Function bm_iff_parse_body

bitmap/iff.cpp:210–291

the buffer pointed to by raw_data is stuffed with a pointer to decompressed pixel data

//  the buffer pointed to by raw_data is stuffed with a pointer to decompressed pixel data
int bm_iff_parse_body(CFILE *ifile, int len, iff_bitmap_header *bmheader) {
  uint8_t *p = bmheader->raw_data;
  int width = 0, depth = 0, done = 0;

  if (bmheader->type == TYPE_PBM) {
    width = bmheader->w;
    depth = 1;
  } else if (bmheader->type == TYPE_ILBM) {
    width = (bmheader->w + 7) / 8;
    depth = bmheader->nplanes;
  }

  if (bmheader->compression == cmpNone) // no compression
  {
    for (int y = 0; y < bmheader->h; y++) {
      int x;

      for (x = 0; x < width * depth; x++)
        *p++ = cf_ReadByte(ifile);

      if (bmheader->masking == mskHasMask) {
        for (int i = 0; i < width; i++)
          cf_ReadByte(ifile); // skip mask!
      }

      if (bmheader->w & 1)
        cf_ReadByte(ifile);
    }

  } else if (bmheader->compression == cmpByteRun1) // compression
  {
    uint8_t *data_end = p + (bmheader->h * depth * width);
    uint8_t mask = (bmheader->masking == mskHasMask);
    int cur_width = 0, skip_mask = 0;
    int command;
    int plane = 0;

    while (!done) {
      if (p >= data_end) {
        done = 1;
        continue;
      }
      if (cur_width == width) {
        plane++;
        if ((plane == depth && !mask) || (plane == depth + 1 && mask)) {
          skip_mask = 0;
          plane = 0;
        }

        if (mask && plane == depth)
          skip_mask = 1;

        cur_width = 0;
      }

      command = cf_ReadByte(ifile);
      if (command >= 0 && command <= 127) {
        if (!skip_mask) {