/**
 * PANDA 3D SOFTWARE
 * Copyright (c) Carnegie Mellon University.  All rights reserved.
 *
 * All use of this software is subject to the terms of the revised BSD
 * license.  You should have received a copy of this license along
 * with this source code in a file named "LICENSE."
 *
 * @file displayRegion.h
 * @author mike
 * @date 1997-01-09
 */

#ifndef DISPLAYREGION_H
#define DISPLAYREGION_H

#include "pandabase.h"

#include "typedReferenceCount.h"
#include "drawableRegion.h"
#include "referenceCount.h"
#include "nodePath.h"
#include "cullResult.h"
#include "sceneSetup.h"
#include "pointerTo.h"
#include "cycleData.h"
#include "cycleDataLockedReader.h"
#include "cycleDataReader.h"
#include "cycleDataWriter.h"
#include "cycleDataStageWriter.h"
#include "pipelineCycler.h"
#include "config_display.h"
#include "lens.h"
#include "deletedChain.h"
#include "plist.h"
#include "pStatCollector.h"
#include "cullTraverser.h"
#include "callbackObject.h"
#include "luse.h"
#include "epvector.h"

class GraphicsOutput;
class GraphicsPipe;
class CullHandler;
class Camera;
class PNMImage;
class CullTraverser;

/**
 * A rectangular subregion within a window for rendering into.  Typically,
 * there is one DisplayRegion that covers the whole window, but you may also
 * create smaller DisplayRegions for having different regions within the
 * window that represent different scenes.  You may also stack up
 * DisplayRegions like panes of glass, usually for layering 2-d interfaces on
 * top of a 3-d scene.
 */
class EXPCL_PANDA_DISPLAY DisplayRegion : public TypedReferenceCount, public DrawableRegion {
protected:
  DisplayRegion(GraphicsOutput *window, const LVecBase4 &dimensions);
  DisplayRegion(const DisplayRegion &copy) = delete;
  void operator = (const DisplayRegion &copy) = delete;

public:
  virtual ~DisplayRegion();
  void cleanup();

  INLINE bool operator < (const DisplayRegion &other) const;

PUBLISHED:
  INLINE int get_num_regions() const;
  INLINE void set_num_regions(int i);
  INLINE void get_dimensions(PN_stdfloat &l, PN_stdfloat &r, PN_stdfloat &b, PN_stdfloat &t) const;
  INLINE void get_dimensions(int i, PN_stdfloat &l, PN_stdfloat &r, PN_stdfloat &b, PN_stdfloat &t) const;
  INLINE LVecBase4 get_dimensions(int i = 0) const;
  INLINE PN_stdfloat get_left(int i = 0) const;
  INLINE PN_stdfloat get_right(int i = 0) const;
  INLINE PN_stdfloat get_bottom(int i = 0) const;
  INLINE PN_stdfloat get_top(int i = 0) const;
  INLINE void set_dimensions(PN_stdfloat l, PN_stdfloat r, PN_stdfloat b, PN_stdfloat t);
  INLINE void set_dimensions(int i, PN_stdfloat l, PN_stdfloat r, PN_stdfloat b, PN_stdfloat t);
  INLINE void set_dimensions(const LVecBase4 &dimensions);
  virtual void set_dimensions(int i, const LVecBase4 &dimensions);
  MAKE_PROPERTY(dimensions, get_dimensions, set_dimensions);

  INLINE GraphicsOutput *get_window() const;
  GraphicsPipe *get_pipe() const;
  virtual bool is_stereo() const;
  MAKE_PROPERTY(window, get_window);
  MAKE_PROPERTY(pipe, get_pipe);
  MAKE_PROPERTY(stereo, is_stereo);

  virtual void set_camera(const NodePath &camera);
  INLINE NodePath get_camera(Thread *current_thread = Thread::get_current_thread()) const;
  MAKE_PROPERTY(camera, get_camera, set_camera);

  virtual void set_active(bool active);
  INLINE bool is_active() const;
  MAKE_PROPERTY(active, is_active, set_active);

  virtual void set_sort(int sort);
  INLINE int get_sort() const;
  MAKE_PROPERTY(sort, get_sort, set_sort);

  virtual void set_stereo_channel(Lens::StereoChannel stereo_channel);
  INLINE Lens::StereoChannel get_stereo_channel() const;
  MAKE_PROPERTY(stereo_channel, get_stereo_channel, set_stereo_channel);

