Updated platform specific #if's to report unimplemented code when compiling with FL_PORTING defined and WIN32 and __APPLE__ undefined>

git-svn-id: file:///fltk/svn/fltk/branches/branch-1.3-porting@10989 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

21 files changed, 220 insertions, 35 deletions

diff --git a/FL/Enumerations.H b/FL/Enumerations.H
index c73f67ee7..19da48ac5 100644
--- a/FL/Enumerations.H
+++ b/FL/Enumerations.H
@@ -577,6 +577,10 @@ enum Fl_When { // Fl_Widget::when():
 #ifdef __APPLE__
 #  define FL_COMMAND	FL_META		///< An alias for FL_CTRL on WIN32 and X11, or FL_META on MacOS X
 #  define FL_CONTROL 	FL_CTRL		///< An alias for FL_META on WIN32 and X11, or FL_CTRL on MacOS X
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: you need to define aliases for FL_COMMAND and FL_CONTROL"
+#  define FL_COMMAND	FL_CTRL
+#  define FL_CONTROL	FL_META
 #else
 #  define FL_COMMAND	FL_CTRL		///< An alias for FL_CTRL on WIN32 and X11, or FL_META on MacOS X
 #  define FL_CONTROL	FL_META		///< An alias for FL_META on WIN32 and X11, or FL_CTRL on MacOS X
diff --git a/FL/Fl.H b/FL/Fl.H
index 674873637..ebb40442d 100644
--- a/FL/Fl.H
+++ b/FL/Fl.H
@@ -50,6 +50,11 @@ struct Fl_Label;
 # else
 #  define FL_SOCKET int
 # endif
+#elif defined(__APPLE__)
+# define FL_SOCKET int
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: define a type for FL_SOCKET"
+# define FL_SOCKET int // default if not ported
 #else
 # define FL_SOCKET int
 #endif
@@ -158,6 +163,13 @@ public: // should be private!
 #ifdef __APPLE__
   static void reset_marked_text(); // resets marked text
   static void insertion_point_location(int x, int y, int height); // sets window coordinates & height of insertion point
+#elif defined(WIN32)
+  // not needed in WIN32
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: define a type for FL_SOCKET"
+  // no default implementation
+#else
+  // not needed in X11
 #endif
 #endif // FL_DOXYGEN
   
@@ -856,9 +868,18 @@ public:
   static void copy(const char* stuff, int len, int destination, const char *type);
   static void copy(const char* stuff, int len, int destination = 0);
 #endif
-  
-#if !(defined(__APPLE__) || defined(WIN32) || defined(FL_DOXYGEN))
-  static void copy_image(const unsigned char* data, int W, int H, int destination = 0); // platform dependent
+
+#if defined(__APPLE__)
+  // not needed
+#elif defined(WIN32)
+  // not needed
+#elif defined(FL_DOXYGEN)
+  // don't show in documentation
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: do you need to implement copy_image() ?"
+  // not implemented by default
+#else
+  static void copy_image(const unsigned char* data, int W, int H, int destination = 0); // X11 platform dependent
 #endif
   /**
   Pastes the data from the selection buffer (\p source is 0) or the clipboard 
diff --git a/FL/Fl_Bitmap.H b/FL/Fl_Bitmap.H
index a5a9b4590..75d84370f 100644
--- a/FL/Fl_Bitmap.H
+++ b/FL/Fl_Bitmap.H
@@ -48,6 +48,9 @@ public:
 #if defined(__APPLE__) || defined(WIN32)
   /** for internal use */
   void *id_;
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: define variables to hold a native bitmap in Fl_Bitmap"
+  unsigned id_; // default if not ported
 #else
   /** for internal use */
   unsigned id_;
diff --git a/FL/Fl_Cairo.H b/FL/Fl_Cairo.H
index e11440056..2637ecc28 100644
--- a/FL/Fl_Cairo.H
+++ b/FL/Fl_Cairo.H
@@ -29,15 +29,17 @@
 
 # include <FL/Fl_Export.H>
 
-# if defined(USE_X11) // X11
+#if defined(USE_X11) // X11
 #  include <cairo-xlib.h>
-# elif defined(WIN32)
+#elif defined(WIN32)
 #  include <cairo-win32.h>
-# elif defined(__APPLE_QUARTZ__)
+#elif defined(__APPLE_QUARTZ__)
 #  include <cairo-quartz.h>
-# else
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: is the Cairo library available on this platform?"
+#else
 #  error Cairo is not supported on that platform.
-# endif
+#endif
 
