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dougallj/draw-patterns.c

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  1. dougallj revised this gist Sep 16, 2016. No changes.
  2. dougallj created this gist Sep 16, 2016.
    116 changes: 116 additions & 0 deletions draw-patterns.c
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    Original file line number Diff line number Diff line change
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    #define STB_IMAGE_WRITE_IMPLEMENTATION
    #include "stb_image_write.h"

    #define WIDTH_IN_BLOCKS 29
    #define HEIGHT_IN_BLOCKS 28

    #define PADDING 4

    #define BLOCK_WIDTH (4 * 4)
    #define BLOCK_HEIGHT (4 * 4)

    #define PADDED_BLOCK_WIDTH (BLOCK_WIDTH + PADDING)
    #define PADDED_BLOCK_HEIGHT (BLOCK_HEIGHT + PADDING)

    #define IMAGE_WIDTH (PADDED_BLOCK_WIDTH * WIDTH_IN_BLOCKS + PADDING)
    #define IMAGE_HEIGHT (PADDED_BLOCK_HEIGHT * HEIGHT_IN_BLOCKS + PADDING)

    unsigned char output[IMAGE_WIDTH * IMAGE_HEIGHT];

    #define SET(x, y) (output[(y)*IMAGE_WIDTH + (x)] = 0xFF)

    void draw_pattern(int x, int y, int w, int h, int p) {
    int x1, y1;
    for (y1 = 0; y1 < h; y1++)
    for (x1 = 0; x1 < w; x1++)
    if ((p >> ((y1 % 4) * 4 + (x1 % 4))) & 1)
    SET(x + x1, y + y1);
    }

