diff options
Diffstat (limited to 'main.c')
| -rw-r--r-- | main.c | 496 |
1 files changed, 357 insertions, 139 deletions
@@ -16,6 +16,7 @@ #include <math.h> #include <png.h> #include <setjmp.h> +#include <stdarg.h> #include <stdio.h> #include <stdbool.h> #include <stdlib.h> @@ -24,21 +25,214 @@ # include <unistd.h> #endif -// Number of trailing zero bits on each color chanel, set to zero for all -// 24-bit images -#define BIT_DEPTH 24 -// Whether to sort by hue -#define HUE_SORT true +// Possible generation modes +typedef enum { + MODE_HUE_SORT, + MODE_RANDOM, +} mode_t; + +// Possible color spaces +typedef enum { + COLOR_SPACE_RGB, + COLOR_SPACE_LAB, + COLOR_SPACE_LUV, +} color_space_t; + +// Command-line options +typedef struct { + unsigned int bit_depth; + mode_t mode; + color_space_t color_space; + const char *filename; + bool help; +} options_t; + +static bool parse_options(options_t *options, int argc, char *argv[]); +static void print_usage(FILE *file, const char *command); + +// All-encompasing state struct +typedef struct { + const options_t *options; + unsigned int width; + unsigned int height; + size_t size; + uint32_t *colors; + png_byte **bitmap; +} state_t; + +static void init_state(state_t *state, const options_t *options); +static void generate_image(const state_t *state); +static void destroy_state(state_t *state); + +// Entry point +int +main(int argc, char *argv[]) +{ + options_t options; + if (!parse_options(&options, argc, argv)) { + fprintf(stderr, "\n"); + print_usage(stderr, argv[0]); + return EXIT_FAILURE; + } + + if (options.help) { + print_usage(stdout, argv[0]); + return EXIT_SUCCESS; + } + + // For consistent images + srand(0); + + state_t state; + init_state(&state, &options); + generate_image(&state); + destroy_state(&state); + return EXIT_SUCCESS; +} + +static bool +parse_arg(int argc, char *argv[], + const char *short_form, const char *long_form, + const char **value, int *i, bool *error) +{ + size_t short_len = strlen(short_form); + size_t long_len = strlen(long_form); + + const char *actual_form; + const char *arg = argv[*i]; + const char *candidate = NULL; + + if (strncmp(arg, short_form, short_len) == 0) { + actual_form = short_form; + if (strlen(arg) > short_len) { + candidate = arg + short_len; + } + } else if (strncmp(arg, long_form, long_len) == 0) { + actual_form = long_form; + if (strlen(arg) > long_len) { + if (arg[long_len] == '=') { + candidate = arg + long_len + 1; + } else { + return false; + } + } + } else { + return false; + } + + if (value) { + if (candidate) { + *value = candidate; + } else if (*i < argc - 1) { + ++*i; + *value = argv[*i]; + } else { + fprintf(stderr, "Expected a value for %s\n", arg); + *error = true; + return false; + } + } else if (candidate) { + fprintf(stderr, "Unexpected value for %s: `%s'\n", + actual_form, candidate); + *error = true; + return false; + } + + return true; +} + +static bool +str_to_uint(const char *str, unsigned int *value) +{ + char *endptr; + long result = strtol(str, &endptr, 10); + if (*str == '\0' || *endptr != '\0') { + return false; + } + if (result < 0 || result > UINT_MAX) { + return false; + } + + *value = result; + return true; +} + +static void +print_usage(FILE *file, const char *command) +{ + size_t length = strlen(command); + char