Write C++ libdimension-png wrapper.

9 files changed, 428 insertions, 6 deletions

diff --git a/libdimensionxx/Makefile.am b/libdimensionxx/Makefile.am
index 39687fe..da8f544 100644
--- a/libdimensionxx/Makefile.am
+++ b/libdimensionxx/Makefile.am
@@ -17,12 +17,12 @@
 ## along with this program.  If not, see <http://www.gnu.org/licenses/>. ##
 ###########################################################################
 
-nobase_include_HEADERS = dimensionxx.hpp dimensionxx/geometry.hpp dimensionxx/color.hpp dimensionxx/canvas.hpp
+nobase_include_HEADERS = dimensionxx.hpp dimensionxx/canvas.hpp dimensionxx/color.hpp dimensionxx/cookie.hpp dimensionxx/geometry.hpp dimensionxx/png.hpp
 
 INCLUDES = -I../libdimension -I../libdimension-png
 
 lib_LTLIBRARIES = libdimensionxx.la
 
-libdimensionxx_la_SOURCES = dimensionxx.hpp dimensionxx/geometry.hpp dimensionxx/color.hpp dimensionxx/canvas.hpp canvas.cpp color.cpp geometry.cpp
+libdimensionxx_la_SOURCES = $(nobase_include_HEADERS) canvas.cpp color.cpp cookie.cpp geometry.cpp png.cpp
 libdimensionxx_la_LDFLAGS = -version-info 0:0:0
 libdimensionxx_la_LIBADD  = ../libdimension/libdimension.la ../libdimension-png/libdimension-png.la
diff --git a/libdimensionxx/cookie.cpp b/libdimensionxx/cookie.cpp
new file mode 100644
index 0000000..dd8a06d
--- /dev/null
+++ b/libdimensionxx/cookie.cpp
@@ -0,0 +1,163 @@
+/*************************************************************************
+ * Copyright (C) 2008 Tavian Barnes <tavianator@gmail.com>               *
+ *                                                                       *
+ * This file is part of The Dimension Library.                           *
+ *                                                                       *
+ * The Dimension Library is free software; you can redistribute it and/  *
+ * or modify it under the terms of the GNU Lesser General Public License *
+ * as published by the Free Software Foundation; either version 3 of the *
+ * License, or (at your option) any later version.                       *
+ *                                                                       *
+ * The Dimension 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  *
+ * Lesser General Public License for more details.                       *
+ *                                                                       *
+ * You should have received a copy of the GNU Lesser General Public      *
+ * License along with this program.  If not, see                         *
+ * <http://www.gnu.org/licenses/>.                                       *
+ *************************************************************************/
+
+#include "dimensionxx.hpp"
+#include <stdio.h>
+
+namespace Dimension
+{
+  namespace
+  {
+    struct Cookie
+    {
+    public:
+      std::istream* istr;
+      std::ostream* ostr;
+    };
+
+    ssize_t
+    cookie_read(void* cookie, char* buf, size_t size)
+    {
+      Cookie* streams = reinterpret_cast<Cookie*>(cookie);
+
+      streams->istr->read(buf, size);
+
+      if (streams->istr->eof()) {
+        return streams->istr->gcount();
+      } else if (!streams->istr->good()) {
+        return -1;
+      } else {
+        return streams->istr->gcount();
+      }
+    }
+
+    ssize_t
+    cookie_write(void* cookie, const char* buf, size_t size)
+    {
+      Cookie* streams = reinterpret_cast<Cookie*>(cookie);
+
+      streams->ostr->write(buf, size);
+
+      if (!streams->ostr->good()) {
+        return -1;
+      } else {
+        return size;
+      }
+    }
+
+    int
+    cookie_seek(void* cookie, off64_t* offset, int whence)
+    {
+      Cookie* streams = reinterpret_cast<Cookie*>(cookie);
+      bool success = true;
+
+      if (streams->istr) {
+        switch (whence) {
+        case SEEK_SET:
+          streams->istr->seekg(*offset, std::ios::beg);
+          break;
+        case SEEK_CUR:
+          streams->istr->seekg(*offset, std::ios::cur);
+          break;
+        case SEEK_END:
+          streams->istr->seekg(*offset, std::ios::end);
+          break;
+        }
+
+        if (!streams->istr->good()) {
+          success = false;
+        }
+      }
+
+      if (streams->ostr) {
+        switch (whence) {
+        case SEEK_SET:
+          streams->ostr->seekp(*offset, std::ios::beg);
+          break;
+        case SEEK_CUR:
+          streams->ostr->seekp(*offset, std::ios::cur);
+          break;
+        case SEEK_END:
+          streams->ostr->seekp(*offset, std::ios::end);
+        }
+
+        if (!streams->ostr->good()) {
+          success = false;
+        }
+      }
+
+      return !success;
+    }
+
+    int
+    cookie_close(void* cookie)
+    {
+      delete reinterpret_cast<Cookie*>(cookie);
+    }
+  }
+
+  std::FILE*
+  fcookie(std::istream& istr)
+  {
+    Cookie* cookie = new Cookie;
+    cookie->istr = &istr;
+    cookie->ostr = 0;
+
+    cookie_io_functions_t io_funcs;
+    io_funcs.read  = &cookie_read;
+    io_funcs.write = 0;
+    io_funcs.seek  = &cookie_seek;
+    io_funcs.close = &cookie_close;
+
+    return fopencookie(reinterpret_cast<void*>(cookie), "r", io_funcs);
+  }
+
+  std::FILE*
+  fcookie(std::ostream& ostr)
+  {
+    Cookie* cookie = new Cookie;
+    cookie->istr = 0;
+    cookie->ostr = &ostr;
+
+    cookie_io_functions_t io_funcs;
+    io_funcs.read  = 0;
+    io_funcs.write = &cookie_write;
+    io_funcs.seek  = &cookie_seek;
+    io_funcs.close = &cookie_close;
+
+    return fopencookie(reinterpret_cast<void*>(cookie), "w", io_funcs);
+  }
+
+  std::FILE*
+  fcookie(std::iostream& iostr)
+  {
+    Cookie* cookie = new Cookie;
+    cookie->istr = &iostr;
+    cookie->ostr = &iostr;
+
+    cookie_io_functions_t io_funcs;
+    io_funcs.read  = &cookie_read;
+    io_funcs.write = &cookie_write;
+    io_funcs.seek  = &cookie_seek;
+    io_funcs.close = &cookie_close;
+
+    return fopencookie(reinterpret_cast<void*>(cookie), "r+", io_funcs);
+  }
+}
diff --git a/libdimensionxx/dimensionxx.hpp b/libdimensionxx/dimensionxx.hpp
index a9e89d8..7714f73 100644
--- a/libdimensionxx/dimensionxx.hpp
+++ b/libdimensionxx/dimensionxx.hpp
@@ -21,9 +21,16 @@
 #ifndef DIMENSIONXX_HPP
 #define DIMENSIONXX_HPP
 