 /** 
    \addtogroup group_cairo
diff --git a/FL/Fl_Copy_Surface.H b/FL/Fl_Copy_Surface.H
index 6b3f50799..b598e8dd0 100644
--- a/FL/Fl_Copy_Surface.H
+++ b/FL/Fl_Copy_Surface.H
@@ -64,6 +64,9 @@ private:
 #elif defined(WIN32)
   HDC oldgc;
   HDC gc;
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: define variables to hold a native offscreen bitmap in Fl_Copy_Surface"
+  // no default implementation
 #else // Xlib
   Fl_Offscreen xid;
   Window oldwindow;
@@ -115,6 +118,10 @@ public:
   virtual ~Fl_GDI_Surface_();
 };
 
+#elif defined(FL_PORTING)
+
+# pragma message "FL_PORTING: define a drawing surface for your platform"
+
 #elif !defined(FL_DOXYGEN)
 
 /* Xlib class to implement translate()/untranslate() */
diff --git a/FL/Fl_Device.H b/FL/Fl_Device.H
index cd923c412..97266c391 100644
--- a/FL/Fl_Device.H
+++ b/FL/Fl_Device.H
@@ -57,6 +57,11 @@ typedef float COORD_T;
 typedef struct { float x; float y; } QPoint;
 #  define XPOINT QPoint
 extern float fl_quartz_line_width_;
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: define types for COORD_T and XPOINT"
+typedef int COORD_T; // default if not ported
+typedef struct { int x; int y; } QPoint;
+#  define XPOINT QPoint
 #else
 typedef short COORD_T;
 #  define XPOINT XPoint
@@ -131,6 +136,13 @@ private:
 #ifdef WIN32
   int numcount;
   int counts[20];
+#elif defined(__APPLE__)
+  // not needed
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: define variables for Fl_Graphics_Driver if needed."
+  // not needed
+#else
+  // not needed in X11
 #endif
   Fl_Font_Descriptor *font_descriptor_;
   void transformed_vertex0(COORD_T x, COORD_T y);
@@ -166,6 +178,12 @@ protected:
   friend void fl_draw(const char *str, int n, int x, int y);
 #ifdef __APPLE__
   friend void fl_draw(const char *str, int n, float x, float y);
+#elif defined(WIN32)
+  // not needed
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: add floating point text positioning if your platform supports it"
+#else 
+  // not needed
 #endif
   friend void fl_draw(int angle, const char *str, int n, int x, int y);
   friend void fl_rtl_draw(const char *str, int n, int x, int y);
@@ -251,6 +269,12 @@ protected:
   virtual void draw(const char *str, int n, int x, int y) {}
 #ifdef __APPLE__
   virtual void draw(const char *str, int n, float x, float y) { draw(str, n, (int)(x+0.5), (int)(y+0.5));}
+#elif defined(WIN32)
+  // not needed
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: add floating point text positioning if your platform supports it"
+#else
+  // not needed
 #endif
   /** \brief see fl_draw(int angle, const char *str, int n, int x, int y). */
   virtual void draw(int angle, const char *str, int n, int x, int y) {}
@@ -412,7 +436,9 @@ public:
   virtual ~Fl_Graphics_Driver() { if (p) free(p); }
 };
 
-#if defined(__APPLE__) || defined(FL_DOXYGEN)
+
+#if defined(__APPLE__)
+
 /**
  \brief The Mac OS X-specific graphics class.
  *
@@ -449,8 +475,9 @@ public:
 #endif
   void copy_offscreen(int x, int y, int w, int h, Fl_Offscreen pixmap, int srcx, int srcy);
 };
-#endif
-#if defined(WIN32) || defined(FL_DOXYGEN)
+
+#elif defined(WIN32) || defined(FL_DOXYGEN)
+
 /**
  \brief The MSWindows-specific graphics class.
  *
@@ -497,8 +524,13 @@ public:
   void draw(Fl_Bitmap *bm, int XP, int YP, int WP, int HP, int cx, int cy);
   int draw_scaled(Fl_Image *img, int XP, int YP, int WP, int HP);
 };
-#endif
-#if !(defined(__APPLE__) || defined(WIN32))
+
+#elif defined(FL_PORTING)
+
+# pragma message "FL_PORTING: define a native graphics driver Fl_xxx_Graphics_Driver"
+
+#else // X11
+
 /**
  \brief The Xlib-specific graphics class.
  *
@@ -531,6 +563,7 @@ public:
   void copy_offscreen_with_alpha(int x, int y, int w, int h, Fl_Offscreen pixmap, int srcx, int srcy);
 #endif
 };
+
 #endif
 