whitespace[length]; + memset(whitespace, ' ', length); + + fprintf(file, "Usage:\n"); + fprintf(file, " $ %s [-b|--bit-depth DEPTH]\n", command); + fprintf(file, " %s [-s|--hue-sort] [-r|--random]\n", whitespace); + fprintf(file, " %s [-c|--color-space RGB|Lab|Luv]\n", whitespace); + fprintf(file, " %s [-o|--output PATH]\n", whitespace); + fprintf(file, " %s [-h|--help]\n", whitespace); + fprintf(file, "\n"); + fprintf(file, " -b, --bit-depth DEPTH: Use all DEPTH-bit colors (default: 24)\n"); + fprintf(file, " -s, --hue-sort: Sort colors by hue first (default)\n"); + fprintf(file, " -r, --random: Randomize colors first\n"); + fprintf(file, " -c, --color-space RGB|Lab|Luv:\n"); + fprintf(file, " Use the given color space (default: Lab)\n"); + fprintf(file, " -o, --output PATH: Output a PNG file at PATH (default: kd-forest.png)\n"); + fprintf(file, " -h, --help: Show this message\n"); +} + +static bool +parse_options(options_t *options, int argc, char *argv[]) +{ + // Set defaults + options->bit_depth = 24; + options->mode = MODE_HUE_SORT; + options->color_space = COLOR_SPACE_LAB; + options->filename = "kd-forest.png"; + options->help = false; + + bool result = true; + + for (int i = 1; i < argc; ++i) { + const char *value; + bool error = false; + + if (parse_arg(argc, argv, "-b", "--bit-depth", &value, &i, &error)) { + if (!str_to_uint(value, &options->bit_depth) + || options->bit_depth <= 0 + || options->bit_depth > 24) { + fprintf(stderr, "Invalid bit depth: `%s'\n", value); + error = true; + } + } else if (parse_arg(argc, argv, "-s", "--hue-sort", NULL, &i, &error)) { + options->mode = MODE_HUE_SORT; + } else if (parse_arg(argc, argv, "-r", "--random", NULL, &i, &error)) { + options->mode = MODE_RANDOM; + } else if (parse_arg(argc, argv, "-o", "--output", &value, &i, &error)) { + options->filename = value; + } else if (parse_arg(argc, argv, "-c", "--color-space", &value, &i, &error)) { + if (strcmp(value, "RGB") == 0) { + options->color_space = COLOR_SPACE_RGB; + } else if (strcmp(value, "Lab") == 0) { + options->color_space = COLOR_SPACE_LAB; + } else if (strcmp(value, "Luv") == 0) { + options->color_space = COLOR_SPACE_LUV; + } else { + fprintf(stderr, "Invalid color space: `%s'\n", value); + } + } else if (parse_arg(argc, argv, "-h", "--help", NULL, &i, &error)) { + options->help = true; + } else if (!error) { + fprintf(stderr, "Unexpected argument `%s'\n", argv[i]); + error = true; + } -// Which color space to use -#define USE_RGB false -#define USE_LAB true -#define USE_LUV false + if (error) { + result = false; + } + } -// Computed constants -static const unsigned int WIDTH = 1U << (BIT_DEPTH + 1)/2; // Round up -static const unsigned int HEIGHT = 1U << (BIT_DEPTH)/2; // Round down -static const unsigned int SIZE = 1U << BIT_DEPTH; + return result; +} static unsigned int rand_in(unsigned int range) @@ -52,20 +246,105 @@ rand_in(unsigned int range) return res%range; } +static uint32_t * +create_colors(const state_t *state) +{ + const unsigned int bit_depth = state->options->bit_depth; + + // From least to most perceptually important + const unsigned int bskip = 1U << (24 - bit_depth)/3; + const unsigned int rskip = 1U << (24 - bit_depth + 1)/3; + const unsigned int gskip = 1U << (24 - bit_depth + 2)/3; + + uint32_t *colors = xmalloc(state->size*sizeof(uint32_t)); + for (unsigned int b = 0, i = 