In-tree version of FLTK needs Fl_PNG_Image in order to use the new icon code in the viewer

git-svn-id: svn://svn.code.sf.net/p/tigervnc/code/trunk@4920 3789f03b-4d11-0410-bbf8-ca57d06f2519

common/fltk/src/CMakeLists.txt

@@ -44,6 +44,7 @@ set(CPPFILES
   Fl_Pack.cxx
   Fl_Paged_Device.cxx
   Fl_Pixmap.cxx
+  Fl_PNG_Image.cxx
   Fl_Positioner.cxx
   Fl_Printer.cxx
   Fl_Preferences.cxx

common/fltk/src/Fl_PNG_Image.cxx

@@ -0,0 +1,233 @@
+//
+// "$Id: Fl_PNG_Image.cxx 8656 2011-05-12 08:07:27Z manolo $"
+//
+// Fl_PNG_Image routines.
+//
+// Copyright 1997-2011 by Easy Software Products.
+// Image support by Matthias Melcher, Copyright 2000-2009.
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Library General Public
+// License as published by the Free Software Foundation; either
+// version 2 of the License, or (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Library General Public License for more details.
+//
+// You should have received a copy of the GNU Library General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+// USA.
+//
+// Please report all bugs and problems on the following page:
+//
+//     http://www.fltk.org/str.php
+//
+// Contents:
+
+//
+//   Fl_PNG_Image::Fl_PNG_Image() - Load a PNG image file.
+//
+
+//
+// Include necessary header files...
+//
+
+#include <FL/Fl.H>
+#include <FL/Fl_PNG_Image.H>
+#include <FL/Fl_Shared_Image.H>
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <FL/fl_utf8.h>
+
+#if defined(HAVE_LIBPNG) && defined(HAVE_LIBZ)
+extern "C"
+{
+#  include <zlib.h>
+#  ifdef HAVE_PNG_H
+#    include <png.h>
+#  else
+#    include <libpng/png.h>
+#  endif // HAVE_PNG_H
+}
+
+typedef struct  {
+  png_structp pp;
+  const unsigned char *current;
+  const unsigned char *last;
+} fl_png_memory;
+
+static void png_read_data_from_mem( png_structp png_ptr, //pointer to our data
+				   png_bytep data,  // where to copy the image data for libpng computing
+				   png_size_t length) // length of data to copy
+{
+  fl_png_memory *png_mem_data = (fl_png_memory*)png_get_io_ptr(png_ptr); // get the pointer to our struct
+  if (png_mem_data->current + length > png_mem_data->last) {
+    png_error(png_mem_data->pp, "Invalid attempt to read row data");
+    return;
+  }
+  /* copy data from image buffer */
+  memcpy (data, png_mem_data->current, length);
+  /* advance in the memory data */
+  png_mem_data->current += length;
+}
+#endif // HAVE_LIBPNG && HAVE_LIBZ
+
+
+/**
+  The constructor loads the named PNG image from the given png filename.
+
+  The destructor frees all memory and server resources that are used by
+  the image.
+
+  \param[in] filename	Name of PNG file to read
+*/
+Fl_PNG_Image::Fl_PNG_Image (const char *filename): Fl_RGB_Image(0,0,0)
+{
+  load_png_(filename, NULL, 0);
+}
+
+/** 
+ \brief Constructor that reads a PNG image from memory.
+
+ Construct an image from a block of memory inside the application. Fluid offers
+ "binary Data" chunks as a great way to add image data into the C++ source code.
+ name_png can be NULL. If a name is given, the image is added to the list of 
+ shared images (see: Fl_Shared_Image) and will be available by that name.
+ 
+ \param name_png  A name given to this image or NULL
+ \param buffer	  Pointer to the start of the PNG image in memory
+ \param maxsize   Size in bytes of the memory buffer containing the PNG image
+ */
+Fl_PNG_Image::Fl_PNG_Image (
+      const char *name_png, const unsigned char *buffer, int maxsize): Fl_RGB_Image(0,0,0)
+{
+  load_png_(name_png, buffer, maxsize);
+}
+
+void Fl_PNG_Image::load_png_(const char *name_png, const unsigned char *buffer_png, int maxsize)
