b1, DELETE_BUBBLE);
+ return 0;
+ }
+
+ if (b1size > b2size) {
+ switch (bubble_eat(st, b1, b2)) {
+ case 0:
+ return 0;
+ break;
+ case 1:
+ return 1;
+ break;
+ default:
+ break;
+ }
+ } else if (b1size < b2size) {
+ switch (bubble_eat(st, b2, b1)) {
+ case 0:
+ return 0;
+ break;
+ case 1:
+ return 2;
+ break;
+ default:
+ break;
+ }
+ } else {
+ if ((random() % 2) == 0) {
+ switch (bubble_eat(st, b1, b2)) {
+ case 0:
+ return 0;
+ break;
+ case 1:
+ return 1;
+ break;
+ default:
+ break;
+ }
+ } else {
+ switch (bubble_eat(st, b2, b1)) {
+ case 0:
+ return 0;
+ break;
+ case 1:
+ return 2;
+ break;
+ default:
+ break;
+ }
+ }
+ }
+ fprintf(stderr, "An error occurred in merge_bubbles()\n");
+ exit(1);
+}
+
+static void
+insert_new_bubble(struct state *st, Bubble *tmp)
+/* Calculates which bubbles are eaten when a new bubble tmp is
+ inserted. This is called recursively in case when a bubble grows
+ it eats others. Careful to pick out disappearing bubbles. */
+{
+ Bubble *nextbub;
+ Bubble *touch;
+
+#ifdef DEBUG
+ if (null_bubble(tmp)) {
+ fprintf(stderr, "Bad bubble passed to insert_new_bubble()!\n");
+ exit(1);
+ }
+#endif /* DEBUG */
+
+ nextbub = tmp;
+ touch = get_closest_bubble(st, nextbub);
+ if (null_bubble(touch))
+ return;
+
+ while (1) {
+
+ /* Merge all touching bubbles */
+ while (! null_bubble(touch)) {
+ switch (merge_bubbles(st, nextbub, touch)) {
+ case 2:
+ /* touch ate nextbub and survived */
+ nextbub = touch;
+ break;
+ case 1:
+ /* nextbub ate touch and survived */
+ break;
+ case 0:
+ /* somebody ate someone else but they exploded */
+ nextbub = (Bubble *)NULL;
+ break;
+ default:
+ /* something went wrong */
+ fprintf(stderr, "Error occurred in insert_new_bubble()\n");
+ exit(1);
+ }
+
+ /* Check to see if any bubble survived. */
+ if (null_bubble(nextbub))
+ break;
+
+ /* Check to see if there are any other bubbles still in the area
+ and if we need to do this all over again for them. */
+ touch = get_closest_bubble(st, nextbub);
+ }
+
+ if (null_bubble(nextbub))
+ break;
+
+ /* Shift bubble down. Break if we run off the screen. */
+ if (st->drop) {
+ if (drop_bubble( st, nextbub ) == -1)
+ break;
+ }
+
+ /* Check to see if there are any other bubbles still in the area
+ and if we need to do this all over again for them. */
+ touch = get_closest_bubble(st, nextbub);
+ if (null_bubble(touch)) {
+ /* We also continue every so often if we're dropping and the bubble is at max size */
+ if (st->drop) {
+ if (st->simple) {
+ if ((nextbub->area >= st->bubble_areas[st->bubble_max_radius - 1]) && (random() % 2 == 0))
+ continue;
+ }
+#ifdef FANCY_BUBBLES
+ else {
+ if ((nextbub->step >= st->num_bubble_pixmaps - 1) && (random() % 2 == 0))
+ continue;
+ }
+#endif /* FANCY_BUBBLES */
+ }
+ break;
+ }
+
+ }
+}
+
+
+static void
+leave_trail(struct state *st, Bubble *bb )
+{
+ Bubble *tmp;
+
+ tmp = new_bubble(st);
+ tmp->x = bb->x;
+ tmp->y = bb->y - ((bb->radius + 10) * st->drop_dir);
+ tmp->cell_index = pixel_to_mesh(st, tmp->x, tmp->y);
+ add_to_mesh(st, tmp);