0; b < 0x100; b += bskip) { + for (unsigned int g = 0; g < 0x100; g += gskip) { + for (unsigned int r = 0; r < 0x100; r += rskip, ++i) { + colors[i] = (r << 16) | (g << 8) | b; + } + } + } + + switch (state->options->mode) { + case MODE_HUE_SORT: + qsort(colors, state->size, sizeof(uint32_t), color_comparator); + break; + + case MODE_RANDOM: + // Fisher-Yates shuffle + for (unsigned int i = state->size; i-- > 0;) { + unsigned int j = rand_in(i + 1); + uint32_t temp = colors[i]; + colors[i] = colors[j]; + colors[j] = temp; + } + break; + } + + return colors; +} + +static png_byte ** +create_bitmap(const state_t *state) +{ + png_byte **rows = xmalloc(state->height*sizeof(png_byte *)); + const size_t row_size = 3*state->width*sizeof(png_byte); + for (unsigned int i = 0; i < state->height; ++i) { + rows[i] = xmalloc(row_size); + memset(rows[i], 0, row_size); + } + return rows; +} + +static void +init_state(state_t *state, const options_t *options) +{ + state->options = options; + state->width = 1U << (options->bit_depth + 1)/2; // Round up + state->height = 1U << options->bit_depth/2; // Round down + state->size = (size_t)state->width*state->height; + + printf("Generating a %u-bit, %ux%u image (%zu pixels)\n", + options->bit_depth, state->width, state->height, state->size); + + state->colors = create_colors(state); + state->bitmap = create_bitmap(state); +} + +static void generate_bitmap(const state_t *state); +static void write_png(const state_t *state, const char *filename); + +static void +generate_image(const state_t *state) +{ + generate_bitmap(state); + write_png(state, state->options->filename); +} + +static void +destroy_state(state_t *state) +{ + for (unsigned int i = 0; i < state->height; ++i) { + free(state->bitmap[i]); + } + free(state->bitmap); + free(state->colors); +} + static kd_node_t * -try_neighbor(kd_node_t *node, int dx, int dy) +try_neighbor(const state_t *state, kd_node_t *node, int dx, int dy) { if (dx < 0 && node->x < -dx) { return NULL; - } else if (dx > 0 && node->x + dx >= WIDTH) { + } else if (dx > 0 && node->x + dx >= state->width) { return NULL; } else if (dy < 0 && node->y < -dy) { return NULL; - } else if (dy > 0 && node->y + dy >= HEIGHT) { + } else if (dy > 0 && node->y + dy >= state->height) { return NULL; } - return node + (int)WIDTH*dy + dx; + return node + (int)state->width*dy + dx; } // Star pattern: @@ -84,12 +363,12 @@ static int neighbor_order[][2] = { }; static kd_node_t * -next_neighbor(kd_node_t *node) +next_neighbor(const state_t *state, kd_node_t *node) { unsigned int first = rand_in(8); for (unsigned int i = first; i < first + 8; ++i) { int *delta = neighbor_order[i%8]; - kd_node_t *neighbor = try_neighbor(node, delta[0], delta[1]); + kd_node_t *neighbor = try_neighbor(state, node, delta[0], delta[1]); if (neighbor && !neighbor->added) { return neighbor; } @@ -99,84 +378,61 @@ next_neighbor(kd_node_t *node) } static void -remove_if_surrounded(kd_forest_t *kdf, kd_node_t *node) +remove_if_surrounded(const state_t *state, kd_forest_t *kdf, kd_node_t *node) { - if (node->added && !node->removed && next_neighbor(node) == NULL) { + if (node->added && !node->removed && next_neighbor(state, node) == NULL) { kdf_remove(kdf, node); } } static void -remove_non_boundary(kd_forest_t *kdf, kd_node_t *node) +remove_non_boundary(const