    unsigned short patterns[] = {
    0, 1, 3, 5, 7, 15, 18, 19, 20, 21, 22,
    23, 26, 27, 30, 31, 51, 53, 54, 55, 60, 61,
    63, 85, 87, 90, 91, 95, 119, 123, 125, 127, 255,
    260, 261, 262, 263, 266, 267, 270, 271, 278, 279, 282,
    283, 286, 287, 292, 293, 294, 295, 296, 297, 298, 299,
    300, 301, 302, 303, 310, 311, 312, 313, 314, 315, 316,
    317, 318, 319, 325, 326, 327, 330, 331, 334, 335, 340,
    341, 342, 343, 346, 347, 350, 351, 357, 358, 359, 360,
    361, 362, 363, 364, 365, 366, 367, 372, 373, 374, 375,
    376, 377, 378, 379, 380, 381, 382, 383, 417, 419, 420,
    421, 422, 423, 426, 427, 430, 431, 433, 435, 436, 437,
    438, 439, 442, 443, 446, 447, 481, 483, 485, 486, 487,
    490, 491, 494, 495, 497, 498, 499, 500, 501, 502, 503,
    506, 507, 510, 511, 780, 781, 783, 796, 797, 798, 799,
    828, 829, 831, 837, 839, 841, 842, 843, 845, 846, 847,
    854, 855, 857, 858, 859, 860, 861, 862, 863, 869, 871,
    873, 874, 875, 876, 877, 878, 879, 886, 887, 889, 890,
    891, 892, 893, 894, 895, 963, 965, 967, 973, 975, 979,
    981, 982, 983, 986, 987, 989, 990, 991, 1011, 1013, 1014,
    1015, 1020, 1021, 1023, 1285, 1287, 1290, 1291, 1295, 1303, 1306,
    1307, 1310, 1311, 1317, 1319, 1323, 1325, 1327, 1335, 1338, 1339,
    1341, 1342, 1343, 1365, 1367, 1370, 1371, 1375, 1397, 1399, 1402,
    1403, 1405, 1407, 1445, 1447, 1451, 1455, 1461, 1463, 1467, 1470,
    1471, 1525, 1527, 1530, 1531, 1535, 1803, 1805, 1807, 1819, 1821,
    1822, 1823, 1837, 1839, 1851, 1853, 1854, 1855, 1879, 1883, 1885,
    1887, 1911, 1915, 1917, 1919, 1927, 1935, 1943, 1950, 1951, 1959,
    1965, 1967, 1975, 1981, 1982, 1983, 2007, 2015, 2039, 2043, 2045,
    2047, 3855, 3871, 3903, 3935, 3967, 4095, 4382, 4383, 4396, 4397,
    4398, 4399, 4414, 4415, 4426, 4427, 4430, 4431, 4442, 4443, 4446,
    4447, 4458, 4459, 4460, 4461, 4462, 4463, 4474, 4475, 4477, 4478,
    4479, 4526, 4527, 4542, 4543, 4590, 4591, 4607, 4680, 4681, 4682,
    4683, 4685, 4687, 4698, 4699, 4700, 4701, 4702, 4703, 4713, 4715,
    4716, 4717, 4718, 4719, 4731, 4732, 4733, 4734, 4735, 4740, 4741,
    4743, 4748, 4749, 4750, 4751, 4758, 4759, 4764, 4765, 4766, 4767,
    4780, 4781, 4782, 4783, 4791, 4796, 4797, 4798, 4799, 4812, 4813,
    4814, 4815, 4829, 4830, 4831, 4845, 4847, 4863, 4940, 4941, 4942,
    4943, 4958, 4959, 4972, 4973, 4974, 4975, 4990, 4991, 5004, 5005,
    5006, 5007, 5020, 5021, 5022, 5023, 5036, 5037, 5038, 5039, 5052,
    5053, 5054, 5055, 5066, 5067, 5068, 5069, 5070, 5071, 5082, 5083,
    5084, 5085, 5086, 5087, 5097, 5099, 5100, 5101, 5102, 5103, 5113,
    5115, 5116, 5117, 5118, 5119, 5146, 5147, 5150, 5151, 5178, 5179,
    5180, 5181, 5182, 5183, 5210, 5211, 5214, 5215, 5242, 5243, 5245,
    5246, 5247, 5290, 5291, 5294, 5295, 5307, 5310, 5311, 5355, 5359,
    5375, 5406, 5407, 5420, 5421, 5422, 5423, 5438, 5439, 5450, 5451,
    5455, 5466, 5467, 5470, 5471, 5482, 5483, 5484, 5485, 5486, 5487,
    5498, 5499, 5500, 5501, 5502, 5503, 5541, 5542, 5543, 5546, 5547,
    5550, 5551, 5557, 5558, 5559, 5562, 5563, 5566, 5567, 5605, 5606,
    5607, 5610, 5611, 5614, 5615, 5621, 5622, 5623, 5626, 5627, 5630,
    5631, 5722, 5723, 5724, 5725, 5726, 5727, 5754, 5755, 5756, 5757,
    5758, 5759, 5767, 5775, 5783, 5790, 5791, 5799, 5803, 5804, 5805,
    5806, 5807, 5815, 5819, 5820, 5821, 5822, 5823, 5834, 5835, 5837,
    5838, 5839, 5847, 5850, 5851, 5853, 5854, 5855, 5867, 5868, 5869,
    5870, 5871, 5879, 5882, 5883, 5884, 5885, 5886, 5887, 5965, 5967,
    5982, 5983, 5997, 5999, 6014, 6015, 6023, 6030, 6031, 6039, 6046,
    6047, 6055, 6061, 6062, 6063, 6071, 6077, 6078, 6079, 6087, 6090,
    6091, 6094, 6095, 6103, 6106, 6107, 6110, 6111, 6119, 6122, 6123,
    6125, 6126, 6127, 6135, 6138, 6139, 6141, 6142, 6143, 6730, 6731,
    6735, 6746, 6747, 6750, 6751, 6763, 6766, 6767, 6779, 6782, 6783,
    6890, 6891, 6894, 6895, 6906, 6907, 6910, 6911, 6990, 6991, 7006,
    7007, 7022, 7023, 7038, 7039, 7147, 7150, 7151, 7163, 7166, 7167,
    7710, 7711, 7742, 7743, 7774, 7775, 7791, 7806, 7807, 7854, 7855,
    7870, 7871, 7918, 7919, 7934, 7935, 7967, 7983, 7999, 8015, 8031,
    8047, 8063, 8111, 8127, 8175, 8191, 13260, 13261, 13263, 13278, 13279,
    13311, 13726, 13727, 13740, 13741, 13742, 13743, 13758, 13759, 13770, 13771,
    13775, 13786, 13787, 13790, 13791, 13801, 13803, 13804, 13805, 13806, 13807,
    13817, 13818, 13819, 13820, 13821, 13822, 13823, 14025, 14027, 14031, 14043,
    14045, 14047, 14063, 14079, 14285, 14286, 14287, 14302, 14303, 14316, 14317,
    14318, 14319, 14334, 14335, 15420, 15421, 15423, 15485, 15486, 15487, 15615,
    15677, 15678, 15679, 15710, 15711, 15725, 15727, 15741, 15742, 15743, 15789,
    15791, 15805, 15807, 15838, 15839, 15853, 15855, 15869, 15870, 15871, 16191,
    16223, 16239, 16255, 16335, 16351, 16383, 23130, 23131, 23135, 23163, 23167,
    23295, 23390, 23391, 23422, 23423, 23531, 23535, 23547, 23550, 23551, 24415,
    24447, 24495, 24511, 24575, 31710, 31711, 31725, 31727, 31743, 32255, 32735,
    32767, 65535,
    };