 /**
@@ -590,6 +623,10 @@ class FL_EXPORT Fl_Display_Device : public Fl_Surface_Device {
   friend class Fl_Graphics_Driver;
   static bool high_res_window_; //< true when drawing to a window of a retina display (Mac OS X only)
   static bool high_resolution() {return high_res_window_;}
+#elif defined(WIN32)
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: implement functions for extra high res drawing if your platform supports it"
+#else
 #endif
 public:
   static const char *class_id;
diff --git a/FL/Fl_Gl_Window.H b/FL/Fl_Gl_Window.H
index 44e2a8711..07d987f01 100644
--- a/FL/Fl_Gl_Window.H
+++ b/FL/Fl_Gl_Window.H
@@ -240,6 +240,10 @@ public:
    */
 #ifdef __APPLE__
   int pixels_per_unit();
+#elif defined(WIN32)
+  int pixels_per_unit() { return 1; }
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: define mutiple resolution OpenGL rendering if your platform supports it"
 #else
   int pixels_per_unit() { return 1; }
 #endif
diff --git a/FL/Fl_Image.H b/FL/Fl_Image.H
index 818e656ee..0396e6b48 100644
--- a/FL/Fl_Image.H
+++ b/FL/Fl_Image.H
@@ -208,6 +208,8 @@ public:
 #if defined(__APPLE__) || defined(WIN32)
   void *id_; // for internal use
   void *mask_; // for internal use (mask bitmap)
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: define variables to hold an RGB image and a mask for Fl_RGB_Image"
 #else
   unsigned id_; // for internal use
   unsigned mask_; // for internal use (mask bitmap)
diff --git a/FL/Fl_Image_Surface.H b/FL/Fl_Image_Surface.H
index 3414f72af..b3842dad5 100644
--- a/FL/Fl_Image_Surface.H
+++ b/FL/Fl_Image_Surface.H
@@ -55,6 +55,8 @@ private:
   Window _sw; 
   Fl_Surface_Device *_ss;
   int _savedc;
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: define variables to hold imaga data for Fl_Image_Surface"
 #else
   Fl_Surface_Device *previous;
   Window pre_window;
@@ -81,6 +83,10 @@ public:
   void untranslate();
   virtual ~Fl_Quartz_Flipped_Surface_() {};
 };
+#elif defined(WIN32)
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: define a helper class for Fl_Image_Surface if needed"
+#else
 #endif 
 
 #endif // Fl_Image_Surface_H
diff --git a/FL/Fl_Native_File_Chooser.H b/FL/Fl_Native_File_Chooser.H
index 1a9912a29..135f0399c 100644
--- a/FL/Fl_Native_File_Chooser.H
+++ b/FL/Fl_Native_File_Chooser.H
@@ -25,6 +25,7 @@
 
 // Use Windows' chooser
 #ifdef WIN32
+
 // #define _WIN32_WINNT	0x0501	// needed for OPENFILENAME's 'FlagsEx'
 #if defined(FL_LIBRARY) || FLTK_ABI_VERSION < 10304
 #  include <windows.h>
@@ -36,18 +37,21 @@ typedef BROWSEINFOW fl_BROWSEINFOW;
 typedef void fl_OPENFILENAMEW;
 typedef void fl_BROWSEINFOW;
 #endif
-#endif
+#  include <FL/filename.H>	// FL_EXPORT
 
 // Use Apple's chooser
-#ifdef __APPLE__
+#elif defined(__APPLE__)
 #  define MAXFILTERS	80
-#endif
+#  include <FL/filename.H>	// FL_EXPORT
+
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: define a file chooser if one is available on your platform"
+#  include <FL/Fl_File_Chooser.H> // default to FLTK file chooser if none id ported
 
