[Cairo] Remove part of the dependency of FL/Fl.H on config.h.

To use Fl_Cairo_Window one did not only need to configure with --enable-cairo,
but also needed to #include <config.h> before #include <FL/Fl.H>.

This commit removes the smaller part of the dependency of the public header
file FL/Fl.H on config.h. This needs a better solution in FLTK 1.4.0.

The user still needs to define FLTK_HAVE_CAIRO _before_ #include <FL/Fl.H>.

Note: This is not compatible with fluid, since fluid _always_ includes
FL/Fl.H as the first statement in generated header files.

See also the discussion in fltk.general:

https://groups.google.com/d/msg/fltkgeneral/_C1OJhMLQl0/pHUFtz9SCwAJ

Note: also fixed a typo in src/drivers/X11/Fl_X11_Screen_Driver.cxx


git-svn-id: file:///fltk/svn/fltk/branches/branch-1.3-porting@11168 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

4 files changed, 47 insertions, 32 deletions

diff --git a/FL/Fl.H b/FL/Fl.H
index e1a2b97fa..5df4b4410 100644
--- a/FL/Fl.H
+++ b/FL/Fl.H
@@ -1295,19 +1295,19 @@ int main() {
   static int use_high_res_GL() { return use_high_res_GL_; }
 
 #ifdef FLTK_HAVE_CAIRO
-  /** \defgroup group_cairo Cairo support functions and classes 
+  /** \defgroup group_cairo Cairo Support Functions and Classes
       @{ 
   */
 public:
   // Cairo support API
   static cairo_t * cairo_make_current(Fl_Window* w);
-   /** when FLTK_HAVE_CAIRO is defined and cairo_autolink_context() is true, 
-      any current window dc is linked to a current context.
+   /** when FLTK_HAVE_CAIRO is defined and cairo_autolink_context() is true,
+      any current window dc is linked to a current cairo context.
       This is not the default, because it may not be necessary
       to add cairo support to all fltk supported windows.
       When you wish to associate a cairo context in this mode,
       you need to call explicitly in your draw() overridden method,
-      FL::cairo_make_current(Fl_Window*). This will create a cairo context
+      Fl::cairo_make_current(Fl_Window*). This will create a cairo context
       but only for this Window. 
       Still in custom cairo application it is possible to handle 
       completely this process automatically by setting \p alink to true.
diff --git a/FL/Fl_Cairo.H b/FL/Fl_Cairo.H
index 10e68392a..1994f0e5e 100644
--- a/FL/Fl_Cairo.H
+++ b/FL/Fl_Cairo.H
@@ -3,7 +3,7 @@
 //
 // Main header file for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2010 by Bill Spitzak and others.
+// Copyright 1998-2016 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -29,17 +29,7 @@
 
 # include <FL/Fl_Export.H>
 
-#if defined(USE_X11) // X11
-#  include <cairo-xlib.h>
-#elif defined(WIN32)
-#  include <cairo-win32.h>
-#elif defined(__APPLE_QUARTZ__) // PORTME: Cairo Support
-#  include <cairo-quartz.h>
-#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
+# include <cairo.h>
 
 /** 
    \addtogroup group_cairo
@@ -60,9 +50,16 @@ public:
     // access attributes
     cairo_t* cc() const {return cc_;}		 ///< Gets the current cairo context
     bool autolink() const {return autolink_;}	 ///< Gets the autolink option. See Fl::cairo_autolink_context(bool)
-    /** Sets the current cairo context, \p own indicates cc deletion is handle externally by user */
-    void cc(cairo_t* c, bool own=true)  {	 
-	if (cc_ && own_cc_) cairo_destroy(cc_); 
+    /** Sets the current cairo context.
+
+	\p own == \e true (the default) indicates that the cairo context \p c
+	will be deleted by FLTK internally when another cc is set later.
+
+	\p own == \e false indicates cc deletion is handled externally
+	by the user program.
+    */
+    void cc(cairo_t* c, bool own=true)  {
+	if (cc_ && own_cc_) cairo_destroy(cc_);
 	cc_=c;
 	if (!cc_) window_=0;
 	own_cc_=own;
@@ -76,7 +73,8 @@ public:
 private:
     cairo_t * cc_;	 // contains the unique autoupdated cairo context
     bool own_cc_;	 // indicates whether we must delete the cc, useful for internal cleanup
-    bool autolink_;	 // true by default, permits to prevent the automatic cairo mapping on fltk windows for custom cairo implementations
+    bool autolink_;	 // false by default, prevents the automatic cairo mapping on fltk windows
+			 // for custom cairo implementations.
     void* window_, *gc_; // for keeping track internally of last win+gc treated
 };
 
diff --git a/cairo/Fl_Cairo.cxx b/cairo/Fl_Cairo.cxx
index 1cdad67cb..ee767c9fd 100644
--- a/cairo/Fl_Cairo.cxx
+++ b/cairo/Fl_Cairo.cxx
@@ -3,7 +3,7 @@
 //
 // Main header file for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2010 by Bill Spitzak and others.
+// Copyright 1998-2016 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -26,8 +26,23 @@
 #include <Carbon/Carbon.h>
 #endif
 
