// Filename: graphicsOutput.h
// Created by:  drose (06Feb04)
//
////////////////////////////////////////////////////////////////////
//
// PANDA 3D SOFTWARE
// Copyright (c) 2001, Disney Enterprises, Inc.  All rights reserved
//
// All use of this software is subject to the terms of the Panda 3d
// Software license.  You should have received a copy of this license
// along with this source code; you will also find a current copy of
// the license at http://www.panda3d.org/license.txt .
//
// To contact the maintainers of this program write to
// panda3d@yahoogroups.com .
//
////////////////////////////////////////////////////////////////////

#ifndef GRAPHICSOUTPUT_H
#define GRAPHICSOUTPUT_H

#include "pandabase.h"

#include "graphicsChannel.h"
#include "graphicsPipe.h"
#include "displayRegion.h"
#include "graphicsStateGuardian.h"
#include "clearableRegion.h"

#include "typedWritableReferenceCount.h"
#include "notify.h"
#include "pmutex.h"
#include "filename.h"
#include "pvector.h"

////////////////////////////////////////////////////////////////////
//       Class : GraphicsOutput
// Description : This is a base class for the various different
//               classes that represent the result of a frame of
//               rendering.  The most common kind of GraphicsOutput is
//               a GraphicsWindow, which is a real-time window on the
//               desktop, but other examples are GraphicsBuffer, which
//               is an offscreen buffer, and GraphicsTexture, which is
//               an offscreen texture that may be rendered into and
//               then applied to geometry.
//
//               The actual rendering, and anything associated with
//               the graphics context itself, is managed by the
//               associated GraphicsStateGuardian (which might output
//               to multiple GraphicsOutput objects).
//
//               GraphicsOutputs are not actually writable to bam
//               files, of course, but they may be passed as event
//               parameters, so they inherit from
//               TypedWritableReferenceCount instead of
//               TypedReferenceCount for that convenience.
////////////////////////////////////////////////////////////////////
class EXPCL_PANDA GraphicsOutput : public TypedWritableReferenceCount, public ClearableRegion {
protected:
  GraphicsOutput(GraphicsPipe *pipe, GraphicsStateGuardian *gsg);

private:
  GraphicsOutput(const GraphicsOutput &copy);
  void operator = (const GraphicsOutput &copy);

PUBLISHED:
  virtual ~GraphicsOutput();

  INLINE GraphicsStateGuardian *get_gsg() const;
  INLINE GraphicsPipe *get_pipe() const;

  INLINE int get_x_size() const;
  INLINE int get_y_size() const;
  INLINE bool has_size() const;
  INLINE bool is_valid() const;

  virtual bool is_active() const;

  GraphicsChannel *get_channel(int index);
  void remove_channel(int index);

  int get_max_channel_index() const;
  bool is_channel_defined(int index) const;

  int get_num_display_regions() const;
  DisplayRegion *get_display_region(int n) const;

  Filename take_screenshot(const string &prefix = "screenshot");
  bool take_screenshot(const Filename &filename);

public:
  // No need to publish these.
  PT(DisplayRegion) make_scratch_display_region(int x_size, int y_size) const;

public:
  // These are not intended to be called directly by the user.
  INLINE void win_display_regions_changed();

  virtual void request_open();
  virtual void request_close();
  virtual void set_close_now();

public:
  // It is an error to call any of the following methods from any
  // thread other than the draw thread.  These methods are normally
  // called by the GraphicsEngine.
  virtual bool begin_frame();
  void clear();
  virtual void end_frame();

  // This method is called in the draw thread prior to issuing any
  // drawing commands for the window.
  virtual void make_current();
  virtual void release_gsg();

  // These methods will be called within the app (main) thread.
  virtual void begin_flip();
  virtual void end_flip();

  // It is an error to call any of the following methods from any
  // thread other than the window thread.  These methods are normally
  // called by the GraphicsEngine.
  virtual void process_events();

protected:
  virtual void close_window();
  virtual bool open_window();
  virtual void reset_window(bool swapchain);

  void declare_channel(int index, GraphicsChannel *chan);
  
protected:
  PT(GraphicsStateGuardian) _gsg;
  PT(GraphicsPipe) _pipe;

private:
  INLINE void determine_display_regions() const;
  void do_determine_display_regions();

protected:
  Mutex _lock; 
  // protects _channels, _display_regions.

  typedef pvector< PT(GraphicsChannel) > Channels;
  Channels _channels;

  typedef pvector<DisplayRegion *> DisplayRegions;
  DisplayRegions _display_regions;
  bool _display_regions_stale;

protected:
  int _x_size;
  int _y_size;
  bool _has_size;
  bool _is_valid;
  
public:
  static TypeHandle get_class_type() {
    return _type_handle;
  }
  static void init_type() {
    TypedWritableReferenceCount::init_type();
    register_type(_type_handle, "GraphicsOutput",
                  TypedWritableReferenceCount::get_class_type());
  }
  virtual TypeHandle get_type() const {
    return get_class_type();
  }
  virtual TypeHandle force_init_type() {init_type(); return get_class_type();}

private:
  static TypeHandle _type_handle;

  friend class GraphicsPipe;
  friend class GraphicsEngine;
};

#include "graphicsOutput.I"

#endif /* GRAPHICSOUTPUT_H */