+ insert_new_bubble(st, tmp);
+ show_bubble( st, tmp );
+}
+
+
+static int
+drop_bubble( struct state *st, Bubble *bb )
+{
+ int newmi;
+
+ hide_bubble( st, bb );
+
+ if (st->simple)
+ (bb->y) += (st->bubble_droppages[bb->radius] * st->drop_dir);
+#ifdef FANCY_BUBBLES
+ else
+ (bb->y) += (st->step_pixmaps[bb->step]->droppage * st->drop_dir);
+#endif /* FANCY_BUBBLES */
+ if ((bb->y < 0) || (bb->y > st->screen_height)) {
+ delete_bubble_in_mesh( st, bb, DELETE_BUBBLE );
+ return -1;
+ }
+
+ show_bubble( st, bb );
+
+ /* Now adjust locations and cells if need be */
+ newmi = pixel_to_mesh(st, bb->x, bb->y);
+ if (newmi != bb->cell_index) {
+ delete_bubble_in_mesh(st, bb, KEEP_BUBBLE);
+ bb->cell_index = newmi;
+ add_to_mesh(st, bb);
+ }
+
+ if (st->trails) {
+ if (st->simple) {
+ if ((bb->area >= st->bubble_areas[st->bubble_max_radius - 1]) && (random() % 2 == 0))
+ leave_trail( st, bb );
+ }
+#ifdef FANCY_BUBBLES
+ else {
+ if ((bb->step >= st->num_bubble_pixmaps - 1) && (random() % 2 == 0))
+ leave_trail( st, bb );
+ }
+#endif /* FANCY_BUBBLES */
+ }
+
+ return 0;
+}
+
+
+#ifdef DEBUG
+static int
+get_length_of_bubble_list(Bubble *bb)
+{
+ Bubble *tmp = bb;
+ int rv = 0;
+
+ while (! null_bubble(tmp)) {
+ rv++;
+ tmp = tmp->next;
+ }
+
+ return rv;
+}
+#endif /* DEBUG */
+
+/*
+ * Pixmap stuff used regardless of whether file I/O is available. Must
+ * still check for XPM, though!
+ */
+
+#ifdef FANCY_BUBBLES
+
+/*
+ * Pixmaps without file I/O (but do have XPM)
+ */
+
+static void
+pixmap_sort(Bubble_Step **head, int numelems)
+/* Couldn't get qsort to work right with this so I wrote my own. This puts
+the numelems length array with first element at head into order of radius.
+*/
+{
+ Bubble_Step tmp;
+ Bubble_Step *least = 0;
+ int minradius = INT_MAX;
+ int i;
+
+ for (i = 0; i < numelems; i++) {
+ if (head[i]->radius < minradius) {
+ least = head[i];
+ minradius = head[i]->radius;
+ }
+ }
+ if (*head != least) {
+ memcpy(&tmp, least, sizeof(Bubble_Step));
+ memcpy(least, *head, sizeof(Bubble_Step));
+ memcpy(*head, &tmp, sizeof(Bubble_Step));
+ }
+
+ if (numelems > 2)
+ pixmap_sort(&head[1], numelems-1);
+}
+
+static int
+extrapolate(int i1, int i2)
+{
+ return (i2 + (i2 - i1));
+}
+
+static void
+make_pixmap_array(struct state *st, Bubble_Step *list)
+/* From a linked list of bubbles construct the array step_pixmaps */
+{
+ Bubble_Step *tmp = list;
+ int ind;
+#ifdef DEBUG
+ int prevrad = -1;
+#endif
+
+ if (list == (Bubble_Step *)NULL) {
+ fprintf(stderr, "NULL list passed to make_pixmap_array\n");
+ exit(1);
+ }
+
+ st->num_bubble_pixmaps = 1;
+ while(tmp->next != (Bubble_Step *)NULL) {
+ tmp = tmp->next;
+ ++st->num_bubble_pixmaps;
+ }
+
+ if (st->num_bubble_pixmaps < 2) {
+ fprintf(stderr, "Must be at least two bubbles in file\n");
+ exit(1);
+ }
+
+ st->step_pixmaps = (Bubble_Step **)xmalloc((st->num_bubble_pixmaps + 1) *
+ sizeof(Bubble_Step *));
+
+ /* Copy them blindly into the array for sorting. */
+ ind = 0;
+ tmp = list;
+ do {
+ st->step_pixmaps[ind++] = tmp;
+ tmp = tmp->next;