    int main() {
    for (unsigned i = 0; i < (sizeof patterns / sizeof patterns[0]); i++) {
    int x1 = PADDING + (i % WIDTH_IN_BLOCKS) * PADDED_BLOCK_WIDTH;
    int y1 = PADDING + (i / WIDTH_IN_BLOCKS) * PADDED_BLOCK_HEIGHT;
    draw_pattern(x1, y1, BLOCK_WIDTH, BLOCK_HEIGHT, patterns[i]);
    }
    stbi_write_png("patterns.png", IMAGE_WIDTH, IMAGE_HEIGHT, 1, output,
    IMAGE_WIDTH);
    return 0;
    }
    87 changes: 87 additions & 0 deletions find-distinct-patterns.c
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    @@ -0,0 +1,87 @@
    #include <stdio.h>

    static unsigned int rotate(unsigned int p, int d) {
    // clockwise rotation
    // before: after:
    // 0 1 2 3 c 8 4 0
    // 4 5 6 7 d 9 5 1
    // 8 9 a b e a 6 2
    // c d e f f b 7 3
    int i;
    for (i = 0; i < d * 2; i++) {
    p = (p | (p << 8)) & 0x00ff00ff;
    p = (p | (p << 4)) & 0x0f0f0f0f;
    p = (p | (p << 2)) & 0x33333333;
    p = (p | (p << 1)) & 0x55555555;
    p = ((p << 1) | (p >> 16)) & 0xFFFF;
    }
    return p;
    }

    static unsigned int flip(unsigned int p) {
    p = ((p >> 4) & 0x0F0F0F0F) | ((p & 0x0F0F0F0F) << 4);
    p = ((p >> 8) & 0x00FF00FF) | ((p & 0x00FF00FF) << 8);
    return p;
    }

    static unsigned int transpose_x(unsigned int p, int d) {
    int i;
    for (i = 0; i < d; i++)
    p = ((p & 0x7777) << 1) | ((p & 0x8888) >> 3);
    return p;
    }

    static unsigned int transpose_y(unsigned int p, int d) {
    int i;
    for (int i = 0; i < d; i++)
    p = ((p & 0x0FFF) << 4) | ((p & 0xF000) >> 12);
    return p;
    }

    static unsigned int transpose(unsigned int p, int x, int y) {
    return transpose_x(transpose_y(p, y), x);
    }

    #if 0
    static unsigned int invert(unsigned int p) { return p ^ 0xFFFF; }

    static void print_pattern(unsigned int p) {
    for (int y = 0; y < 4; y++) {
    for (int x = 0; x < 4; x++) {
    printf("%s", ((p >> ((y % 4) * 4 + (x % 4))) & 1) ? "[]" : "..");
    }
    putchar('\n');
    }
    printf("-\n");
    }
    #endif

    #define NUM_PATTERNS 0x10000

    unsigned char seen[NUM_PATTERNS];

    int main() {
    int count = 0, x, y, r;
    unsigned i, p;
    for (i = 0; i < NUM_PATTERNS; i++) {
    if (seen[i])
    continue;
    count++;
    printf("%d, ", i);
    for (x = 0; x < 4; x++) {
    for (y = 0; y < 4; y++) {
    for (r = 0; r < 4; r++) {
    p = rotate(transpose_y(transpose_x(i, x), y), r);
    seen[p] = 1;
    seen[flip(p)] = 1;
    #if 0
    seen[invert(p)] = 1;
    seen[invert(flip(p))] = 1;
    #endif
    }
    }
    }
    }
    printf("\n");
    return 0;
    }