robinkrens.nl - git repository - swan-dev/blob - tools/bmp2tiles/bmp2tiles.c

   1 /**
   2  * File              : bmp2tiles.c
   3  * Author            : Robin Krens <robin@robinkrens.nl>
   4  * Date              : 04.06.2022
   5  * Last Modified Date: 12.06.2022
   6  * Last Modified By  : Robin Krens <robin@robinkrens.nl>
   7  */
   8
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <stdint.h>
  12 #include <stdbool.h>
  13 #include <string.h>
  14 #include <unistd.h>
  15 #include <getopt.h>
  16 #include <SDL2/SDL_image.h>
  17
  18 #define TILE_SZ         32
  19 #define FOURBBP_ROW     8
  20 #define FOURBPP_COL     8
  21
  22 typedef struct {
  23         unsigned width;
  24         unsigned height;
  25         unsigned row_tiles;
  26         unsigned col_tiles;
  27         unsigned bpp;
  28         unsigned char * data;
  29         SDL_Colour * palette;
  30         unsigned short outpal[8];
  31 } swan_gfx_t;
  32
  33 int set_info(swan_gfx_t * gfx, SDL_Surface * img)
  34 {
  35         gfx->width = img->w;
  36         gfx->height = img->h;
  37         gfx->bpp = img->format->BitsPerPixel;
  38
  39         if (gfx->bpp != 8) {
  40                 fprintf(stderr, "error: %d bpp format detected\n", img->format->BitsPerPixel);
  41                 return -1;
  42         }
  43
  44         if (gfx->width % 8 | gfx->height % 8) {
  45                 fprintf(stderr, "error: image not multiple of 16x16 tiles\n \
  46                                 width: %d\theight: %d\n", gfx->width, gfx->height);
  47                 return -1;
  48         }
  49
  50         gfx->row_tiles = gfx->height / 8;
  51         gfx->col_tiles = gfx->width / 8;
  52
  53         /* set userdata to iterate over
  54          * pixels */
  55         SDL_LockSurface(img);
  56         img->userdata = img->pixels;
  57         gfx->data = (unsigned char *) img->userdata;
  58         gfx->palette = img->format->palette->colors;
  59         SDL_UnlockSurface(img);
  60
  61         return 0;
  62 }
  63
  64 void generate_4bpp_tile(unsigned char *buf, swan_gfx_t * gfx,
  65                 bool packed)
  66 {
  67         unsigned char * ptr = gfx->data;
  68         for (int i = 0; i < TILE_SZ; i+=4) {
  69                 for (int j = 0; j < 4; ++j) {
  70                         if (packed) { /* packed format */
  71                                 if (ptr[0] >= 8 || ptr[1] >= 8)
  72                                         fprintf(stdout, "warning: too many colors detected\n");
  73                                 gfx->outpal[ptr[0]] = (gfx->palette[ptr[0]].r >> 4) << 8 |
  74                                                       (gfx->palette[ptr[0]].g >> 4) << 4 |
  75                                                       gfx->palette[ptr[0]].b >> 4;
  76                                 buf[i+j] = ptr[0] << 4;
  77                                 buf[i+j] |= ptr[1];
  78                                 ptr += 2;
  79                         } else { /* planar format */
  80                                 for (int x = 0; x < 8; ++x) {
  81                                         if (ptr[x] >= 8)
  82                                                 fprintf(stdout, "warning: too many colors detected\n");
  83                                         buf[i + j] = ptr[x] << j;
  84                                 }
  85                         }
  86                 }
  87                 if (!packed)
  88                         ptr += 8;
  89         }
  90 }
  91
  92 int main(int argc, char *argv[])
  93 {
  94         SDL_Surface * rawbmp;
  95         FILE * gfxstream;
  96         FILE * palstream;
  97         int opt;
  98         char * infile;
  99         char outfile[256];
 100         bool bout = false;
 101
 102         while ((opt = getopt(argc, argv, "po:sv:")) != -1) {
 103                 switch (opt) {
 104                         case 'p':
 105                                 printf("include palette");
 106                                 break;
 107                         case 'o':
 108                                 printf("output file %s\n", optarg);
 109                                 strcpy(outfile, optarg);
 110                                 bout = true;
 111                                 break;
 112                         case 's':
 113                                 printf("generate gfx per 16x16 tile \n");
 114                                 break;
 115                         case 'v':
 116                                 break;
 117                         default: /* '?' */
 118                                 fprintf(stderr, "Usage: %s [-s] [-o output] file \n", argv[0]);
 119                                 exit(EXIT_FAILURE);
 120                }
 121         }
 122
 123         if (optind >= argc) {
 124                 fprintf(stderr, "Expected infile\n");
 125                 fprintf(stderr, "Usage: %s [-s] [-o output] [file]\n", argv[0]);
 126                 exit(EXIT_FAILURE);
 127         }
 128
 129         infile = argv[optind];
 130
 131         rawbmp = SDL_LoadBMP(infile);
 132         if (!rawbmp) {
 133                 fprintf(stderr, "can not load %s file\n", infile);
 134                 exit(EXIT_FAILURE);
 135         }
 136
 137         swan_gfx_t * gfx = malloc(sizeof(swan_gfx_t));
 138         int ret = set_info(gfx, rawbmp);
 139
 140         if (ret != 0)
 141                 goto cleanup;
 142
 143         unsigned char *tile_buf = malloc(sizeof(unsigned char) * TILE_SZ);
 144
 145         if (!bout)
 146                 gfxstream = fopen("out.gfx", "w");
 147         else {
 148                 printf("opening %s\n", outfile);
 149                 gfxstream = fopen(outfile, "w");
 150         }
 151
 152         if (!gfxstream) {
 153                 fprintf(stderr, "can not open file for writing!\n");
 154                 goto close;
 155         }
 156
 157         unsigned nr_tiles = 1;
 158
 159         for (int i = 0; i < nr_tiles; ++i) {
 160                 generate_4bpp_tile(tile_buf, gfx, true);
 161                 int ret = fwrite(tile_buf, sizeof(unsigned char), TILE_SZ, gfxstream);
 162                 if (ret != TILE_SZ) {
 163                         fprintf(stderr, "failed to convert, only write %d instead of %d\n", ret, TILE_SZ);
 164                         goto cleanup;
 165                 }
 166         }
 167
 168         palstream = fopen("out.pal", "w");
 169         if (!palstream) {
 170                 fprintf(stderr, "can not open file for writing!\n");
 171                 fclose(palstream);
 172                 goto close;
 173         }
 174
 175         fwrite(gfx->outpal, sizeof(unsigned short), 8, palstream);
 176         const short fill = 0xFFFF;
 177         for (int i = 0; i < 8; ++i)
 178                 fwrite(&fill, sizeof(unsigned short), 1, palstream);
 179
 180         fclose(palstream);
 181
 182 close:
 183         fclose(gfxstream);
 184 cleanup:
 185         free(gfx);
 186         SDL_FreeSurface(rawbmp);
 187 }