+// Cairo is currently supported for the following platforms:
+// Win32, Apple Quartz, X11
+
+#if defined(USE_X11) // X11
+#  include <cairo-xlib.h>
+#elif defined(WIN32)
+#  include <cairo-win32.h>
+#elif defined(__APPLE_QUARTZ__) // PORTME: Cairo Support
+#  include <cairo-quartz.h>
+#elif defined(FL_PORTING)
+# pragma message "FL_PORTING: is the Cairo library available on this platform?"
+#else
+#  error Cairo is not supported on this platform.
+#endif
+
 // static Fl module initialization :
-Fl_Cairo_State Fl::cairo_state_;	///< contains all necesary info for current cairo context mapping
+Fl_Cairo_State Fl::cairo_state_;	///< contains all necessary info for current cairo context mapping
 
 
 // Fl cairo features implementation
@@ -39,22 +54,22 @@ void  Fl_Cairo_State::autolink(bool b)  {
   autolink_ = b;
 #else
   Fl::fatal("In Fl::autolink(bool) : Cairo autolink() feature is only "
-	   "available with the enable-cairoext configure option, now quitting.");
+	    "available with the enable-cairoext configure option, now quitting.");
 #endif
 }
 
 /** 
     Provides a corresponding cairo context for window \a wi.
-    This is needed in a draw() override if Fl::cairo_autolink_context() 
+    This is needed in a draw() override if Fl::cairo_autolink_context()
     returns false, which is the default.
-    The cairo_context() does not need to be freed as it is freed every time 
+    The cairo_context() does not need to be freed as it is freed every time
     a new cairo context is created. When the program terminates,
     a call to Fl::cairo_make_current(0) will destroy any residual context.
     \note A new cairo context is not always re-created when this method
-    is used. In particular, if the current graphical context and the current 
+    is used. In particular, if the current graphical context and the current
     window didn't change between two calls, the previous gc is internally kept,
     thus optimizing the drawing performances.
-    Also, after this call, Fl::cairo_gc() is adequately updated with this 
+    Also, after this call, Fl::cairo_cc() is adequately updated with this
     cairo  context.
     \note Only available when configure has the --enable-cairo option
     \return the valid cairo_t* cairo context associated to this window.
@@ -83,7 +98,8 @@ cairo_t * Fl::cairo_make_current(Fl_Window* wi) {
 
 /* 
     Creates transparently a cairo_surface_t object.
-    gc is an HDC context in  WIN32, a CGContext* in Quartz, a display on X11
+    gc is an HDC context in  WIN32, a CGContext* in Quartz, and
+    a display on X11 (not used on this platform)
  */
 
 static cairo_surface_t * cairo_create_surface(void * gc, int W, int H) {
@@ -99,8 +115,9 @@ static cairo_surface_t * cairo_create_surface(void * gc, int W, int H) {
 }
 
 /** 
-  Creates a cairo context from a \a gc only, get its window size or offscreen size if fl_window is null.
-   \note Only available when configure has the --enable-cairo option
+  Creates a cairo context from a \a gc only, gets its window size or
+  offscreen size if fl_window is null.
+  \note Only available when configure has the --enable-cairo option
 */
 cairo_t * Fl::cairo_make_current(void *gc) {
     int W=0,H=0;
@@ -127,7 +144,7 @@ cairo_t * Fl::cairo_make_current(void *gc) {
 #elif defined(WIN32)
     // we don't need any W,H for WIN32
 #else
-# error Cairo is not supported under this platform.
+# error Cairo is not supported on this platform.
 #endif
     if (!gc) {
 	Fl::cairo_cc(0);
diff --git a/src/drivers/X11/Fl_X11_Screen_Driver.cxx b/src/drivers/X11/Fl_X11_Screen_Driver.cxx
index f60d565d9..a2422c7b4 100644
--- a/src/drivers/X11/Fl_X11_Screen_Driver.cxx
+++ b/src/drivers/X11/Fl_X11_Screen_Driver.cxx
@@ -21,7 +21,7 @@
 #include "Fl_X11_Screen_Driver.h"
 #include <FL/Fl.H>
 #include <FL/x.H>
-#include <FL/fl_ask.h>
+#include <FL/fl_ask.H>
 
 #if HAVE_XINERAMA
 #  include <X11/extensions/Xinerama.h>