some skinning capabilities

[libpicofe.git] / gp2x / readpng.c

diff --git a/gp2x/readpng.c b/gp2x/readpng.c
new file mode 100644 (file)
index 0000000..a890e4e
--- /dev/null
+++ b/gp2x/readpng.c
@@ -0,0 +1,143 @@
+#include <stdio.h>
+#include <string.h>
+#include <png.h>
+#include "readpng.h"
+
+void readpng(void *dest, const char *fname, readpng_what what)
+{
+       FILE *fp;
+       png_structp png_ptr = NULL;
+       png_infop info_ptr = NULL;
+       png_bytepp row_ptr = NULL;
+
+       if (dest == NULL || fname == NULL)
+       {
+               return;
+       }
+
+       fp = fopen(fname, "rb");
+       if (fp == NULL)
+       {
+               printf(__FILE__ ": failed to open: %s\n", fname);
+               return;
+       }
+
+       png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+       if (!png_ptr)
+       {
+               printf(__FILE__ ": png_create_read_struct() failed\n");
+               fclose(fp);
+               return;
+       }
+
+       info_ptr = png_create_info_struct(png_ptr);
+       if (!info_ptr)
+       {
+               printf(__FILE__ ": png_create_info_struct() failed\n");
+               goto done;
+       }
+
+       // Start reading
+       png_init_io(png_ptr, fp);
+       png_read_png(png_ptr, info_ptr, PNG_TRANSFORM_STRIP_16 | PNG_TRANSFORM_STRIP_ALPHA | PNG_TRANSFORM_PACKING, NULL);
+       row_ptr = png_get_rows(png_ptr, info_ptr);
+       if (row_ptr == NULL)
+       {
+               printf(__FILE__ ": png_get_rows() failed\n");
+               goto done;
+       }
+
+       // printf("%s: %ix%i @ %ibpp\n", fname, (int)info_ptr->width, (int)info_ptr->height, info_ptr->pixel_depth);
+
+       switch (what)
+       {
+               case READPNG_BG:
+               {
+                       int height, width, h;
+                       unsigned short *dst = dest;
+                       if (info_ptr->pixel_depth != 24)
+                       {
+                               printf(__FILE__ ": bg image uses %ibpp, needed 24bpp\n", info_ptr->pixel_depth);
+                               break;
+                       }
+                       height = info_ptr->height;
+                       if (height > 240) height = 240;
+                       width = info_ptr->width;
+                       if (width > 320) width = 320;
+
+                       for (h = 0; h < height; h++)
+                       {
+                               unsigned char *src = row_ptr[h];
+                               int len = width;
+                               while (len--)
+                               {
+                                       *dst++ = ((src[0]&0xf8)<<8) | ((src[1]&0xf8)<<3) | (src[2] >> 3);
+                                       src += 3;
+                               }
+                               dst += 320 - width;
+                       }
+                       break;
+               }
+
+               case READPNG_FONT:
+               {
+                       int x, y, x1, y1;
+                       unsigned char *dst = dest;
+                       if (info_ptr->width != 128 || info_ptr->height != 160)
+                       {
+                               printf(__FILE__ ": unexpected font image size %ix%i, needed 128x160\n",
+                                       (int)info_ptr->width, (int)info_ptr->height);
+                               break;
+                       }
+                       if (info_ptr->pixel_depth != 8)
+                       {
+                               printf(__FILE__ ": font image uses %ibpp, needed 8bpp\n", info_ptr->pixel_depth);
+                               break;
+                       }
+                       for (y = 0; y < 16; y++)
+                       {
+                               for (x = 0; x < 16; x++)
+                               {
+                                       for (y1 = 0; y1 < 10; y1++)
+                                       {
+                                               unsigned char *src = row_ptr[y*10 + y1] + x*8;
+                                               for (x1 = 8/2; x1 > 0; x1--, src+=2)
+                                                       *dst++ = ((src[0]^0xff) & 0xf0) | ((src[1]^0xff) >> 4);
+                                       }
+                               }
+                       }
+                       break;
+               }
+
+               case READPNG_SELECTOR:
+               {
+                       int x1, y1;
+                       unsigned char *dst = dest;
+                       if (info_ptr->width != 8 || info_ptr->height != 10)
+                       {
+                               printf(__FILE__ ": unexpected selector image size %ix%i, needed 8x10\n",
+                                       (int)info_ptr->width, (int)info_ptr->height);
+                               break;
+                       }
+                       if (info_ptr->pixel_depth != 8)
+                       {
+                               printf(__FILE__ ": selector image uses %ibpp, needed 8bpp\n", info_ptr->pixel_depth);
+                               break;
+                       }
+                       for (y1 = 0; y1 < 10; y1++)
+                       {
+                               unsigned char *src = row_ptr[y1];
+                               for (x1 = 8/2; x1 > 0; x1--, src+=2)
+                                       *dst++ = ((src[0]^0xff) & 0xf0) | ((src[1]^0xff) >> 4);
+                       }
+                       break;
+               }
+       }
+
+
+done:
+       png_destroy_read_struct(&png_ptr, info_ptr ? &info_ptr : NULL, (png_infopp)NULL);
+       fclose(fp);
+}
+
+