Improved the hierarchy of Fl_Device subclasses to allow separation of platform-specific devices.

This introduces multiple inheritance.

git-svn-id: file:///fltk/svn/fltk/branches/branch-1.3@7520 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

1 files changed, 83 insertions, 54 deletions

diff --git a/FL/Fl_Device.H b/FL/Fl_Device.H
index 8eaaa0c87..ad8506f1e 100644
--- a/FL/Fl_Device.H
+++ b/FL/Fl_Device.H
@@ -1,8 +1,8 @@
 //
 // "$Id$"
 //
-// Definition of classes Fl_Device, Fl_Display, Fl_Quartz_Display, Fl_GDI_Display,
-// and Fl_Xlib_Display for the Fast Light Tool Kit (FLTK).
+// Definition of classes Fl_Device, Fl_Display_Device, Fl_Graphics_Device
+// for the Fast Light Tool Kit (FLTK).
 //
 // Copyright 2010 by Bill Spitzak and others.
 //
@@ -26,7 +26,7 @@
 //     http://www.fltk.org/str.php
 //
 /** \file Fl_Device.H 
- \brief declaration of classes Fl_Device, Fl_Display.
+ \brief declaration of classes Fl_Device, Fl_Display_Device.
 */
 
 #ifndef Fl_Device_H
@@ -45,14 +45,12 @@
 #include <stdio.h>
 #endif
 
-class Fl_Widget;
 class Fl_Device;
-class Fl_Display;
-class Fl_Abstract_Printer;
+class Fl_Display_Device;
 /** \brief Points to the device that currently receives all graphics requests */
-FL_EXPORT extern Fl_Device *fl_device;
+extern Fl_Device *fl_device;
 /** \brief Points to the platform's display device */
-FL_EXPORT extern Fl_Display *fl_display_device;
+extern Fl_Display_Device *fl_display_device;
 
 /**
  signature of image generation callback function.
@@ -71,18 +69,18 @@ typedef void (*Fl_Draw_Image_Cb)(void* data,int x,int y,int w,uchar* buf);
  support all of FLTK drawing functions.
  <br> The preferred FLTK API for drawing operations is the function collection of the 
  \ref fl_drawings and \ref fl_attributes modules. 
- <br> Alternatively, member functions of the Fl_Device class can be called
+ <br> Alternatively, methods of the Fl_Device class can be called
  using the global variable Fl_Device * \ref fl_device that points at all time to the single device 
  (an instance of an Fl_Device subclass) that's currently receiving graphics requests:
  \code fl_device->rect(x, y, w, h); \endcode
- <br>Each member function of the Fl_Device class has the same effect and parameter list as the
+ <br>Each protected method of the Fl_Device class has the same effect as the
  function of the \ref fl_drawings and \ref fl_attributes modules which bears the same name
- prefixed with fl_ .
+ prefixed with fl_ and has the same parameter list.
   */
 class Fl_Device {
 protected:
   /** \brief The device type */
-  int type_; 
+  const char *type_; 
   /** \brief red color for background and/or mixing if device does not support masking or alpha */
   uchar bg_r_; 
   /** \brief green color for background and/or mixing if device does not support masking or alpha */
@@ -92,6 +90,7 @@ protected:
   friend class Fl_Pixmap;
   friend class Fl_Bitmap;
   friend class Fl_RGB_Image;
+  friend class Fl_PS_Device;
   friend void fl_rect(int x, int y, int w, int h);
   friend void fl_rectf(int x, int y, int w, int h);
   friend void fl_line_style(int style, int width, char* dashes);
@@ -239,73 +238,103 @@ protected:
   /** \brief see fl_draw_image_mono(Fl_Draw_Image_Cb cb, void* data, int X,int Y,int W,int H, int D). */
   virtual   void draw_image_mono(Fl_Draw_Image_Cb cb, void* data, int X,int Y,int W,int H, int D=1);
   // Image classes
-  virtual   void draw(Fl_RGB_Image * rgb,int XP, int YP, int WP, int HP, int cx, int cy);
-  virtual   void draw(Fl_Bitmap * bmp,int XP, int YP, int WP, int HP, int cx, int cy);  
-  virtual   void draw(Fl_Pixmap * pxm,int XP, int YP, int WP, int HP, int cx, int cy);
-  
-public:
-  /** 
-   @brief All implemented graphics output devices.
+  /** \brief Draws an Fl_RGB_Image object to the device. 
+   *
+   Specifies a bounding box for the image, with the origin (upper left-hand corner) of 
+   the image offset by the cx and cy arguments.
+   */
+  virtual   void draw(Fl_RGB_Image * rgb,int XP, int YP, int WP, int HP, int cx, int cy) {};
+  /** \brief Draws an Fl_Pixmap object to the device. 
+   *
+   Specifies a bounding box for the image, with the origin (upper left-hand corner) of 
+   the image offset by the cx and cy arguments.
    */
-  enum device_types { 
-    xlib_display = 0, /**< The X11 display. */
-    quartz_display,  /**< The Mac OS X display. */
-    gdi_display,  /**< The MSWindows display. */
-    gdi_printer = 256,  /**< The MSWindows printer. */
-    quartz_printer,  /**< The Mac OS X printer. */
-    postscript_device  /**< The PostScript device. */
-  };
+  virtual   void draw(Fl_Pixmap * pxm,int XP, int YP, int WP, int HP, int cx, int cy) {};
+  /** \brief Draws an Fl_Bitmap object to the device. 
+   *
+   Specifies a bounding box for the image, with the origin (upper left-hand corner) of 
+   the image offset by the cx and cy arguments.
+   */
+  virtual void draw(Fl_Bitmap *bm, int XP, int YP, int WP, int HP, int cx, int cy) {};
+    
+public:
+  /** A name that identifies each subclass of Fl_Device */
+  static const char *device_type;
   /** 
-   @brief An RTTI emulation of device classes. It returns values < 256 if it is a display device 
+   @brief An RTTI emulation of device classes. 
+   *
+   The type of an instance of an Fl_Device subclass can be checked with code such as:
+   \code
+   if ( fl_device->type() == Fl_Printer::device_type ) { ... }
+   \endcode
    */
-  inline int type() {return type_;};
+  inline const char *type() {return type_;};
   virtual Fl_Device *set_current(void);
-  
+
   virtual ~Fl_Device() {};
   static Fl_Device *current();
   