+{
+#if defined(HAVE_LIBPNG) && defined(HAVE_LIBZ)
+  int i;	  // Looping var
+  FILE *fp = NULL;	  // File pointer
+  int channels;	  // Number of color channels
+  png_structp pp; // PNG read pointer
+  png_infop info; // PNG info pointers
+  png_bytep *rows;// PNG row pointers
+  fl_png_memory png_mem_data;
+  int from_memory = (buffer_png != NULL); // true if reading image from memory
+
+  if (!from_memory) {
+    if ((fp = fl_fopen(name_png, "rb")) == NULL) return;
+  }
+  else name_png = "In-memory PNG data";
+
+  // Setup the PNG data structures...
+  pp = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+  if (pp) info = png_create_info_struct(pp);
+  if (!pp || !info) {
+    if (pp) png_destroy_read_struct(&pp, NULL, NULL);
+    if (!from_memory) fclose(fp);
+    Fl::warning("Cannot allocate memory to read PNG file or data \"%s\".\n", name_png);
+    return;
+  }
+  
+  if (setjmp(png_jmpbuf(pp)))
+  {
+    png_destroy_read_struct(&pp, &info, NULL);
+    if (!from_memory) fclose(fp);
+    Fl::warning("PNG file or data \"%s\" contains errors!\n", name_png);
+    return;
+  }
+
+  if (from_memory) {
+    png_mem_data.current = buffer_png;
+    png_mem_data.last = buffer_png + maxsize;
+    png_mem_data.pp = pp;
+    // Initialize the function pointer to the PNG read "engine"...
+    png_set_read_fn (pp, (png_voidp) &png_mem_data, png_read_data_from_mem);
+  } else {
+    png_init_io(pp, fp); // Initialize the PNG file read "engine"...
+  }  
+
+  // Get the image dimensions and convert to grayscale or RGB...
+  png_read_info(pp, info);
+
+  if (png_get_color_type(pp, info) == PNG_COLOR_TYPE_PALETTE)
+    png_set_expand(pp);
+
+  if (png_get_color_type(pp, info) & PNG_COLOR_MASK_COLOR)
+    channels = 3;
+  else
+    channels = 1;
+
+  int num_trans = 0;
+  png_get_tRNS(pp, info, 0, &num_trans, 0);
+  if ((png_get_color_type(pp, info) & PNG_COLOR_MASK_ALPHA) || (num_trans != 0))
+    channels ++;
+
+  w((int)(png_get_image_width(pp, info)));
+  h((int)(png_get_image_height(pp, info)));
+  d(channels);
+
+  if (png_get_bit_depth(pp, info) < 8)
+  {
+    png_set_packing(pp);
+    png_set_expand(pp);
+  }
+  else if (png_get_bit_depth(pp, info) == 16)
+    png_set_strip_16(pp);
+
+#  if defined(HAVE_PNG_GET_VALID) && defined(HAVE_PNG_SET_TRNS_TO_ALPHA)
+  // Handle transparency...
+  if (png_get_valid(pp, info, PNG_INFO_tRNS))
+    png_set_tRNS_to_alpha(pp);
+#  endif // HAVE_PNG_GET_VALID && HAVE_PNG_SET_TRNS_TO_ALPHA
+
+  array = new uchar[w() * h() * d()];
+  alloc_array = 1;
+
+  // Allocate pointers...
+  rows = new png_bytep[h()];
+
+  for (i = 0; i < h(); i ++)
+    rows[i] = (png_bytep)(array + i * w() * d());
+
+  // Read the image, handling interlacing as needed...
+  for (i = png_set_interlace_handling(pp); i > 0; i --)
+    png_read_rows(pp, rows, NULL, h());
+
+#ifdef WIN32
+  // Some Windows graphics drivers don't honor transparency when RGB == white
+  if (channels == 4) {
+    // Convert RGB to 0 when alpha == 0...
+    uchar *ptr = (uchar *)array;
+    for (i = w() * h(); i > 0; i --, ptr += 4)
+      if (!ptr[3]) ptr[0] = ptr[1] = ptr[2] = 0;
+  }
+#endif // WIN32
+
+  // Free memory and return...
+  delete[] rows;
+
+  png_read_end(pp, info);
+  png_destroy_read_struct(&pp, &info, NULL);
+
+  if (from_memory) {
+    if (w() && h() && name_png) {
+      Fl_Shared_Image *si = new Fl_Shared_Image(name_png, this);
+      si->add();
+    }
+  } else {
+    fclose(fp);
+  }
+#endif // HAVE_LIBPNG && HAVE_LIBZ
+}
+
+
+//
+// End of "$Id: Fl_PNG_Image.cxx 8656 2011-05-12 08:07:27Z manolo $".
+//