-/* More includes */
+// Internal helpers
+#include <dimensionxx/cookie.hpp>
+
+// libdimension wrappers
+#include <dimensionxx/error.hpp>
 #include <dimensionxx/geometry.hpp>
 #include <dimensionxx/color.hpp>
 #include <dimensionxx/canvas.hpp>
 
+// libdimension-png wrapper
+#include <dimensionxx/png.hpp>
+
 #endif /* DIMENSIONXX_HPP */
diff --git a/libdimensionxx/dimensionxx/canvas.hpp b/libdimensionxx/dimensionxx/canvas.hpp
index f51aa75..c501413 100644
--- a/libdimensionxx/dimensionxx/canvas.hpp
+++ b/libdimensionxx/dimensionxx/canvas.hpp
@@ -26,10 +26,14 @@ namespace Dimension
   class Canvas
   {
   public:
-    Canvas(unsigned int x, unsigned int y)
-      : m_canvas(dmnsn_new_canvas(x, y)) { }
+    Canvas(unsigned int width, unsigned int height)
+      : m_canvas(dmnsn_new_canvas(width, height)) { }
+    explicit Canvas(dmnsn_canvas* canvas) : m_canvas(canvas) { }
     virtual ~Canvas();
 
+    unsigned int width()  const { return m_canvas->x; }
+    unsigned int height() const { return m_canvas->y; }
+
     Color pixel(unsigned int x, unsigned int y) const
       { return Color(dmnsn_get_pixel(m_canvas, x, y)); }
     void pixel(unsigned int x, unsigned int y, const Color& c)
@@ -38,9 +42,12 @@ namespace Dimension
     dmnsn_canvas*       dmnsn()       { return m_canvas; }
     const dmnsn_canvas* dmnsn() const { return m_canvas; }
 
