X-Git-Url: http://git.subgeniuskitty.com/screensavers/.git/blobdiff_plain/80cfe219638914799dd0f4aef4a2840c20cf04ee..20848f707109f41eb39afbd2cdb3147a286c7dbe:/hacks/WolframAutomata/WolframAutomata.c diff --git a/hacks/WolframAutomata/WolframAutomata.c b/hacks/WolframAutomata/WolframAutomata.c index 33182e1..c788f01 100644 --- a/hacks/WolframAutomata/WolframAutomata.c +++ b/hacks/WolframAutomata/WolframAutomata.c @@ -10,36 +10,67 @@ /* TODO: I suppose a lot of this stuff goes in the README instead. */ /* TODO: Explain the data structures in detail. */ /* TODO: Explain all the options, like the various starting conditions. */ +/* TODO: Explain all the dependencies like libXpm. */ +/* TODO: Explain that the program is inherently double-buffered but if you don't have VSync turned on, all those alternating lines are going to look terrible when they scroll upward. */ - +/* TODO: Add a #define for the hack version. */ /* TODO: Check manpage for all functions I use and ensure my includes are correct. I don't want to depend on picking up includes via screenhack.h. */ /* TODO: Verify everything in this file is C89. Get rid of things like '//' comments, pack all my declarations upfront, no stdint, etc. */ +#include #include "screenhack.h" +/* + * We do a few manual manipulations of X resources in this hack, like picking + * random colors. In order to ensure our manual manipulations always use the + * same X resource specification as Xscreensaver, we pass HACKNAME to + * Xscreensaver via the XSCREENSAVER_MODULE() line at the bottom of this file, + * and then always use HACKNAME or MAKE_STRING(HACKNAME) as the base of the + * resource specification when making manual manipulations. + */ +#define HACKNAME WolframAutomata +#define MAKE_STRING_X(s) #s +#define MAKE_STRING(s) MAKE_STRING_X(s) + // Command line options // directory to output XBM files of each run (and call an external command to convert to PNGs?) // -save-dir STRING +// (could use libXpm to save an XPM and then convert to PNG with ImageMagick) (this is a single function call to go from pixmap -> file) +// (since it depends on an external library, make this whole feature optional at build-time?) // number of generations to simulate +// -random-generations // -num-generations N // delay time (speed of simulation) +// -random-delay // -delay-usec N // foreground and background color -// ??? (strings of some sort, but I need to look up what X resources to interact with) +// -random-colors (highest precedence) +// -foreground "COLORNAME" +// -background "COLORNAME" +// (default is black and white) +// (mention sample color combinations in manpage, and link to: https://en.wikipedia.org/wiki/X11_color_names) +// (note to the user that most color names they can naturally think of (e.g. red, purple, gray, pink, etc) are valid X11 color names for these CLI options.) // display info overlay with CA number and start conditions? // -overlay // which ruleset number to use? Or random? Or random from small set of hand-selected interesting examples? // In order of precedence: -// -random (select a random rule on each run) +// -rule-random (select a random rule on each run) // -rule N (always simulate Rule N on each run) // (if neither of the above two are specified, then a random CURATED rule is selected on each run) -// which starting population to use? Or random? Or one bit in middle? Or one bit on edge? (For random: Can I allow specifying a density like 25%, 50%, 75%?) -// Options (with precedence): -population STRING (string is a comma separated list of cell IDs to populate, starting from 0) -// -population-curated -// -population-random +// which starting population to use, random or one bit? (for random: allow specifying a density) +// In order of precedence: +// -population-single +// -population-random DENSITY +// (the two options above only apply to the simulation under the -rule-random or -rule N options. in curated mode, starting population is defined in the curation array) +// TODO: In the future, add the option for user to pass list of cell IDs to turn ON. // size of pixel square (e.g. 1x1, 2x2, 3x3, etc) +// -random-pixel-size // -pixel-size N +/* -------------------------------------------------------------------------- */ +/* Data Structures */ +/* -------------------------------------------------------------------------- */ + struct state { /* Various X resources */ Display * dpy; @@ -61,6 +92,10 @@ struct state { uint8_t rule_requested; // Note: Repurposing Rule 0 as a null value. Bool rule_random; + // TODO: Describe these. + int population_density; + Bool population_single; + /* Misc Commandline Options */ int pixel_size; /* Size of CA cell in pixels (e.g. pixel_size=3 means 3x3 pixels per cell). */ int delay_microsec; /* Requested delay to screenhack framework before next call to WolframAutomata_draw(). */ @@ -70,22 +105,195 @@ struct state { size_t number_of_cells; }; -// TODO: Check the full set of 256 CAs for visually interesting examples. -static const uint8_t curated_rule_list[] = { - 22, - 30, - 45, - 57, - 73, - 86 +// TODO: Decorations +enum seed_population { + random_cell, + middle_cell, + edge_cell +}; + +// TODO: Decorations +struct curated_ruleset { + uint8_t rule; + enum seed_population seed; +}; + +// TODO: Decorations +static const struct curated_ruleset curated_ruleset_list[] = { + {18, middle_cell}, + {30, middle_cell}, + {45, middle_cell}, + {54, middle_cell}, + {57, middle_cell}, + {73, middle_cell}, + {105, middle_cell}, + {109, middle_cell}, + {129, middle_cell}, + {133, middle_cell}, + {135, middle_cell}, + {150, middle_cell}, + {30, edge_cell}, + {45, edge_cell}, + {57, edge_cell}, + {60, edge_cell}, + {75, edge_cell}, + {107, edge_cell}, + {110, edge_cell}, + {133, edge_cell}, + {137, edge_cell}, + {169, edge_cell}, + {225, edge_cell}, + {22, random_cell}, + {30, random_cell}, + {54, random_cell}, + {62, random_cell}, + {90, random_cell}, + {105, random_cell}, + {108, random_cell}, + {110, random_cell}, + {126, random_cell}, + {146, random_cell}, + {150, random_cell}, + {182, random_cell}, + {184, random_cell}, + {225, random_cell}, + {240, random_cell} +}; + +// TODO: Decorations +struct color_pair { + char * fg; + char * bg; +}; + +// TODO: Decorations +static const struct color_pair color_list[] = { + {"red", "black"}, + {"olive", "black"}, + {"teal", "black"}, + {"slateblue", "black"}, + {"violet", "black"}, + {"purple", "black"}, + {"white", "black"}, + {"white", "darkgreen"}, + {"white", "darkmagenta"}, + {"white", "darkred"}, + {"white", "darkblue"}, + {"darkslategray", "darkslategray1"}, + {"lightsteelblue", "darkslategray"}, + {"royalblue4", "royalblue"}, + {"antiquewhite2", "antiquewhite4"}, + {"darkolivegreen1", "darkolivegreen"}, + {"darkseagreen1", "darkseagreen4"}, + {"pink", "darkred"}, + {"lightblue", "darkgreen"}, + {"red", "blue"}, + {"red", "darkgreen"}, + {"aqua", "teal"}, + {"darkblue", "teal"}, + {"khaki", "seagreen"}, + {"khaki", "darkolivegreen"}, + {"lightslategray", "darkslategray"}, + {"tomato", "darkslategray"}, + {"tomato", "darkcyan"} }; +/* -------------------------------------------------------------------------- */ +/* Helper Functions */ +/* -------------------------------------------------------------------------- */ + +// TODO: decorations? inline? +void +generate_random_seed(struct state * state) +{ + int i; + for (i = 0; i < state->number_of_cells; i++) { + state->current_generation[i] = ((random() % 100) < state->population_density) ? True : False; + } +} + +// TODO: function decorations? +// TODO: Explain why this santizes the index for accessing current_generation (i.e. it creates a circular topology). +size_t +sindex(struct state * state, int index) +{ + while (index < 0) { + index += state->number_of_cells; + } + while (index >= state->number_of_cells) { + index -= state->number_of_cells; + } + return (size_t) index; +} + +// TODO: function decorations? +// TODO: At least give a one-sentence explanation of the algorithm since this function is the core of the simulation. +Bool +calculate_cell(struct state * state, int cell_id) +{ + uint8_t cell_pattern = 0; + int i; + for (i = -1; i < 2; i++) { + cell_pattern = cell_pattern << 1; + if (state->current_generation[sindex(state, cell_id+i)] == True) { + cell_pattern |= 1; + } + } + if ((state->rule_number >> cell_pattern) & 1) { + return True; + } else { + return False; + } +} + +// TODO: function decorations? +void +render_current_generation(struct state * state) +{ + size_t xpos; + for (xpos = 0; xpos < state->number_of_cells; xpos++) { + if (state->current_generation[xpos] == True) { + XFillRectangle(state->dpy, state->evolution_history, state->gc, xpos*state->pixel_size, state->ypos, state->pixel_size, state->pixel_size); + } else { + XSetForeground(state->dpy, state->gc, state->bg); + XFillRectangle(state->dpy, state->evolution_history, state->gc, xpos*state->pixel_size, state->ypos, state->pixel_size, state->pixel_size); + XSetForeground(state->dpy, state->gc, state->fg); + } + } +} + +/* -------------------------------------------------------------------------- */ +/* Screenhack API Functions */ +/* -------------------------------------------------------------------------- */ + +static Bool +WolframAutomata_event(Display * dpy, Window win, void * closure, XEvent * event) +{ + return False; +} + +static void +WolframAutomata_free(Display * dpy, Window win, void * closure) +{ + struct state * state = closure; + XFreeGC(state->dpy, state->gc); + XFreePixmap(state->dpy, state->evolution_history); + free(state->current_generation); + free(state); +} + static void * WolframAutomata_init(Display * dpy, Window win) { - struct state * state = calloc(1, sizeof(*state)); // TODO: Check calloc() call + struct state * state = calloc(1, sizeof(*state)); + if (!state) { + fprintf(stderr, "ERROR: Failed to calloc() for state struct in WolframAutomata_init().\n"); + exit(EXIT_FAILURE); + } + XGCValues gcv; XWindowAttributes xgwa; + const struct curated_ruleset * curated_ruleset = NULL; state->dpy = dpy; state->win = win; @@ -95,25 +303,94 @@ WolframAutomata_init(Display * dpy, Window win) state->ylim = xgwa.height; state->ypos = 0; // TODO: Explain why. + if (get_boolean_resource(state->dpy, "random-colors", "Boolean")) { + XrmDatabase db = XtDatabase(state->dpy); + size_t rand_i = random() % sizeof(color_list)/sizeof(color_list[0]); + XrmPutStringResource(&db, MAKE_STRING(HACKNAME) ".background", color_list[rand_i].bg); + XrmPutStringResource(&db, MAKE_STRING(HACKNAME) ".foreground", color_list[rand_i].fg); + } + state->fg = gcv.foreground = get_pixel_resource(state->dpy, xgwa.colormap, "foreground", "Foreground"); state->bg = gcv.background = get_pixel_resource(state->dpy, xgwa.colormap, "background", "Background"); state->gc = XCreateGC(state->dpy, state->win, GCForeground, &gcv); - state->delay_microsec = get_integer_resource(state->dpy, "delay-usec", "Integer"); - if (state->delay_microsec < 0) state->delay_microsec = 0; - - state->pixel_size = get_integer_resource(state->dpy, "pixel-size", "Integer"); + /* Set the size of each simulated cell as NxN pixels for pixel_size=N. */ + if (get_boolean_resource(state->dpy, "random-pixel-size", "Boolean")) { + /* Although we are choosing the pixel size 'randomly', a truly random */ + /* selection would bias toward large numbers since there are more of */ + /* them. To avoid this, we select a random number for a bit shift, */ + /* resulting in a pixel size of 1, 2, 4, 8, 16 or 32, equally likely. */ + state->pixel_size = 1 << (random() % 6); + } else { + state->pixel_size = get_integer_resource(state->dpy, "pixel-size", "Integer"); + } if (state->pixel_size < 1) state->pixel_size = 1; if (state->pixel_size > state->xlim) state->pixel_size = state->xlim; state->number_of_cells = state->xlim / state->pixel_size; + // TODO: Do we want to enforce that number_of_cells > 0? + + /* Set the delay (in microseconds) between simulation of each generation */ + /* of the simulation, also known as the delay between calls to */ + /* WolframAutomata_draw(), which simulates one generation per call. */ + if (get_boolean_resource(state->dpy, "random-delay", "Boolean")) { + /* When randomly setting the delay, the problem is to avoid being too */ + /* fast or too slow, as well as ensuring slower speeds are chosen */ + /* with the same likelihood as faster speeds, as perceived by a */ + /* human. By empirical observation, we note that for 1x1 up to 4x4 */ + /* pixel cell sizes, values for state->delay_microsec between */ + /* 2048 (2^11) and 16556 (2^14) produce pleasant scroll rates. To */ + /* maintain this appearance, we bitshift state->pixel_size down until */ + /* it is a maximum of 4x4 pixels in size, record how many bitshifts */ + /* took place, and then shift our valid window for */ + /* state->delay_microsec up by an equal number of bitshifts. For */ + /* example, if state->pixel_size=9, then it takes one right shift to */ + /* reach state->pixel_size=4. Thus, the valid window for */ + /* state->delay_microsec becomes 4096 (2^12) up to 32768 (2^15). */ + size_t pixel_shift_range = 1; + size_t pixel_size_temp = state->pixel_size; + while (pixel_size_temp > 4) { + pixel_size_temp >>= 1; + pixel_shift_range++; + } + /* In the below line, '3' represents the total range, namely '14-11' */ + /* from '2^14' and '2^11' as the endpoints. Similarly, the '11' in */ + /* the below line represents the starting point of this range, from */ + /* the exponent in '2^11'. */ + state->delay_microsec = 1 << ((random() % 3) + 11 + pixel_shift_range); + } else { + state->delay_microsec = get_integer_resource(state->dpy, "delay-usec", "Integer"); + } + if (state->delay_microsec < 0) state->delay_microsec = 0; + /* Set the number of generations to simulate before wiping the simulation */ + /* and re-running with new settings. */ + if (get_boolean_resource(state->dpy, "random-num-generations", "Boolean")) { + /* By empirical observation, keep the product */ + /* state->num_generations * state->pixel_size */ + /* below 10,000 to avoid BadAlloc errors from the X server due to */ + /* requesting an enormous pixmap. This value works on both a 12 core */ + /* Xeon with 108 GiB of RAM and a Sun Ultra 2 with 2 GiB of RAM. */ + state->num_generations = random() % (10000 / state->pixel_size); + /* Ensure selected value is large enough to at least fill the screen. */ + /* Cast to avoid overflow. */ + if ((long)state->num_generations * (long)state->pixel_size < state->ylim) { + state->num_generations = (state->ylim / state->pixel_size) + 1; + } + } else { + state->num_generations = get_integer_resource(state->dpy, "num-generations", "Integer"); + } /* The minimum number of generations is 2 since we must allocate enough */ /* space to hold the seed generation and at least one pass through */ /* WolframAutomata_draw(), which is where we check whether or not we've */ /* reached the end of the pixmap. */ - state->num_generations = get_integer_resource(state->dpy, "num-generations", "Integer"); if (state->num_generations < 0) state->num_generations = 2; + /* The maximum number of generations is pixel_size dependent. This is a */ + /* soft limit and may be increased if you have plenty of RAM (and a */ + /* cooperative X server). The value 10,000 was determined empirically. */ + if ((long)state->num_generations * (long)state->pixel_size > 10000) { + state->num_generations = 10000 / state->pixel_size; + } /* Time to figure out which rule to use for this simulation. */ /* We ignore any weirdness resulting from