[devel] Added more blank lines for readability.
diff --git a/pngwtran.c b/pngwtran.c
index 6195d8e..4236e10 100644
--- a/pngwtran.c
+++ b/pngwtran.c
@@ -1,7 +1,7 @@
 
 /* pngwtran.c - transforms the data in a row for PNG writers
  *
- * Last changed in libpng 1.5.0 [April 29, 2010]
+ * Last changed in libpng 1.5.0 [May 6, 2010]
  * Copyright (c) 1998-2010 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -41,41 +41,50 @@
                /*  png_byte pixel_depth;    bits per pixel (depth*channels) */
             png_ptr->row_buf + 1);      /* start of pixel data for row */
 #endif
+
 #ifdef PNG_WRITE_FILLER_SUPPORTED
    if (png_ptr->transformations & PNG_FILLER)
       png_do_strip_filler(&(png_ptr->row_info), png_ptr->row_buf + 1,
           png_ptr->flags);
 #endif
+
 #ifdef PNG_WRITE_PACKSWAP_SUPPORTED
    if (png_ptr->transformations & PNG_PACKSWAP)
       png_do_packswap(&(png_ptr->row_info), png_ptr->row_buf + 1);
 #endif
+
 #ifdef PNG_WRITE_PACK_SUPPORTED
    if (png_ptr->transformations & PNG_PACK)
       png_do_pack(&(png_ptr->row_info), png_ptr->row_buf + 1,
           (png_uint_32)png_ptr->bit_depth);
 #endif
+
 #ifdef PNG_WRITE_SWAP_SUPPORTED
    if (png_ptr->transformations & PNG_SWAP_BYTES)
       png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1);
 #endif
+
 #ifdef PNG_WRITE_SHIFT_SUPPORTED
    if (png_ptr->transformations & PNG_SHIFT)
       png_do_shift(&(png_ptr->row_info), png_ptr->row_buf + 1,
           &(png_ptr->shift));
 #endif
+
 #ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
    if (png_ptr->transformations & PNG_SWAP_ALPHA)
       png_do_write_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
 #endif
+
 #ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
    if (png_ptr->transformations & PNG_INVERT_ALPHA)
       png_do_write_invert_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
 #endif
+
 #ifdef PNG_WRITE_BGR_SUPPORTED
    if (png_ptr->transformations & PNG_BGR)
       png_do_bgr(&(png_ptr->row_info), png_ptr->row_buf + 1);
 #endif
+
 #ifdef PNG_WRITE_INVERT_SUPPORTED
    if (png_ptr->transformations & PNG_INVERT_MONO)
       png_do_invert(&(png_ptr->row_info), png_ptr->row_buf + 1);
@@ -113,9 +122,12 @@
             {
                if (*sp != 0)
                   v |= mask;
+
                sp++;
+
                if (mask > 1)
                   mask >>= 1;
+
                else
                {
                   mask = 0x80;
@@ -124,8 +136,10 @@
                   v = 0;
                }
             }
+
             if (mask != 0x80)
                *dp = (png_byte)v;
+
             break;
          }
          case 2:
@@ -139,12 +153,14 @@
             dp = row;
             shift = 6;
             v = 0;
+
             for (i = 0; i < row_width; i++)
             {
                png_byte value;
 
                value = (png_byte)(*sp & 0x03);
                v |= (value << shift);
+
                if (shift == 0)
                {
                   shift = 6;
@@ -152,12 +168,16 @@
                   dp++;
                   v = 0;
                }
+
                else
                   shift -= 2;
+
                sp++;
             }
+
             if (shift != 6)
                *dp = (png_byte)v;
+
             break;
          }
          case 4:
@@ -171,6 +191,7 @@
             dp = row;
             shift = 4;
             v = 0;
+
             for (i = 0; i < row_width; i++)
             {
                png_byte value;
@@ -185,13 +206,16 @@
                   dp++;
                   v = 0;
                }
+
                else
                   shift -= 4;
 
                sp++;
             }
+
             if (shift != 4)
                *dp = (png_byte)v;
+
             break;
          }
       }
@@ -216,8 +240,7 @@
 {
    png_debug(1, "in png_do_shift");
 