+ } while(tmp != (Bubble_Step *)NULL);
+
+ /* We make another bubble beyond the ones with pixmaps so that the final
+ bubble hangs around and doesn't pop immediately. It's radius and area
+ are found by extrapolating from the largest two bubbles with pixmaps. */
+
+ st->step_pixmaps[st->num_bubble_pixmaps] =
+ (Bubble_Step *)xmalloc(sizeof(Bubble_Step));
+ st->step_pixmaps[st->num_bubble_pixmaps]->radius = INT_MAX;
+
+ pixmap_sort(st->step_pixmaps, (st->num_bubble_pixmaps + 1));
+
+#ifdef DEBUG
+ if (st->step_pixmaps[st->num_bubble_pixmaps]->radius != INT_MAX) {
+ fprintf(stderr, "pixmap_sort() screwed up make_pixmap_array\n");
+ }
+#endif /* DEBUG */
+
+ st->step_pixmaps[st->num_bubble_pixmaps]->radius =
+ extrapolate(st->step_pixmaps[st->num_bubble_pixmaps-2]->radius,
+ st->step_pixmaps[st->num_bubble_pixmaps-1]->radius);
+ st->step_pixmaps[st->num_bubble_pixmaps]->area =
+ calc_bubble_area(st, st->step_pixmaps[st->num_bubble_pixmaps]->radius);
+
+
+#ifdef DEBUG
+ /* Now check for correct order */
+ for (ind = 0; ind < st->num_bubble_pixmaps; ind++) {
+ if (prevrad > 0) {
+ if (st->step_pixmaps[ind]->radius < prevrad) {
+ fprintf(stderr, "Pixmaps not in ascending order of radius\n");
+ exit(1);
+ }
+ }
+ prevrad = st->step_pixmaps[ind]->radius;
+ }
+#endif /* DEBUG */
+
+ /* Now populate the droppage values */
+ for (ind = 0; ind < st->num_bubble_pixmaps; ind++)
+ st->step_pixmaps[ind]->droppage = MAX_DROPPAGE * ind / st->num_bubble_pixmaps;
+}
+
+static void
+make_pixmap_from_default(struct state *st,
+ const unsigned char *png_data,
+ unsigned long data_size,
+ Bubble_Step *bl)
+/* Read pixmap data which has been compiled into the program and a pointer
+ to which has been passed.
+
+ This is virtually copied verbatim from make_pixmap_from_file() above and
+changes made to either should be propagated onwards! */
+{
+ XGCValues gcv;
+
+#ifdef DEBUG
+ if (pixmap_data == (char **)0) {
+ fprintf(stderr, "make_pixmap_from_default(): NULL passed\n");
+ exit(1);
+ }
+#endif
+
+ if (bl == (Bubble_Step *)NULL) {
+ fprintf(stderr, "NULL pointer passed to make_pixmap()\n");
+ exit(1);
+ }
+
+#ifdef FANCY_BUBBLES
+ {
+ int w, h;
+ bl->ball = image_data_to_pixmap (st->dpy, st->window, png_data, data_size,
+ &w, &h, &bl->shape_mask);
+ bl->radius = MAX(w, h) / 2;
+ bl->area = calc_bubble_area(st, bl->radius);
+ }
+#endif /* FANCY_BUBBLES */
+
+ gcv.foreground = st->default_fg_pixel;
+ gcv.function = GXcopy;
+ bl->draw_gc = XCreateGC (st->dpy, st->window, GCForeground, &gcv);
+ XSetClipMask(st->dpy, bl->draw_gc, bl->shape_mask);
+
+ gcv.foreground = st->default_bg_pixel;
+ gcv.function = GXcopy;
+ bl->erase_gc = XCreateGC (st->dpy, st->window, GCForeground, &gcv);
+ XSetClipMask(st->dpy, bl->erase_gc, bl->shape_mask);
+}
+
+static void
+default_to_pixmaps (struct state *st)
+/* Make pixmaps out of default ball data stored in bubbles_default.c */
+{
+ int i;
+ Bubble_Step *pixmap_list = (Bubble_Step *)NULL;
+ Bubble_Step *newpix, *tmppix;
+
+ init_default_bubbles();
+
+ for (i = 0; i < num_default_bubbles; i++) {