-  private:
+  protected:
+    Canvas() : m_canvas(0) { }
+
     dmnsn_canvas* m_canvas;
 
+  private:
     // Copying prohibited
     Canvas(const Canvas&);
     Canvas& operator=(const Canvas&);
diff --git a/libdimensionxx/dimensionxx/color.hpp b/libdimensionxx/dimensionxx/color.hpp
index 5db041a..afd7ea5 100644
--- a/libdimensionxx/dimensionxx/color.hpp
+++ b/libdimensionxx/dimensionxx/color.hpp
@@ -51,6 +51,8 @@ namespace Dimension
     double trans(double t)  { m_color.trans = t; }
 
     // Color& operator=(const Color& c);
+    Color& operator+=(const Color& c)
+      { m_color = dmnsn_color_add(m_color, c.m_color); return *this; }
 
     dmnsn_color dmnsn() const { return m_color; }
 
@@ -61,6 +63,7 @@ namespace Dimension
   class CIE_XYZ
   {
   public:
+    CIE_XYZ() { }
     CIE_XYZ(double X, double Y, double Z)
       { m_XYZ.X = X; m_XYZ.Y = Y; m_XYZ.Z = Z; }
     CIE_XYZ(const Color& c) : m_XYZ(dmnsn_XYZ_from_color(c.dmnsn())) { }
@@ -85,6 +88,7 @@ namespace Dimension
   class CIE_xyY
   {
   public:
+    CIE_xyY() { }
     CIE_xyY(double x, double y, double Y)
       { m_xyY.x = x; m_xyY.y = y; m_xyY.Y = Y; }
     CIE_xyY(const Color& c) : m_xyY(dmnsn_xyY_from_color(c.dmnsn())) { }
@@ -109,6 +113,7 @@ namespace Dimension
   class CIE_Lab
   {
   public:
+    CIE_Lab() { }
     CIE_Lab(double L, double a, double b)
       { m_Lab.L = L; m_Lab.a = a; m_Lab.b = b; }
     CIE_Lab(const Color& c, const CIE_XYZ& white = whitepoint)
@@ -134,6 +139,7 @@ namespace Dimension
   class CIE_Luv
   {
   public:
+    CIE_Luv() { }
     CIE_Luv(double L, double u, double v)
       { m_Luv.L = L; m_Luv.u = u; m_Luv.v = v; }
     CIE_Luv(const Color& c, const CIE_XYZ& white = whitepoint)
@@ -159,6 +165,7 @@ namespace Dimension
   class sRGB
   {
   public:
+    sRGB() { }
     sRGB(double R, double G, double B)
       { m_RGB.R = R; m_RGB.G = G; m_RGB.B = B; }
     sRGB(const Color& c) : m_RGB(dmnsn_sRGB_from_color(c.dmnsn())) { }
@@ -180,6 +187,8 @@ namespace Dimension
     dmnsn_sRGB m_RGB;
   };
 
+  // Color inline constructors
+
   inline Color::Color(const CIE_XYZ& XYZ)
     : m_color(dmnsn_color_from_XYZ(XYZ.dmnsn())) { }
 
@@ -194,6 +203,22 @@ namespace Dimension
 
   inline Color::Color(const sRGB& RGB)
     : m_color(dmnsn_color_from_sRGB(RGB.dmnsn())) { }
+
+  // Color operators
+
+  inline Color
+  operator+(const Color& lhs, const Color& rhs)
+  {
+    Color temp = lhs;
+    temp += rhs;
+    return temp;
+  }
+
+  inline double
+  operator-(const Color& lhs, const Color& rhs)
+  {
+    return dmnsn_color_difference(lhs.dmnsn(), rhs.dmnsn());
+  }
 }
 