 // All else falls back to FLTK's own chooser
-#if ! defined(__APPLE__) && !defined(WIN32)
-#  include <FL/Fl_File_Chooser.H>
 #else
-#  include <FL/filename.H>	// FL_EXPORT
+#  include <FL/Fl_File_Chooser.H>
+
 #endif
 
 class Fl_FLTK_File_Chooser;
@@ -192,9 +196,8 @@ private:
   void parse_filter(const char *);
   void clear_filters();
   void add_filter(const char *, const char *);
-#endif
 
-#ifdef __APPLE__
+#elif defined(__APPLE__)
 private:
   int             _btype;		// kind-of browser to show()
   int             _options;		// general options
@@ -230,9 +233,12 @@ private:
   void parse_filter(const char *from);
   int post();
   int runmodal();
-#endif
 
-#if ! defined(__APPLE__) && !defined(WIN32)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: define member variables for file chooser if one is available on your platform"
+
+#else
+
 private:
 #if FLTK_ABI_VERSION <= 10302
   int   _btype;			// kind-of browser to show()
@@ -254,7 +260,8 @@ private:
 #endif
 };
 
-#if !defined(__APPLE__) && !defined(WIN32)
+
+#if !defined(__APPLE__) && !defined(WIN32) && !defined(FL_PORTING)
 class FL_EXPORT Fl_FLTK_File_Chooser {
   friend class Fl_Native_File_Chooser;
 protected:
diff --git a/FL/Fl_Paged_Device.H b/FL/Fl_Paged_Device.H
index 5869018b5..9dd6b7d8d 100644
--- a/FL/Fl_Paged_Device.H
+++ b/FL/Fl_Paged_Device.H
@@ -36,7 +36,14 @@
  or Fl_PostScript_File_Device instead.
  */
 class FL_EXPORT Fl_Paged_Device : public Fl_Surface_Device {
-#ifndef __APPLE__
+#ifdef __APPLE__
+  // not needed
+#elif defined(WIN32)
+  friend class Fl_Copy_Surface;
+  void draw_decorated_window(Fl_Window *win, int x_offset, int y_offset, Fl_Surface_Device *toset);
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: define member variables to support Fl_Copy_Surface in Fl_Paged_Device"
+#else // X11
   friend class Fl_Copy_Surface;
   void draw_decorated_window(Fl_Window *win, int x_offset, int y_offset, Fl_Surface_Device *toset);
 #endif
diff --git a/FL/Fl_Pixmap.H b/FL/Fl_Pixmap.H
index 6f93da7e8..4be6ee28c 100644
--- a/FL/Fl_Pixmap.H
+++ b/FL/Fl_Pixmap.H
@@ -64,10 +64,13 @@ class FL_EXPORT Fl_Pixmap : public Fl_Image {
   static // a static member is needed for ABI compatibility
 #endif
   UINT pixmap_bg_color; // RGB color used for pixmap background
-#endif // WIN32
-#if defined(__APPLE__) || defined(WIN32)
   void *id_; // for internal use
   void *mask_; // for internal use (mask bitmap)
+#elif defined(__APPLE__)
+  void *id_; // for internal use
+  void *mask_; // for internal use (mask bitmap)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: define member variables to store an RGB image and a mask for Fl_Pixmap"
 #else
   unsigned id_; // for internal use
   unsigned mask_; // for internal use (mask bitmap)
diff --git a/FL/Fl_PostScript.H b/FL/Fl_PostScript.H
index c635e88ef..1c048391f 100644
--- a/FL/Fl_PostScript.H
+++ b/FL/Fl_PostScript.H
@@ -201,6 +201,12 @@ class Clip {
   void draw(const char* s, int nBytes, int x, int y) {transformed_draw(s,nBytes,x,y); };
 #ifdef __APPLE__
   void draw(const char* s, int nBytes, float x, float y) {transformed_draw(s,nBytes,x,y); };
+#elif defined(WIN32)
+  // not needed
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: define floating point position text drawing if you have it"
+#else // X11
+      // not needed
 #endif
   void draw(int angle, const char *str, int n, int x, int y);
   void rtl_draw(const char* s, int n, int x, int y);
@@ -226,6 +232,12 @@ class Clip {
 class FL_EXPORT Fl_PostScript_File_Device : public Fl_Paged_Device {
 #ifdef __APPLE__
   CGContextRef gc;
+#elif defined(WIN32)
+  // not needed
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: define storage for your graphics context in Fl_Postscript_File_Device if needed"
+#else // X11
+  // not needed
 #endif
 protected:
   Fl_PostScript_Graphics_Driver *driver();
@@ -252,6 +264,12 @@ public:
   void end_job(void);
 #ifdef __APPLE__
   void set_current() { fl_gc = gc; Fl_Paged_Device::set_current(); }
+#elif defined(WIN32)
+  // not needed
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: set access to your graphics context in Fl_Postscript_File_Device if needed"
+#else // X11
+      // not needed
 #endif
   