state_t *state, kd_forest_t *kdf, kd_node_t *node) { for (int dy = -1; dy <= 1; ++dy) { for (int dx = -1; dx <= 1; ++dx) { - kd_node_t *neighbor = try_neighbor(node, dx, dy); + kd_node_t *neighbor = try_neighbor(state, node, dx, dy); if (neighbor) { - remove_if_surrounded(kdf, neighbor); + remove_if_surrounded(state, kdf, neighbor); } } } } -static uint32_t * -create_colors(void) +static void +print_progress(const char *format, ...) { - // From least to most perceptually important - const unsigned int bskip = 1U << (24 - BIT_DEPTH)/3; - const unsigned int rskip = 1U << (24 - BIT_DEPTH + 1)/3; - const unsigned int gskip = 1U << (24 - BIT_DEPTH + 2)/3; - - uint32_t *colors = xmalloc(SIZE*sizeof(uint32_t)); - for (unsigned int b = 0, i = 0; b < 0x100; b += bskip) { - for (unsigned int g = 0; g < 0x100; g += gskip) { - for (unsigned int r = 0; r < 0x100; r += rskip, ++i) { - colors[i] = (r << 16) | (g << 8) | b; - } - } - } - - if (HUE_SORT) { - qsort(colors, SIZE, sizeof(uint32_t), color_comparator); - } else { - // Fisher-Yates shuffle - for (unsigned int i = SIZE; i-- > 0;) { - unsigned int j = rand_in(i + 1); - uint32_t temp = colors[i]; - colors[i] = colors[j]; - colors[j] = temp; - } +#if __unix__ + static bool tty_checked = false; + static bool tty = false; + if (!tty_checked) { + tty = isatty(STDOUT_FILENO); + tty_checked = true; } + const char *clear_line = tty ? "\033[2K\r" : ""; + const char *new_line = tty ? "" : "\n"; +#else + const char *clear_line = ""; + const char *new_line = "\n"; +#endif - return colors; -} + printf("%s", clear_line); -static kd_node_t * -create_kd_nodes(void) -{ - return xmalloc(SIZE*sizeof(kd_node_t)); -} + va_list args; + va_start(args, format); + vprintf(format, args); + va_end(args); -static png_byte ** -create_bitmap(void) -{ - png_byte **rows = xmalloc(HEIGHT*sizeof(png_byte *)); - const size_t row_size = 3*WIDTH*sizeof(png_byte); - for (unsigned int i = 0; i < HEIGHT; ++i) { - rows[i] = xmalloc(row_size); - memset(rows[i], 0, row_size); - } - return rows; + printf("%s", new_line); + fflush(stdout); } static void -generate_image(const uint32_t *colors, kd_node_t *nodes, - unsigned int initial_x, unsigned int initial_y, - png_byte **bitmap) +generate_bitmap(const state_t *state) { - for (unsigned int y = 0, i = 0; y < HEIGHT; ++y) { - for (unsigned int x = 0; x < WIDTH; ++x, ++i) { - kd_node_init(nodes + y*WIDTH + x, x, y); + kd_node_t *nodes = xmalloc(state->size*sizeof(kd_node_t)); + for (unsigned int y = 0, i = 0; y < state->height; ++y) { + for (unsigned int x = 0; x < state->width; ++x, ++i) { + kd_node_init(nodes + y*state->width + x, x, y); } } @@ -184,71 +440,65 @@ generate_image(const uint32_t *colors, kd_node_t *nodes, kd_forest_t kdf; kdf_init(&kdf); -#if __unix__ - bool tty = isatty(1); - const char *clear_line = tty ? "\033[2K\r" : ""; - const char *new_line = tty ? "" : "\n"; -#else - const char *clear_line = ""; - const char *new_line = "\n"; -#endif - size_t max_size = 0; // Do multiple passes to get rid of artifacts in HUE_SORT mode - for (unsigned int i = 1, progress = 0; i <= BIT_DEPTH; ++i) { + unsigned int bit_depth = state->options->bit_depth; + for (unsigned int i = 1, progress = 0; i <= bit_depth; ++i) { unsigned int stripe = 1 << i; - for (unsigned int j = stripe/2 - 1; j < SIZE; j += stripe, ++progress) { - if (progress%WIDTH == 0) { - printf("%s%.2f%%\t| boundary size: %zu\t| max boundary size: %zu%s", - clear_line, 100.0*progress/SIZE, kdf.size, max_size, new_line); - fflush(stdout); + for (unsigned int j = stripe/2 - 1; j < state->size; j += stripe, ++progress) { + if (progress%state->width == 0) { + print_progress("%.2f%%\t| boundary size: %zu\t| max boundary size: %zu", + 100.0*progress/state->size, kdf.size, max_size); } - uint32_t color = colors[j]; + uint32_t color = state->colors[j]; kd_node_t target; -#if USE_RGB - color_set_RGB(target.coords, color); -#elif USE_LAB - color_set_Lab(target.coords, color); -#elif USE_LUV - color_set_Luv(target.coords, color); -#else -# error "Pick one!" -#endif + switch (state->options->color_space) { + case COLOR_SPACE_RGB: + color_set_RGB(target.coords, color); + break; + case COLOR_SPACE_LAB: + color_set_Lab(target.coords, color); + break; + case COLOR_SPACE_LUV: + color_set_Luv(target.coords, color); + break; + } kd_node_t *new_node; if (j == 0) { // First node goes in the center - new_node = nodes + WIDTH*initial_y + initial_x; + new_node = nodes + state->size/2 + state->width/2; } else { kd_node_t *nearest = kdf_find_nearest(&kdf, &target); - new_node = next_neighbor(nearest); + new_node = next_neighbor(state, nearest); } memcpy(new_node->coords, target.coords, sizeof(target.coords)); kdf_insert(&kdf, new_node); - remove_non_boundary(&kdf, new_node); + remove_non_boundary(state, &kdf, new_node); if (kdf.size > max_size) { max_size = kdf.size; } - png_byte *pixel = bitmap[new_node->y] + 3*new_node->x; + png_byte *pixel = state->bitmap[new_node->y] + 3*new_node->x; color_unpack(pixel, color); } } - printf("%s%.2f%%\t| boundary size: 0\t| max boundary size: %zu\n", - clear_line, 100.0, max_size); + print_progress("%.2f%%\t| boundary size: 0\t| max boundary size: %zu\n", + 100.0, max_size); kdf_destroy(&kdf); + free(nodes); } static void -write_png(const char *filename, png_byte **bitmap) +write_png(const state_t *state, const char *filename) { FILE *file = fopen(filename, "wb"); if (!file) { @@ -272,44 +522,12 @@ write_png(const char *filename, png_byte **bitmap) } png_init_io(png_ptr, file); - png_set_IHDR(png_ptr, info_ptr, WIDTH, HEIGHT, 8, + png_set_IHDR(png_ptr, info_ptr, state->width, state->height, 8, PNG_COLOR_TYPE_RGB, PNG_INTERLACE_ADAM7, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT); png_set_sRGB_gAMA_and_cHRM(png_ptr, info_ptr, PNG_sRGB_INTENT_ABSOLUTE); - png_set_rows(png_ptr, info_ptr, bitmap); + png_set_rows(png_ptr, info_ptr, state->bitmap); png_write_png(png_ptr, info_ptr, PNG_TRANSFORM_IDENTITY, NULL); png_destroy_write_struct(&png_ptr, &info_ptr); fclose(file); } - -int -main(void) -{ - printf("Generating a %ux%u image (%u pixels)\n", WIDTH, HEIGHT, SIZE); - - // For consistent images - srand(0); - - // Generate all the colors - uint32_t *colors = create_colors(); - // Make a pool of potential k-d nodes - kd_node_t *nodes = create_kd_nodes(); - - // Allocate the bitmap - png_byte **bitmap = create_bitmap(); - - // Generate the image - generate_image(colors, nodes, WIDTH/2, HEIGHT/2, bitmap); - - // Write out the image - write_png("kd-forest.png", bitmap); - - // Clean up - for (unsigned int i = 0; i < HEIGHT; ++i) { - free(bitmap[i]); - } - free(bitmap); - free(nodes); - free(colors); - return 0; -} |