summaryrefslogtreecommitdiffstats
path: root/main.c
blob: d25551598e07f6cdab3238079ac559814e198d8c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
/*********************************************************************
 * kd-forest                                                         *
 * Copyright (C) 2014 Tavian Barnes <tavianator@tavianator.com>      *
 *                                                                   *
 * This program is free software. It comes without any warranty, to  *
 * the extent permitted by applicable law. You can redistribute it   *
 * and/or modify it under the terms of the Do What The Fuck You Want *
 * To Public License, Version 2, as published by Sam Hocevar. See    *
 * the COPYING file or http://www.wtfpl.net/ for more details.       *
 *********************************************************************/

#include "color.h"
#include "kd-forest.h"
#include "options.h"
#include "util.h"
#include <math.h>
#include <png.h>
#include <setjmp.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#if __unix__
#  include <unistd.h>
#endif

// A single pixel in all its glory
typedef struct {
  double value[KD_DIMEN];
  kd_node_t *node;
  unsigned int x, y;
  bool filled;
} pixel_t;

// All-encompasing state struct
typedef struct {
  const options_t *options;
  unsigned int width;
  unsigned int height;
  size_t size;
  uint32_t *colors;
  pixel_t *pixels;
  png_byte **bitmap;
} state_t;

static void init_state(state_t *state, const options_t *options);
static void generate_image(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;
  }

  state_t state;
  init_state(&state, &options);
  generate_image(&state);
  destroy_state(&state);
  return EXIT_SUCCESS;
}

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 = xrand(i + 1);
      uint32_t temp = colors[i];
      colors[i] = colors[j];
      colors[j] = temp;
    }
    break;
  }

  return colors;
}

static pixel_t *
create_pixels(const state_t *state)
{
  pixel_t *pixels = xmalloc(state->size*sizeof(pixel_t));
  for (unsigned int y = 0, i = 0; y < state->height; ++y) {
    for (unsigned int x = 0; x < state->width; ++x, ++i) {
      pixel_t *pixel = pixels + i;
      pixel->node = NULL;
      pixel->x = x;
      pixel->y = y;
      pixel->filled = false;
    }
  }
  return pixels;
}

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)
{
  xsrand(options->seed);

  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->pixels = create_pixels(state);
  state->bitmap = create_bitmap(state);
}

static void generate_bitmap(state_t *state);
static void write_png(const state_t *state, const char *filename);

static void
generate_image(state_t *state)
{
  generate_bitmap(state);

  if (!state->options->animate) {
    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->pixels);
  free(state->colors);
}

static pixel_t *
get_pixel(const state_t *state, unsigned int x, unsigned int y)
{
  return state->pixels + state->width*y + x;
}

static pixel_t *
try_neighbor(const state_t *state, pixel_t *pixel, int dx, int dy)
{
  if (dx < 0 && pixel->x < -dx) {
    return NULL;
  } else if (dx > 0 && pixel->x + dx >= state->width) {
    return NULL;
  } else if (dy < 0 && pixel->y < -dy) {
    return NULL;
  } else if (dy > 0 && pixel->y + dy >= state->height) {
    return NULL;
  }

  return pixel + (int)state->width*dy + dx;
}

static unsigned int
get_all_neighbors(const state_t *state, pixel_t *pixel, pixel_t *neighbors[8])
{
  unsigned int size = 0;

  for (int dy = -1; dy <= 1; ++dy) {
    for (int dx = -1; dx <= 1; ++dx) {
      if (dx == 0 && dy == 0) {
        continue;
      }

      pixel_t *neighbor = try_neighbor(state, pixel, dx, dy);
      if (neighbor) {
        neighbors[size++] = neighbor;
      }
    }
  }

  return size;
}

static unsigned int
get_neighbors(const state_t *state, pixel_t *pixel, pixel_t *neighbors[8], bool filled)
{
  unsigned int size = 0;

  for (int dy = -1; dy <= 1; ++dy) {
    for (int dx = -1; dx <= 1; ++dx) {
      if (dx == 0 && dy == 0) {
        continue;
      }

      pixel_t *neighbor = try_neighbor(state, pixel, dx, dy);
      if (neighbor && neighbor->filled == filled) {
        neighbors[size++] = neighbor;
      }
    }
  }

  return size;
}

static pixel_t *
select_empty_neighbor(const state_t *state, pixel_t *pixel)
{
  pixel_t *neighbors[8];
  unsigned int size = get_neighbors(state, pixel, neighbors, false);
  return neighbors[xrand(size)];
}

static pixel_t *
find_next_pixel(const state_t *state, const kd_forest_t *kdf, const double target[KD_DIMEN])
{
  kd_node_t *nearest = kdf_find_nearest(kdf, target);
  pixel_t *pixel = get_pixel(state, nearest->x, nearest->y);

  if (state->options->selection == SELECTION_MIN) {
    pixel = select_empty_neighbor(state, pixel);
  }

  return pixel;
}

static void
ensure_pixel_removed(kd_forest_t *kdf, pixel_t *pixel)
{
  if (pixel->node) {
    kdf_remove(kdf, pixel->node);
    pixel->node = NULL;
  }
}

static bool
has_empty_neighbors(const state_t *state, pixel_t *pixel)
{
  for (int dy = -1; dy <= 1; ++dy) {
    for (int dx = -1; dx <= 1; ++dx) {
      if (dx == 0 && dy == 0) {
        continue;
      }

      pixel_t *neighbor = try_neighbor(state, pixel, dx, dy);
      if (neighbor && !neighbor->filled) {
        return true;
      }
    }
  }

  return false;
}

static void
insert_new_pixel_min(state_t *state, kd_forest_t *kdf, pixel_t *pixel)
{
  pixel->filled = true;

