git.y1.nz

gbdk-2020

GameBoy Development Kit
download: https://git.y1.nz/archives/gbdk.tar.gz
README | Files | Log | Refs | LICENSE

gbdk-support/png2hicolorgb/src/tile_dedupe.c

      1 #include <stdio.h>
      2 #include <string.h>
      3 #include <stdint.h>
      4 #include <stdbool.h>
      5 
      6 #include <common.h>
      7 #include <defines.h>
      8 #include <logging.h>
      9 #include <options.h>
     10 
     11 
     12 static void tile_calc_flip_gb2bpp(uint8_t * flipped_tile, const uint8_t* src_tile, bool flip_x, bool flip_y);
     13 static void tile_generate_flips(const uint8_t * p_src_tile);
     14 
     15 uint8_t tile_permutations[4 * TILE_SZ];
     16 #define FLIP_X_YES true
     17 #define FLIP_X_NO  false
     18 #define FLIP_Y_YES true
     19 #define FLIP_Y_NO  false
     20 
     21 // These should match the order of tile flip permutations in tile_generate_flips()
     22 const uint8_t tile_flip_flags[] = {
     23     CGB_ATTR_NO_FLIP,
     24     CGB_ATTR_HFLIP,
     25     CGB_ATTR_VFLIP,
     26     CGB_ATTR_HFLIP | CGB_ATTR_VFLIP};
     27 
     28 
     29 const uint8_t bits_reverse_LUT[256] = {
     30     0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0,
     31     0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0,
     32     0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8,
     33     0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8,
     34     0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4,
     35     0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4,
     36     0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec,
     37     0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc,
     38     0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2,
     39     0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2,
     40     0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea,
     41     0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa,
     42     0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6,
     43     0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6,
     44     0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee,
     45     0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe,
     46     0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1,
     47     0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1,
     48     0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9,
     49     0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9,
     50     0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5,
     51     0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5,
     52     0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed,
     53     0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd,
     54     0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3,
     55     0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3,
     56     0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb,
     57     0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb,
     58     0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7,
     59     0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7,
     60     0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef,
     61     0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff,
     62 };
     63 
     64 
     65 static void tile_calc_flip_gb2bpp(uint8_t * flipped_tile, const uint8_t * src_tile, bool flip_x, bool flip_y)
     66 {
     67     for (int ty = 0; ty < TILE_HEIGHT_PX; ty++) {
     68         int y = flip_y ? (TILE_HEIGHT_PX - 1 - ty) : ty;
     69         flipped_tile[2 * ty]     = flip_x ? bits_reverse_LUT[src_tile[2 * y]]     : src_tile[2 * y];
     70         flipped_tile[2 * ty + 1] = flip_x ? bits_reverse_LUT[src_tile[2 * y + 1]] : src_tile[2 * y + 1];
     71     }
     72 }
     73 
     74 
     75 // Generate all the X/Y flipped combinations of a 2bpp Game Boy tile
     76 // Output is used for testing if CGB flipping map attributes allow for tile pattern deduplciation
     77 //
     78 // tile_permutations[] should be 4 x 16 bytes
     79 static void tile_generate_flips(const uint8_t * p_src_tile)
     80 {
     81     tile_calc_flip_gb2bpp(&tile_permutations[0 * TILE_SZ], p_src_tile, FLIP_X_NO,  FLIP_Y_NO);
     82     tile_calc_flip_gb2bpp(&tile_permutations[1 * TILE_SZ], p_src_tile, FLIP_X_YES, FLIP_Y_NO);
     83     tile_calc_flip_gb2bpp(&tile_permutations[2 * TILE_SZ], p_src_tile, FLIP_X_NO,  FLIP_Y_YES);
     84     tile_calc_flip_gb2bpp(&tile_permutations[3 * TILE_SZ], p_src_tile, FLIP_X_YES, FLIP_Y_YES);
     85 }
     86 
     87 
     88 // bool tileset_find_matching_tile(unsigned int source_tile_id, unsigned int * TileCountDeduped, uint8_t * new_tile_id, uint8_t * new_attribs)
     89 bool tileset_find_matching_tile(const uint8_t * src_tile, const uint8_t * tile_set_deduped, const unsigned int tile_count_deduped, uint8_t * new_tile_id, uint8_t * new_attribs)
     90 {
     91     tile_generate_flips(src_tile);
     92 
     93     for (unsigned int index_dedupe = 0; index_dedupe < tile_count_deduped; index_dedupe++) {
     94 
     95         for (size_t f = 0; f < ARRAY_LEN(tile_flip_flags); f++) {
     96             if (memcmp(&tile_set_deduped[index_dedupe * TILE_SZ], &tile_permutations[f * TILE_SZ], TILE_SZ) == 0) {
     97 
     98                 // Match Found
     99                 *new_tile_id = (uint8_t)(index_dedupe & 0xFFu);
    100                 *new_attribs = (index_dedupe < CGB_TILES_START_BANK_1) ? CGB_ATTR_TILES_BANK_0 : CGB_ATTR_TILES_BANK_1;
    101                 *new_attribs |= tile_flip_flags[f];
    102                 // log_debug(" * Tile Dedupe MATCH. new ID -> %d (dedupe count=%d), new_tile_id=%d, new_attribs=0x%02x, flip_index=%d\n", *new_tile_id, tile_count_deduped, *new_tile_id, *new_attribs, f);
    103                 return true;
    104             }
    105         }
    106     }
    107     return false;  // No match found
    108 }
    109 

This webpage is intended to be an accessible preview of this repository. To get a fuller picture, clone it and use the git CLI.