   static const char *file_chooser_title; 
diff --git a/FL/Fl_Printer.H b/FL/Fl_Printer.H
index 7ff255f24..ffea61dc1 100644
--- a/FL/Fl_Printer.H
+++ b/FL/Fl_Printer.H
@@ -30,10 +30,14 @@
 #include <FL/Fl_RGB_Image.H>
 #include <FL/Fl_Bitmap.H>
 #include <stdio.h>
-#if !(defined(__APPLE__) || defined(WIN32))
-#include <FL/Fl_PostScript.H>
-#elif defined(WIN32)
+#ifdef WIN32
 #include <commdlg.h>
+#elif defined(__APPLE__)
+  // not needed
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: include files needed for printing support"
+#else // X11
+#include <FL/Fl_PostScript.H>
 #endif
 
 #if defined(__APPLE__) || defined(WIN32) || defined(FL_DOXYGEN)
@@ -91,9 +95,12 @@ public:
   ~Fl_System_Printer(void);
 }; // class Fl_System_Printer
 
-#endif
-  
-#if !(defined(__APPLE__) || defined(WIN32) )
+#elif defined(FL_PORTING)
+
+# pragma message "FL_PORTING: define your own Fl_xxx_Printer class"
+
+#else 
+
 /**
  Print support under Unix/Linux.
  
@@ -224,6 +231,8 @@ public:
 private:
 #if defined(WIN32) || defined(__APPLE__)
   Fl_System_Printer *printer;
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: instantiate your own Fl_xxx_Printer here"
 #else
   Fl_PostScript_Printer *printer;
 #endif
diff --git a/FL/Fl_Sys_Menu_Bar.H b/FL/Fl_Sys_Menu_Bar.H
index a3cf521d9..da80e8913 100644
--- a/FL/Fl_Sys_Menu_Bar.H
+++ b/FL/Fl_Sys_Menu_Bar.H
@@ -93,6 +93,14 @@ public:
   void setonly (Fl_Menu_Item *item) { Fl_Menu_::setonly(item); update(); }
 };
 
+#elif defined(WIN32)
+
+typedef Fl_Menu_Bar Fl_Sys_Menu_Bar;
+
+#elif defined(FL_PORTING)
+
+# pragma message "FL_PORTING: define your own system menu class"
+
 #else
 
 typedef Fl_Menu_Bar Fl_Sys_Menu_Bar;
diff --git a/FL/Fl_Tooltip.H b/FL/Fl_Tooltip.H
index 300c921dd..f3aef8b34 100644
--- a/FL/Fl_Tooltip.H
+++ b/FL/Fl_Tooltip.H
@@ -100,6 +100,12 @@ public:
 #ifdef __APPLE__
   // the unique tooltip window
   static Fl_Window* current_window(void);
+#elif defined(WIN32)
+  // not needed
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: do we need to remember the tooltip parent window?"
+#else // X11
+  // not needed
 #endif
 
   // These should not be public, but Fl_Widget::tooltip() needs them...
diff --git a/FL/Fl_Window.H b/FL/Fl_Window.H
index f84ab1c9a..0a69a4c13 100644
--- a/FL/Fl_Window.H
+++ b/FL/Fl_Window.H
@@ -103,6 +103,12 @@ class FL_EXPORT Fl_Window : public Fl_Group {
 #ifdef WIN32
     HICON big_icon;
     HICON small_icon;
+#elif defined(__APPLE__)
+    // not needed
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: define storage for per-window icons here if needed"
+#else // X11
+      // not needed
 #endif
   };
 