+ newpix = (Bubble_Step *)xmalloc(sizeof(Bubble_Step));
+ make_pixmap_from_default(st,
+ default_bubbles[i].png,
+ default_bubbles[i].size,
+ newpix);
+ /* Now add to list */
+ if (pixmap_list == (Bubble_Step *)NULL) {
+ pixmap_list = newpix;
+ } else {
+ tmppix = pixmap_list;
+ while (tmppix->next != (Bubble_Step *)NULL)
+ tmppix = tmppix->next;
+ tmppix->next = newpix;
+ }
+ newpix->next = (Bubble_Step *)NULL;
+ }
+
+ /* Finally construct step_pixmaps[] */
+ make_pixmap_array(st, pixmap_list);
+}
+
+#endif /* FANCY_BUBBLES */
+
+
+/*
+ * Main stuff
+ */
+
+
+static void
+get_resources(struct state *st)
+/* Get the appropriate X resources and warn about any inconsistencies. */
+{
+ Bool rise;
+ XWindowAttributes xgwa;
+ Colormap cmap;
+ char *s;
+ XGetWindowAttributes (st->dpy, st->window, &xgwa);
+ cmap = xgwa.colormap;
+
+ st->threed = get_boolean_resource(st->dpy, "3D", "Boolean");
+ st->quiet = get_boolean_resource(st->dpy, "quiet", "Boolean");
+ st->simple = get_boolean_resource(st->dpy, "simple", "Boolean");
+ /* Forbid rendered bubbles on monochrome displays */
+ if ((mono_p) && (! st->simple)) {
+ if (! st->quiet)
+ fprintf(stderr,
+ "Rendered bubbles not supported on monochrome displays\n");
+ st->simple = True;
+ }
+ st->delay = get_integer_resource(st->dpy, "delay", "Integer");
+
+ s = get_string_resource (st->dpy, "mode", "Mode");
+ rise = False;
+ if (!s || !*s || !strcasecmp (s, "float"))
+ ;
+ else if (!strcasecmp (s, "rise"))
+ rise = True;
+ else if (!strcasecmp (s, "drop"))
+ st->drop = True;
+ else
+ fprintf (stderr, "%s: bogus mode: \"%s\"\n", progname, s);
+
+ st->trails = get_boolean_resource(st->dpy, "trails", "Boolean");
+ st->drop_dir = (st->drop ? 1 : -1);
+ if (st->drop || rise)
+ st->drop = 1;
+
+ st->default_fg_pixel = get_pixel_resource (st->dpy,
+ cmap, "foreground", "Foreground");
+ st->default_bg_pixel = get_pixel_resource (st->dpy,
+ cmap, "background", "Background");
+
+ if (st->simple) {
+ /* This is easy */
+ st->broken = get_boolean_resource(st->dpy, "broken", "Boolean");
+ if (st->broken)
+ if (! st->quiet)
+ fprintf(stderr, "-broken not available in simple mode\n");
+ } else {
+#ifndef FANCY_BUBBLES
+ st->simple = 1;
+#else /* FANCY_BUBBLES */
+ st->broken = get_boolean_resource(st->dpy, "broken", "Boolean");
+#endif /* FANCY_BUBBLES */
+ }
+}
+
+static void *
+bubbles_init (Display *dpy, Window window)
+{
+ struct state *st = (struct state *) calloc (1, sizeof(*st));
+ XGCValues gcv;
+ XWindowAttributes xgwa;
+ int i;
+
+ st->dpy = dpy;
+ st->window = window;
+
+ get_resources(st);
+
+ XGetWindowAttributes (st->dpy, st->window, &xgwa);
+
+#ifdef DEBUG
+ printf("sizof(int) on this platform is %d\n", sizeof(int));
+ printf("sizof(long) on this platform is %d\n", sizeof(long));
+#endif /* DEBUG */
+
+ st->screen_width = xgwa.width;
+ st->screen_height = xgwa.height;
+ st->screen_depth = xgwa.depth;
+
+ if (st->simple) {
+ /* These are pretty much plucked out of the air */
+ st->bubble_min_radius = (int)(0.006*(double)(MIN(st->screen_width,