-   if (
-      row_info->color_type != PNG_COLOR_TYPE_PALETTE)
+   if (row_info->color_type != PNG_COLOR_TYPE_PALETTE)
    {
       int shift_start[4], shift_dec[4];
       int channels = 0;
@@ -227,19 +250,23 @@
          shift_start[channels] = row_info->bit_depth - bit_depth->red;
          shift_dec[channels] = bit_depth->red;
          channels++;
+
          shift_start[channels] = row_info->bit_depth - bit_depth->green;
          shift_dec[channels] = bit_depth->green;
          channels++;
+
          shift_start[channels] = row_info->bit_depth - bit_depth->blue;
          shift_dec[channels] = bit_depth->blue;
          channels++;
       }
+
       else
       {
          shift_start[channels] = row_info->bit_depth - bit_depth->gray;
          shift_dec[channels] = bit_depth->gray;
          channels++;
       }
+
       if (row_info->color_type & PNG_COLOR_MASK_ALPHA)
       {
          shift_start[channels] = row_info->bit_depth - bit_depth->alpha;
@@ -257,8 +284,10 @@
 
          if (bit_depth->gray == 1 && row_info->bit_depth == 2)
             mask = 0x55;
+
          else if (row_info->bit_depth == 4 && bit_depth->gray == 3)
             mask = 0x11;
+
          else
             mask = 0xff;
 
@@ -269,10 +298,12 @@
 
             v = *bp;
             *bp = 0;
+
             for (j = shift_start[0]; j > -shift_dec[0]; j -= shift_dec[0])
             {
                if (j > 0)
                   *bp |= (png_byte)((v << j) & 0xff);
+
                else
                   *bp |= (png_byte)((v >> (-j)) & mask);
             }
@@ -293,10 +324,12 @@
 
             v = *bp;
             *bp = 0;
+
             for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c])
             {
                if (j > 0)
                   *bp |= (png_byte)((v << j) & 0xff);
+
                else
                   *bp |= (png_byte)((v >> (-j)) & 0xff);
             }
@@ -316,10 +349,12 @@
 
             v = (png_uint_16)(((png_uint_16)(*bp) << 8) + *(bp + 1));
             value = 0;
+
             for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c])
             {
                if (j > 0)
                   value |= (png_uint_16)((v << j) & (png_uint_16)0xffff);
+
                else
                   value |= (png_uint_16)((v >> (-j)) & (png_uint_16)0xffff);
             }
@@ -346,6 +381,7 @@
             png_bytep sp, dp;
             png_uint_32 i;
             png_uint_32 row_width = row_info->width;
+
             for (i = 0, sp = dp = row; i < row_width; i++)
             {
                png_byte save = *(sp++);
@@ -355,6 +391,7 @@
                *(dp++) = save;
             }
          }
+
          else
          {
             /* This converts from AARRGGBB to RRGGBBAA */
@@ -378,6 +415,7 @@
             }
          }
       }
+
       else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
       {
          if (row_info->bit_depth == 8)
@@ -394,6 +432,7 @@
                *(dp++) = save;
             }
          }
+
          else
          {
             /* This converts from AAGG to GGAA */
@@ -432,6 +471,7 @@
             png_bytep sp, dp;
             png_uint_32 i;
             png_uint_32 row_width = row_info->width;
+
             for (i = 0, sp = dp = row; i < row_width; i++)
             {
                /* Does nothing
@@ -443,6 +483,7 @@
                *(dp++) = (png_byte)(255 - *(sp++));
             }
          }
+
          else
          {
             /* This inverts the alpha channel in RRGGBBAA */
@@ -466,6 +507,7 @@
             }
          }
       }
+
       else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
       {
          if (row_info->bit_depth == 8)
@@ -481,6 +523,7 @@
                *(dp++) = (png_byte)(255 - *(sp++));
             }
          }
+
          else
          {
             /* This inverts the alpha channel in GGAA */
@@ -511,8 +554,7 @@
 {
    png_debug(1, "in png_do_write_intrapixel");
 
-   if (
-       (row_info->color_type & PNG_COLOR_MASK_COLOR))
+   if ((row_info->color_type & PNG_COLOR_MASK_COLOR))
    {
       int bytes_per_pixel;
       png_uint_32 row_width = row_info->width;
@@ -523,8 +565,10 @@
 
          if (row_info->color_type == PNG_COLOR_TYPE_RGB)
             bytes_per_pixel = 3;
+
          else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
             bytes_per_pixel = 4;
+
          else
             return;
 
@@ -534,6 +578,7 @@
             *(rp + 2) = (png_byte)((*(rp + 2) - *(rp + 1)) & 0xff);
          }
       }
+
       else if (row_info->bit_depth == 16)
       {
          png_bytep rp;
@@ -541,8 +586,10 @@
 
          if (row_info->color_type == PNG_COLOR_TYPE_RGB)
             bytes_per_pixel = 6;
+
          else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
             bytes_per_pixel = 8;
+
          else
             return;