 #endif /* DIMENSIONXX_COLOR_HPP */
diff --git a/libdimensionxx/dimensionxx/cookie.hpp b/libdimensionxx/dimensionxx/cookie.hpp
new file mode 100644
index 0000000..acb783d
--- /dev/null
+++ b/libdimensionxx/dimensionxx/cookie.hpp
@@ -0,0 +1,35 @@
+/*************************************************************************
+ * Copyright (C) 2008 Tavian Barnes <tavianator@gmail.com>               *
+ *                                                                       *
+ * This file is part of The Dimension Library.                           *
+ *                                                                       *
+ * The Dimension Library is free software; you can redistribute it and/  *
+ * or modify it under the terms of the GNU Lesser General Public License *
+ * as published by the Free Software Foundation; either version 3 of the *
+ * License, or (at your option) any later version.                       *
+ *                                                                       *
+ * The Dimension 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  *
+ * Lesser General Public License for more details.                       *
+ *                                                                       *
+ * You should have received a copy of the GNU Lesser General Public      *
+ * License along with this program.  If not, see                         *
+ * <http://www.gnu.org/licenses/>.                                       *
+ *************************************************************************/
+
+#ifndef DIMENSIONXX_COOKIE_HPP
+#define DIMENSIONXX_COOKIE_HPP
+
+#include <istream>
+#include <ostream>
+#include <cstdio>
+
+namespace Dimension
+{
+  std::FILE* fcookie(std::istream& istr);
+  std::FILE* fcookie(std::ostream& ostr);
+  std::FILE* fcookie(std::iostream& iostr);
+}
+
+#endif /* DIMENSIONXX_COOKIE_HPP */
diff --git a/libdimensionxx/dimensionxx/error.hpp b/libdimensionxx/dimensionxx/error.hpp
new file mode 100644
index 0000000..a6a4ca6
--- /dev/null
+++ b/libdimensionxx/dimensionxx/error.hpp
@@ -0,0 +1,30 @@
+/*************************************************************************
+ * Copyright (C) 2008 Tavian Barnes <tavianator@gmail.com>               *
+ *                                                                       *
+ * This file is part of The Dimension Library.                           *
+ *                                                                       *
+ * The Dimension Library is free software; you can redistribute it and/  *
+ * or modify it under the terms of the GNU Lesser General Public License *
+ * as published by the Free Software Foundation; either version 3 of the *
+ * License, or (at your option) any later version.                       *
+ *                                                                       *
+ * The Dimension 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  *
+ * Lesser General Public License for more details.                       *
+ *                                                                       *
+ * You should have received a copy of the GNU Lesser General Public      *
+ * License along with this program.  If not, see                         *
+ * <http://www.gnu.org/licenses/>.                                       *
+ *************************************************************************/
+
+#ifndef DIMENSIONXX_ERROR_HPP
+#define DIMENSIONXX_ERROR_HPP
+
+#include <dimension.h>
+
+namespace Dimension
+{
+}
+
+#endif /* DIMENSIONXX_ERROR_HPP */
diff --git a/libdimensionxx/dimensionxx/png.hpp b/libdimensionxx/dimensionxx/png.hpp
new file mode 100644
index 0000000..96ab2ca
--- /dev/null
+++ b/libdimensionxx/dimensionxx/png.hpp
@@ -0,0 +1,59 @@
+/*************************************************************************
+ * Copyright (C) 2008 Tavian Barnes <tavianator@gmail.com>               *
+ *                                                                       *
+ * This file is part of The Dimension Library.                           *
+ *                                                                       *
+ * The Dimension Library is free software; you can redistribute it and/  *
+ * or modify it under the terms of the GNU Lesser General Public License *
+ * as published by the Free Software Foundation; either version 3 of the *
+ * License, or (at your option) any later version.                       *
+ *                                                                       *
+ * The Dimension 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  *
+ * Lesser General Public License for more details.                       *