the following cast since every */ @@ -134,75 +411,57 @@ WolframAutomata_init(Display * dpy, Window win) } else { /* No command-line options were specified, so select rules randomly */ /* from a curated list. */ - size_t number_of_array_elements = sizeof(curated_rule_list)/sizeof(curated_rule_list[0]); - state->rule_number = curated_rule_list[random() % number_of_array_elements]; + size_t number_of_array_elements = sizeof(curated_ruleset_list)/sizeof(curated_ruleset_list[0]); + curated_ruleset = &curated_ruleset_list[random() % number_of_array_elements]; + state->rule_number = curated_ruleset->rule; + } + + /* Time to construct the seed generation for this simulation. */ + state->population_single = get_boolean_resource(state->dpy, "population-single", "Boolean"); + state->population_density = get_integer_resource(state->dpy, "population-density", "Integer"); + if (state->population_density < 0 || state->population_density > 100) state->population_density = 50; + state->current_generation = calloc(1, sizeof(*state->current_generation)*state->number_of_cells); + if (!state->current_generation) { + fprintf(stderr, "ERROR: Failed to calloc() for cell generation in WolframAutomata_init().\n"); + exit(EXIT_FAILURE); + } + if (curated_ruleset) { + /* If we're using a curated ruleset, ignore any CLI flags related to */ + /* setting the seed generation, instead drawing that information from */ + /* the curated ruleset. */ + switch (curated_ruleset->seed) { + case random_cell: generate_random_seed(state); break; + case middle_cell: state->current_generation[state->number_of_cells/2] = True; break; + case edge_cell : state->current_generation[0] = True; break; + } + } else { + /* If we're not using a curated ruleset, process any relevant flags */ + /* from the user, falling back to a random seed generation if nothing */ + /* else is specified. */ + if (state->population_single) { + state->current_generation[0] = True; + } else { + generate_random_seed(state); + } } // TODO: These should be command-line options, but I need to learn how the get_integer_resource() and similar functions work first. state->display_info = True; - state->current_generation = calloc(1, (sizeof(*(state->current_generation))*state->number_of_cells)); // TODO: Check calloc() call TODO: Can't recall precedence; can I eliminate any parenthesis? - // TODO: Make the starting state a user-configurable option. At least give the user some options like 'random', 'one-middle', 'one edge', etc. - // Ideally accept something like a list of integers representing starting pixels to be "on". - state->current_generation[0] = True; - state->evolution_history = XCreatePixmap(state->dpy, state->win, state->xlim, state->num_generations*state->pixel_size, xgwa.depth); // Pixmap contents are undefined after creation. Explicitly set a black // background by drawing a black rectangle over the entire pixmap. - XSetForeground(state->dpy, state->gc, state->bg); + XColor blackx, blacks; + XAllocNamedColor(state->dpy, DefaultColormapOfScreen(DefaultScreenOfDisplay(state->dpy)), "black", &blacks, &blackx); + XSetForeground(state->dpy, state->gc, blacks.pixel); XFillRectangle(state->dpy, state->evolution_history, state->gc, 0, 0, state->xlim, state->num_generations*state->pixel_size); XSetForeground(state->dpy, state->gc, state->fg); - // TODO: Need to draw starting generation on pixmap and increment state->ypos. + render_current_generation(state); + state->ypos += state->pixel_size; return state; } -// TODO: function decorations? -// TODO: Explain why this santizes the index for accessing current_generation (i.e. it creates a circular topology). -size_t -sindex(struct state * state, int index) -{ - while (index < 0) { - index += state->number_of_cells; - } - while (index >= state->number_of_cells) { - index -= state->number_of_cells; - } - return (size_t) index; -} - -// TODO: function