platform/common/readpng.c

   1 #include <stdio.h>
   2 #include <string.h>
   3 #include <png.h>
   4 #include "readpng.h"
   5 #include "lprintf.h"
   6
   7 void readpng(void *dest, const char *fname, readpng_what what)
   8 {
   9         FILE *fp;
  10         png_structp png_ptr = NULL;
  11         png_infop info_ptr = NULL;
  12         png_bytepp row_ptr = NULL;
  13
  14         if (dest == NULL || fname == NULL)
  15         {
  16                 return;
  17         }
  18
  19         fp = fopen(fname, "rb");
  20         if (fp == NULL)
  21         {
  22                 lprintf(__FILE__ ": failed to open: %s\n", fname);
  23                 return;
  24         }
  25
  26         png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
  27         if (!png_ptr)
  28         {
  29                 lprintf(__FILE__ ": png_create_read_struct() failed\n");
  30                 fclose(fp);
  31                 return;
  32         }
  33
  34         info_ptr = png_create_info_struct(png_ptr);
  35         if (!info_ptr)
  36         {
  37                 lprintf(__FILE__ ": png_create_info_struct() failed\n");
  38                 goto done;
  39         }
  40
  41         // Start reading
  42         png_init_io(png_ptr, fp);
  43         png_read_png(png_ptr, info_ptr, PNG_TRANSFORM_STRIP_16 | PNG_TRANSFORM_STRIP_ALPHA | PNG_TRANSFORM_PACKING, NULL);
  44         row_ptr = png_get_rows(png_ptr, info_ptr);
  45         if (row_ptr == NULL)
  46         {
  47                 lprintf(__FILE__ ": png_get_rows() failed\n");
  48                 goto done;
  49         }
  50
  51         // lprintf("%s: %ix%i @ %ibpp\n", fname, (int)info_ptr->width, (int)info_ptr->height, info_ptr->pixel_depth);
  52
  53         switch (what)
  54         {
  55                 case READPNG_BG:
  56                 {
  57                         int height, width, h;
  58                         unsigned short *dst = dest;
  59                         if (info_ptr->pixel_depth != 24)
  60                         {
  61                                 lprintf(__FILE__ ": bg image uses %ibpp, needed 24bpp\n", info_ptr->pixel_depth);
  62                                 break;
  63                         }
  64                         height = info_ptr->height;
  65                         if (height > 240) height = 240;
  66                         width = info_ptr->width;
  67                         if (width > 320) width = 320;
  68
  69                         for (h = 0; h < height; h++)
  70                         {
  71                                 unsigned char *src = row_ptr[h];
  72                                 int len = width;
  73                                 while (len--)
  74                                 {
  75                                         *dst++ = ((src[0]&0xf8)<<8) | ((src[1]&0xf8)<<3) | (src[2] >> 3);
  76                                         src += 3;
  77                                 }
  78                                 dst += 320 - width;
  79                         }
  80                         break;
  81                 }
  82
  83                 case READPNG_FONT:
  84                 {
  85                         int x, y, x1, y1;
  86                         unsigned char *dst = dest;
  87                         if (info_ptr->width != 128 || info_ptr->height != 160)
  88                         {
  89                                 lprintf(__FILE__ ": unexpected font image size %ix%i, needed 128x160\n",
  90                                         (int)info_ptr->width, (int)info_ptr->height);
  91                                 break;
  92                         }
  93                         if (info_ptr->pixel_depth != 8)
  94                         {
  95                                 lprintf(__FILE__ ": font image uses %ibpp, needed 8bpp\n", info_ptr->pixel_depth);
  96                                 break;
  97                         }
  98                         for (y = 0; y < 16; y++)
  99                         {
 100                                 for (x = 0; x < 16; x++)
 101                                 {
 102                                         for (y1 = 0; y1 < 10; y1++)
 103                                         {
 104                                                 unsigned char *src = row_ptr[y*10 + y1] + x*8;
 105                                                 for (x1 = 8/2; x1 > 0; x1--, src+=2)
 106                                                         *dst++ = ((src[0]^0xff) & 0xf0) | ((src[1]^0xff) >> 4);
 107                                         }
 108                                 }
 109                         }
 110                         break;
 111                 }
 112
 113                 case READPNG_SELECTOR:
 114                 {
 115                         int x1, y1;
 116                         unsigned char *dst = dest;
 117                         if (info_ptr->width != 8 || info_ptr->height != 10)
 118                         {
 119                                 lprintf(__FILE__ ": unexpected selector image size %ix%i, needed 8x10\n",
 120                                         (int)info_ptr->width, (int)info_ptr->height);
 121                                 break;
 122                         }
 123                         if (info_ptr->pixel_depth != 8)
 124                         {
 125                                 lprintf(__FILE__ ": selector image uses %ibpp, needed 8bpp\n", info_ptr->pixel_depth);
 126                                 break;
 127                         }
 128                         for (y1 = 0; y1 < 10; y1++)
 129                         {
 130                                 unsigned char *src = row_ptr[y1];
 131                                 for (x1 = 8/2; x1 > 0; x1--, src+=2)
 132                                         *dst++ = ((src[0]^0xff) & 0xf0) | ((src[1]^0xff) >> 4);
 133                         }
 134                         break;
 135                 }
 136         }
 137
 138
 139 done:
 140         png_destroy_read_struct(&png_ptr, info_ptr ? &info_ptr : NULL, (png_infopp)NULL);
 141         fclose(fp);
 142 }
 143
 144