@@ -129,6 +135,12 @@ protected:
 #if defined(__APPLE__)
     typedef struct CGImage* CGImageRef;
     CGImageRef mask;
+#elif defined(WIN32)
+    // not needed
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: define storage for a window mask here if needed"
+#else // X11
+      // not needed
 #endif
     Fl_Bitmap *todelete_; ///<  auxiliary bitmap image
   };
@@ -147,7 +159,10 @@ public:
    \see void shape(const Fl_Image* img)
    */
   inline void shape(const Fl_Image& b) { shape(&b); }
-#if ! (defined(WIN32) || defined(__APPLE__) || defined(FL_DOXYGEN))
+#if defined(WIN32) || defined(__APPLE__) || defined(FL_DOXYGEN)
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: do you need a combine_mask() function in Fl_Window?"
+#else // X11
   void combine_mask(void);
 #endif
 private:
@@ -471,6 +486,12 @@ public:
 #ifdef WIN32
   static void default_icons(HICON big_icon, HICON small_icon);
   void icons(HICON big_icon, HICON small_icon);
+#elif defined(__APPLE__)
+  // not needed
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: define functions to handle window icons here if needed"
+#else // X11
+      // not needed
 #endif
 
   /* for legacy compatibility */
diff --git a/FL/filename.H b/FL/filename.H
index f5c87bc6a..1d3ca6249 100644
--- a/FL/filename.H
+++ b/FL/filename.H
@@ -81,6 +81,9 @@ struct dirent {char d_name[1];};
 #    include <sys/types.h>
 #    include <direct.h>
 
+#  elif defined(FL_PORTING)
+#    pragma message "FL_PORTING: insert the equivalent to dirent.h on your system"
+     struct dirent {char d_name[1];}; // default if not ported
 #  else
 /*
  * WARNING: on some systems (very few nowadays?) <dirent.h> may not exist.
diff --git a/FL/fl_utf8.h b/FL/fl_utf8.h
index 7ac79e1f5..b19f2a962 100644
--- a/FL/fl_utf8.h
+++ b/FL/fl_utf8.h
@@ -57,6 +57,9 @@
 #  include <wchar.h>
 #  include <sys/stat.h>
 #  define xchar wchar_t
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: include utf8 support files and define utf8 types"
+#  define xchar unsigned short
 #else /* X11 */
 #  include <sys/types.h>
 #  include <sys/stat.h>
@@ -158,6 +161,12 @@ FL_EXPORT char *fl_utf8_to_locale(const char *s, int len, unsigned int codepage)
 
 /* OD: Attempt to convert a string in the current locale to UTF-8 */
 FL_EXPORT char *fl_locale_to_utf8(const char *s, int len, unsigned int codepage);
+#elif defined(__APPLE__)
+  // not needed
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: do you want to be able to convert from a local charset to utf8?"
+#else // X11
+  // not needed
 #endif
 
 /*****************************************************************************
diff --git a/FL/gl.h b/FL/gl.h
index bb0881df1..2d2fdc274 100644
--- a/FL/gl.h
+++ b/FL/gl.h
@@ -92,6 +92,12 @@ FL_EXPORT void gl_measure(const char*, int& x, int& y);
 #ifdef __APPLE__
 extern FL_EXPORT void gl_texture_pile_height(int max);
 extern FL_EXPORT int gl_texture_pile_height();
+#elif defined(WIN32)
+  // not needed
+#elif defined(FL_PORTING)
+#  pragma message "FL_PORTING: define functions to control OpenGL texture pile height if supported"
+#else // X11
+  // not needed
 #endif
 
 FL_EXPORT void gl_draw_image(const uchar *, int x,int y,int w,int h, int d=3, int ld=0);
diff --git a/FL/x.H b/FL/x.H
index a15b8acd4..d2b25f954 100644
--- a/FL/x.H
+++ b/FL/x.H
@@ -30,7 +30,9 @@
 #    include "win32.H"
 #  elif defined(__APPLE__)
 #    include "mac.H"
-#  else
+#  elif defined(FL_PORTING)
+#    pragma message "FL_PORTING: write  a header file based on this file, win32.H, or mac.H to define the FLTK core internals"
+#  else // X11
 #    if defined(_ABIN32) || defined(_ABI64) // fix for broken SGI Irix X .h files
 #      pragma set woff 3322
 #    endif