decorations? -// TODO: At least give a one-sentence explanation of the algorithm since this function is the core of the simulation. -Bool -calculate_cell(struct state * state, int cell_id) -{ - uint8_t cell_pattern = 0; - int i; - for (i = -1; i < 2; i++) { - cell_pattern = cell_pattern << 1; - if (state->current_generation[sindex(state, cell_id+i)] == True) { - cell_pattern |= 1; - } - } - if ((state->rule_number >> cell_pattern) & 1) { - return True; - } else { - return False; - } -} - -// TODO: function decorations? -void -render_current_generation(struct state * state) -{ - size_t xpos; - for (xpos = 0; xpos < state->number_of_cells; xpos++) { - if (state->current_generation[xpos] == True) { - XFillRectangle(state->dpy, state->evolution_history, state->gc, xpos*state->pixel_size, state->ypos, state->pixel_size, state->pixel_size); - } - } -} - static unsigned long WolframAutomata_draw(Display * dpy, Window win, void * closure) { @@ -235,8 +494,8 @@ WolframAutomata_draw(Display * dpy, Window win, void * closure) } else { // TODO: Wait for a second or two, clear the screen and do a new iteration with suitably changed settings. // Note: Since we can't actually loop or sleep here, we need to add a flag to the state struct to indicate that we're in an 'admiration timewindow' (and indicate when it should end) - printf("infinite hamster wheel\n"); - while (1) continue; + WolframAutomata_free(dpy, win, state); + closure = WolframAutomata_init(dpy, win); } // Calculate the vertical offset of the current 'window' into the history @@ -259,41 +518,40 @@ WolframAutomata_draw(Display * dpy, Window win, void * closure) static const char * WolframAutomata_defaults[] = { ".background: black", ".foreground: white", + "*random-colors: False", "*delay-usec: 25000", // TODO: Difference between dot and asterisk? Presumably the asterisk matches all resouces of attribute "pixelsize"? Apply answer to all new options. "*pixel-size: 2", "*num-generations: 5000", "*rule-requested: 0", "*rule-random: False", + "*population-density: 50", + "*population-single: False", + "*random-delay: False", + "*random-pixel-size: False", + "*random-num-generations: False", 0 }; // TODO: Fix formatting static XrmOptionDescRec WolframAutomata_options[] = { + { "-background", ".background", XrmoptionSepArg, 0}, + { "-foreground", ".foreground", XrmoptionSepArg, 0}, + { "-random-colors", ".random-colors", XrmoptionNoArg, "True"}, { "-delay-usec", ".delay-usec", XrmoptionSepArg, 0 }, { "-pixel-size", ".pixel-size", XrmoptionSepArg, 0 }, { "-num-generations", ".num-generations", XrmoptionSepArg, 0 }, { "-rule", ".rule-requested", XrmoptionSepArg, 0 }, { "-rule-random", ".rule-random", XrmoptionNoArg, "True" }, + { "-population-density", ".population-density", XrmoptionSepArg, 0 }, + { "-population-single", ".population-single", XrmoptionNoArg, "True" }, + { "-random-delay", ".random-delay", XrmoptionNoArg, "True" }, + { "-random-pixel-size", ".random-pixel-size", XrmoptionNoArg, "True" }, + { "-random-num-generations", ".random-num-generations", XrmoptionNoArg, "True" }, + { 0, 0, 0, 0 } }; -static Bool -WolframAutomata_event(Display * dpy, Window win, void * closure, XEvent * event) -{ - return False; -} - -static void -WolframAutomata_free(Display * dpy, Window win, void * closure) -{ - struct state * state = closure; - XFreeGC(state->dpy, state->gc); - XFreePixmap(state->dpy, state->evolution_history); - free(state->current_generation); - free(state); -} - static void WolframAutomata_reshape(Display * dpy, Window win, void * closure, unsigned int w, unsigned int h) { @@ -301,5 +559,5 @@ WolframAutomata_reshape(Display * dpy, Window win, void * closure, unsigned int closure = WolframAutomata_init(dpy, win); } -XSCREENSAVER_MODULE ("1D Nearest-Neighbor Cellular Automata", WolframAutomata) +XSCREENSAVER_MODULE ("1D Nearest-Neighbor Cellular Automata", HACKNAME)