   /**
    @brief    Returns the platform's display device.
    */
-  static Fl_Display *display_device() { return fl_display_device; };
+  static Fl_Display_Device *display_device() { return fl_display_device; };
   
 };
-extern FL_EXPORT Fl_Device *fl_device;
 
-/**
- @brief A virtual class subclassed for OS-specific display graphics.
- */
-class Fl_Display : public Fl_Device {
-  friend class Fl_PSfile_Device;
+#if defined(__APPLE__) 
+// The Mac OS X-specific graphics class.
+class Fl_Graphics_Device : public Fl_Device {
+protected:
+  Fl_Graphics_Device() { type_ = device_type; };
+public:
+  static const char *device_type;
+  void draw(Fl_Pixmap *pxm, int XP, int YP, int WP, int HP, int cx, int cy);
+  void draw(Fl_Bitmap *pxm, int XP, int YP, int WP, int HP, int cx, int cy);
+  void draw(Fl_RGB_Image *img, int XP, int YP, int WP, int HP, int cx, int cy);
 };
+typedef Fl_Graphics_Device Fl_Quartz_Device;
 
-#if defined(__APPLE__) || defined(FL_DOXYGEN)
-/**
- @brief The Mac OS X-specific display graphics class.
- */
-class Fl_Quartz_Display : public Fl_Display {
+#elif defined(WIN32) 
+// The MSWindows-specific graphics class.
+class Fl_Graphics_Device : public Fl_Device {
+protected:
+  Fl_Graphics_Device() { type_ = device_type; };
 public:
-  Fl_Quartz_Display() { type_ = quartz_display; };
+  static const char *device_type;
+  void draw(Fl_Pixmap *pxm, int XP, int YP, int WP, int HP, int cx, int cy);
+  void draw(Fl_Bitmap *pxm, int XP, int YP, int WP, int HP, int cx, int cy);
+  void draw(Fl_RGB_Image *img, int XP, int YP, int WP, int HP, int cx, int cy);
 };
-#endif
-#if defined(WIN32) || defined(FL_DOXYGEN)
+typedef  Fl_Graphics_Device Fl_GDI_Device;
+
+#else
 /**
- @brief The MSWindows-specific display graphics class.
+ @brief A class representing OS-specific graphics system.
+ *
+ This class is also named Fl_Quartz_Device on Mac OS X, Fl_GDI_Device on MS-Win, Fl_Xlib_Device on X11.
+ A graphics system can be shared by various devices (e.g., display, printer, clipboard).
  */
-class Fl_GDI_Display : public Fl_Display {
+class Fl_Graphics_Device : public Fl_Device {
+protected:
+  Fl_Graphics_Device() { type_ = device_type; };
 public:
-  Fl_GDI_Display() { type_ = gdi_display; };
+  static const char *device_type;
+  void draw(Fl_Pixmap *pxm, int XP, int YP, int WP, int HP, int cx, int cy);
+  void draw(Fl_Bitmap *pxm, int XP, int YP, int WP, int HP, int cx, int cy);
+  void draw(Fl_RGB_Image *img, int XP, int YP, int WP, int HP, int cx, int cy);
 };
+typedef  Fl_Graphics_Device Fl_Xlib_Device;
 #endif
-#if !( defined(__APPLE__) || defined(WIN32)) || defined(FL_DOXYGEN)
+
 /**
- @brief The X11-specific display graphics class.
- */
-class Fl_Xlib_Display : public Fl_Display {
+ @brief The platform's display.
+*/
+class Fl_Display_Device : public Fl_Graphics_Device {
 public:
-  Fl_Xlib_Display() { type_ = xlib_display; };
+  static const char *device_type;
+  Fl_Display_Device() { type_ = device_type; };
 };
-#endif
+
 
 #endif // Fl_Device_H