+ st->screen_height)));
+ st->bubble_max_radius = (int)(0.045*(double)(MIN(st->screen_width,
+ st->screen_height)));
+ /* Some trivial values */
+ if (st->bubble_min_radius < 1)
+ st->bubble_min_radius = 1;
+ if (st->bubble_max_radius <= st->bubble_min_radius)
+ st->bubble_max_radius = st->bubble_min_radius + 1;
+
+ st->mesh_length = (2 * st->bubble_max_radius) + 3;
+
+ /* store area of each bubble of certain radius as number of 1/10s of
+ a pixel area. PI is defined in <math.h> */
+ st->bubble_areas = (long *)xmalloc((st->bubble_max_radius + 2) * sizeof(int));
+ for (i = 0; i < st->bubble_min_radius; i++)
+ st->bubble_areas[i] = 0;
+ for (i = st->bubble_min_radius; i <= (st->bubble_max_radius+1); i++)
+ st->bubble_areas[i] = calc_bubble_area(st, i);
+
+ /* Now populate the droppage values */
+ st->bubble_droppages = (int *)xmalloc((st->bubble_max_radius + 2) * sizeof(int));
+ for (i = 0; i < st->bubble_min_radius; i++)
+ st->bubble_droppages[i] = 0;
+ for (i = st->bubble_min_radius; i <= (st->bubble_max_radius+1); i++)
+ st->bubble_droppages[i] = MAX_DROPPAGE * (i - st->bubble_min_radius) / (st->bubble_max_radius - st->bubble_min_radius);
+
+ st->mesh_length = (2 * st->bubble_max_radius) + 3;
+ } else {
+#ifndef FANCY_BUBBLES
+ fprintf(stderr,
+ "Bug: simple mode code not set but FANCY_BUBBLES not defined\n");
+ exit(1);
+#else /* FANCY_BUBBLES */
+ /* Make sure all #ifdef sort of things have been taken care of in
+ get_resources(). */
+ default_to_pixmaps(st);
+
+ /* Set mesh length */
+ st->mesh_length = (2 * st->step_pixmaps[st->num_bubble_pixmaps-1]->radius) + 3;
+#endif /* FANCY_BUBBLES */
+
+ /* Am I missing something in here??? */
+ }
+
+ st->mesh_width = (st->screen_width / st->mesh_length) + 1;
+ st->mesh_height = (st->screen_height / st->mesh_length) + 1;
+ st->mesh_cells = st->mesh_width * st->mesh_height;
+ init_mesh(st);
+
+ calculate_adjacent_list(st);
+
+ adjust_areas(st);
+
+ /* Graphics contexts for simple mode */
+ if (st->simple) {
+ gcv.foreground = st->default_fg_pixel;
+ st->draw_gc = XCreateGC (st->dpy, st->window, GCForeground, &gcv);
+ gcv.foreground = st->default_bg_pixel;
+ st->erase_gc = XCreateGC (st->dpy, st->window, GCForeground, &gcv);
+ }
+
+ XClearWindow (st->dpy, st->window);
+
+# ifndef FANCY_BUBBLES
+ st->simple = True;
+# endif
+
+ return st;
+}
+
+static unsigned long
+bubbles_draw (Display *dpy, Window window, void *closure)
+{
+ struct state *st = (struct state *) closure;
+ int i;
+ for (i = 0; i < 5; i++)
+ {
+ Bubble *tmp = new_bubble(st);
+ add_to_mesh(st, tmp);
+ insert_new_bubble(st, tmp);
+ }
+ return st->delay;
+}
+
+
+static void
+bubbles_reshape (Display *dpy, Window window, void *closure,
+ unsigned int w, unsigned int h)
+{
+}
+
+static Bool
+bubbles_event (Display *dpy, Window window, void *closure, XEvent *event)
+{
+ return False;
+}
+
+static void
+bubbles_free (Display *dpy, Window window, void *closure)
+{
+ struct state *st = (struct state *) closure;
+ free (st);
+}
+
+XSCREENSAVER_MODULE ("Bubbles", bubbles)