  if (has_empty_neighbors(state, pixel)) {
    pixel->node = new_kd_node(pixel->value, pixel->x, pixel->y);
    kdf_insert(kdf, pixel->node);
  }

  pixel_t *neighbors[8];
  unsigned int size = get_all_neighbors(state, pixel, neighbors);
  for (unsigned int i = 0; i < size; ++i) {
    pixel_t *neighbor = neighbors[i];
    if (!has_empty_neighbors(state, neighbor)) {
      ensure_pixel_removed(kdf, neighbor);
    }
  }
}

static void
insert_new_pixel_mean(state_t *state, kd_forest_t *kdf, pixel_t *pixel)
{
  pixel->filled = true;
  ensure_pixel_removed(kdf, pixel);

  pixel_t *neighbors[8];
  unsigned int size = get_neighbors(state, pixel, neighbors, false);
  for (unsigned int i = 0; i < size; ++i) {
    pixel_t *neighbor = neighbors[i];

    double value[KD_DIMEN] = { 0.0 };

    pixel_t *filled[8];
    unsigned int nfilled = get_neighbors(state, neighbor, filled, true);
    for (unsigned int j = 0; j < nfilled; ++j) {
      for (unsigned int k = 0; k < KD_DIMEN; ++k) {
        value[k] += filled[j]->value[k];
      }
    }

    for (unsigned int j = 0; j < KD_DIMEN; ++j) {
      value[j] /= nfilled;
    }

    ensure_pixel_removed(kdf, neighbor);
    neighbor->node = new_kd_node(value, neighbor->x, neighbor->y);
    kdf_insert(kdf, neighbor->node);
  }
}

static void
insert_new_pixel(state_t *state, kd_forest_t *kdf, pixel_t *pixel)
{
  switch (state->options->selection) {
  case SELECTION_MIN:
    insert_new_pixel_min(state, kdf, pixel);
    break;

  case SELECTION_MEAN:
    insert_new_pixel_mean(state, kdf, pixel);
    break;
  }
}

static void
print_progress(const char *format, ...)
{
#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

  printf("%s", clear_line);

  va_list args;
  va_start(args, format);
  vprintf(format, args);
  va_end(args);

  printf("%s", new_line);
  fflush(stdout);
}

static void
generate_bitmap(state_t *state)
{
  // Make the forest
  kd_forest_t kdf;
  kdf_init(&kdf);

  bool animate = state->options->animate;
  unsigned int frame = 0;
  char filename[strlen(state->options->filename) + 10];

  size_t max_size = 0;

  // Do multiple passes to get rid of artifacts in HUE_SORT mode
  unsigned int bit_depth = state->options->bit_depth;
  for (unsigned int i = 1, progress = 0; i <= bit_depth + 1; ++i) {
    unsigned int stripe = 1 << i;

    for (unsigned int j = stripe/2 - 1; j < state->size; j += stripe, ++progress) {
      if (progress%state->width == 0) {
        if (animate) {
          sprintf(filename, "%s/%04u.png", state->options->filename, frame);
          write_png(state, filename);
          ++frame;
        }

        print_progress("%.2f%%\t| boundary size: %zu\t| max boundary size: %zu",
                       100.0*progress/state->size, kdf.size, max_size);
      }

      uint32_t color = state->colors[j];

      double target[KD_DIMEN];
      switch (state->options->color_space) {
      case COLOR_SPACE_RGB:
        color_set_RGB(target, color);
        break;
      case COLOR_SPACE_LAB:
        color_set_Lab(target, color);
        break;
      case COLOR_SPACE_LUV:
        color_set_Luv(target, color);
        break;
      }

      pixel_t *pixel;
      if (j == 0) {
        // First node goes in the center
        pixel = get_pixel(state, state->width/2, state->height/2);
      } else {
        pixel = find_next_pixel(state, &kdf, target);
      }

      memcpy(pixel->value, target, sizeof(target));
      insert_new_pixel(state, &kdf, pixel);
      if (kdf.size > max_size) {
        max_size = kdf.size;
      }

      png_byte *png_pixel = state->bitmap[pixel->y] + 3*pixel->x;
      color_unpack(png_pixel, color);
    }
  }

  if (animate) {
#if __unix__
    sprintf(filename, "%s/last.png", state->options->filename);
    write_png(state, filename);

    for (int i = 0; i < 120; ++i) {
      sprintf(filename, "%s/%04u.png", state->options->filename, frame + i);
      if (symlink("last.png", filename) != 0) {
        abort();
      }
    }
#else
    for (int i = 0; i < 120; ++i) {
      sprintf(filename, "%s/%04u.png", state->options->filename, frame + i);
      write_png(state, filename);
    }
#endif
  }

  print_progress("%.2f%%\t| boundary size: %zu\t| max boundary size: %zu\n",
                 100.0, kdf.size, max_size);

  kdf_destroy(&kdf);
}

static void
write_png(const state_t *state, const char *filename)
{
  FILE *file = fopen(filename, "wb");
  if (!file) {
    abort();
  }

  png_struct *png_ptr =
    png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
  if (!png_ptr) {
    abort();
  }

  png_info *info_ptr = png_create_info_struct(png_ptr);
  if (!info_ptr) {
    abort();
  }

  // libpng will longjmp here if it encounters an error from now on
  if (setjmp(png_jmpbuf(png_ptr))) {
    abort();
  }

  png_init_io(png_ptr, file);
  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, state->bitmap);
  png_write_png(png_ptr, info_ptr, PNG_TRANSFORM_IDENTITY, NULL);
  png_destroy_write_struct(&png_ptr, &info_ptr);
  fclose(file);
}