+ *                                                                       *
+ * You should have received a copy of the GNU Lesser General Public      *
+ * License along with this program.  If not, see                         *
+ * <http://www.gnu.org/licenses/>.                                       *
+ *************************************************************************/
+
+#ifndef DIMENSIONXX_PNG_HPP
+#define DIMENSIONXX_PNG_HPP
+
+#include <istream>
+#include <ostream>
+
+namespace Dimension
+{
+  class PNG_Canvas : public Canvas
+  {
+  public:
+    explicit PNG_Canvas(std::istream& istr)
+      : Canvas(), m_istr(&istr), m_ostr(0), m_written(false) { read(); }
+    PNG_Canvas(unsigned int x, unsigned int y, std::ostream& ostr)
+      : Canvas(x, y), m_istr(0), m_ostr(&ostr), m_written(false) { }
+    PNG_Canvas(std::istream& istr, std::ostream& ostr)
+      : Canvas(), m_istr(&istr), m_ostr(&ostr), m_written(false) { read(); }
+    virtual ~PNG_Canvas();
+
+    void write();
+
+  protected:
+    PNG_Canvas(std::ostream* ostr)
+      : Canvas(), m_istr(0), m_ostr(ostr), m_written(false) { }
+
+  private:
+    std::istream* m_istr;
+    std::ostream* m_ostr;
+    bool m_written;
+
+    void read();
+
+    // Copying prohibited
+    PNG_Canvas(const PNG_Canvas&);
+    PNG_Canvas& operator=(const PNG_Canvas&);
+  };
+}
+
+#endif /* DIMENSIONXX_PNG_HPP */
diff --git a/libdimensionxx/png.cpp b/libdimensionxx/png.cpp
new file mode 100644
index 0000000..14b8c4d
--- /dev/null
+++ b/libdimensionxx/png.cpp
@@ -0,0 +1,96 @@
+/*************************************************************************
+ * Copyright (C) 2008 Tavian Barnes <tavianator@gmail.com>               *
+ *                                                                       *
+ * This file is part of The Dimension Library.                           *
+ *                                                                       *
+ * The Dimension Library is free software; you can redistribute it and/  *
+ * or modify it under the terms of the GNU Lesser General Public License *
+ * as published by the Free Software Foundation; either version 3 of the *
+ * License, or (at your option) any later version.                       *
+ *                                                                       *
+ * The Dimension 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  *
+ * Lesser General Public License for more details.                       *
+ *                                                                       *
+ * You should have received a copy of the GNU Lesser General Public      *
+ * License along with this program.  If not, see                         *
+ * <http://www.gnu.org/licenses/>.                                       *
+ *************************************************************************/
+
+#include "dimensionxx.hpp"
+#include "../libdimension-png/dimension-png.h"
+
+namespace Dimension
+{
+  PNG_Canvas::~PNG_Canvas()
+  {
+    if (m_ostr && !m_written) {
+      try {
+        write();
+      } catch (...) {
+        dmnsn_error(DMNSN_SEVERITY_MEDIUM,
+                    "Writing canvas to PNG failed in PNG_Canvas destructor.");
+      }
+    }
+  }
+
+  void PNG_Canvas::write()
+  {
+    if (m_written) {
+      dmnsn_error(DMNSN_SEVERITY_MEDIUM,
+                  "Attempt to write canvas to PNG twice.");
+      return;
+    }
+
+    if (!m_ostr) {
+      dmnsn_error(DMNSN_SEVERITY_MEDIUM,
+                  "Attempt to write canvas to PNG without an output stream.");
+      return;
+    }      
+
+    FILE* file = fcookie(*m_ostr);
+    if (!file) {
+      dmnsn_error(DMNSN_SEVERITY_MEDIUM,
+                  "Couldn't create C++/C IO interface when writing canvas"
+                  " to PNG.");
+      return;
+    }      
+
+    if (dmnsn_png_write_canvas(m_canvas, file)) {
+      fclose(file);
+      dmnsn_error(DMNSN_SEVERITY_MEDIUM,
+                  "Writing canvas to PNG failed.");
+      return;
+    }
+
+    fclose(file);
+    m_written = true;
+  }
+
+  void PNG_Canvas::read()
+  {
+    if (!m_istr) {
+      dmnsn_error(DMNSN_SEVERITY_MEDIUM,
+                  "Attempt to read canvas from PNG without an input stream.");
+      return;
+    }      
+
+    FILE* file = fcookie(*m_istr);
+    if (!file) {
+      dmnsn_error(DMNSN_SEVERITY_MEDIUM,
+                  "Couldn't create C++/C IO interface when reading canvas"
+                  " from PNG.");
+      return;
+    }      
+
+    if (!(m_canvas = dmnsn_png_read_canvas(file))) {
+      fclose(file);
+      dmnsn_error(DMNSN_SEVERITY_MEDIUM,
+                  "Reading canvas from PNG failed.");
+      return;
+    }
+
+    fclose(file);
+  }
+}