  virtual void set_tex_view_offset(int tex_view_offset);
  INLINE int get_tex_view_offset() const;
  MAKE_PROPERTY(tex_view_offset, get_tex_view_offset, set_tex_view_offset);

  virtual void set_incomplete_render(bool incomplete_render);
  INLINE bool get_incomplete_render() const;
  MAKE_PROPERTY(incomplete_render, get_incomplete_render, set_incomplete_render);

  virtual void set_texture_reload_priority(int texture_reload_priority);
  INLINE int get_texture_reload_priority() const;
  MAKE_PROPERTY(texture_reload_priority, get_texture_reload_priority,
                                         set_texture_reload_priority);

  void set_lens_index(int index);
  INLINE int get_lens_index() const;
  MAKE_PROPERTY(lens_index, get_lens_index, set_lens_index);

  virtual void set_cull_traverser(CullTraverser *trav);
  CullTraverser *get_cull_traverser();
  MAKE_PROPERTY(cull_traverser, get_cull_traverser, set_cull_traverser);

  INLINE void set_cube_map_index(int cube_map_index);
  virtual void set_target_tex_page(int page);
  INLINE int get_target_tex_page() const;
  MAKE_PROPERTY(target_tex_page, get_target_tex_page, set_target_tex_page);

  INLINE void set_scissor_enabled(bool scissor_enabled);
  INLINE bool get_scissor_enabled() const;
  MAKE_PROPERTY(scissor_enabled, get_scissor_enabled, set_scissor_enabled);

  INLINE void set_cull_callback(CallbackObject *object);
  INLINE void clear_cull_callback();
  INLINE CallbackObject *get_cull_callback() const;
  MAKE_PROPERTY(cull_callback, get_cull_callback, set_cull_callback);

  INLINE void set_draw_callback(CallbackObject *object);
  INLINE void clear_draw_callback();
  INLINE CallbackObject *get_draw_callback() const;
  MAKE_PROPERTY(draw_callback, get_draw_callback, set_draw_callback);

  INLINE int get_pixel_width(int i = 0) const;
  INLINE int get_pixel_height(int i = 0) const;
  INLINE LVecBase2i get_pixel_size(int i = 0) const;
  MAKE_PROPERTY(pixel_size, get_pixel_size);

  virtual void output(std::ostream &out) const;

  static Filename make_screenshot_filename(
    const std::string &prefix = "screenshot");
  Filename save_screenshot_default(const std::string &prefix = "screenshot");
  bool save_screenshot(
    const Filename &filename, const std::string &image_comment = "");
  bool get_screenshot(PNMImage &image);
  PT(Texture) get_screenshot();

  virtual PT(PandaNode) make_cull_result_graph();

public:
  void compute_pixels();
  void compute_pixels_all_stages();
  void compute_pixels(int x_size, int y_size);
  void compute_pixels_all_stages(int x_size, int y_size);
  INLINE void get_pixels(int &pl, int &pr, int &pb, int &pt) const;
  INLINE void get_pixels(int i, int &pl, int &pr, int &pb, int &pt) const;
  INLINE void get_region_pixels(int &xo, int &yo, int &w, int &h) const;
  INLINE void get_region_pixels(int i, int &xo, int &yo, int &w, int &h) const;
  INLINE void get_region_pixels_i(int &xo, int &yo, int &w, int &h) const;
  INLINE void get_region_pixels_i(int i, int &xo, int &yo, int &w, int &h) const;

  virtual bool supports_pixel_zoom() const;

  INLINE void set_cull_result(PT(CullResult) cull_result, PT(SceneSetup) scene_setup,
                              Thread *current_thread);
  INLINE CullResult *get_cull_result(Thread *current_thread) const;
  INLINE SceneSetup *get_scene_setup(Thread *current_thread) const;

  INLINE PStatCollector &get_cull_region_pcollector();
  INLINE PStatCollector &get_draw_region_pcollector();

  INLINE const std::string &get_debug_name() const;

  struct Region {
    INLINE Region();

    LVecBase4 _dimensions;  // left, right, bottom, top
    LVecBase4i _pixels;
    LVecBase4i _pixels_i;
  };
  typedef epvector<Region> Regions;

private:
  class CData;

  void win_display_regions_changed();
  void do_compute_pixels(int i, int x_size, int y_size, CData *cdata);
  void set_active_index(int index);

protected:
  virtual void do_cull(CullHandler *cull_handler, SceneSetup *scene_setup,
                       GraphicsStateGuardian *gsg, Thread *current_thread);

protected:
  // The associated window is a permanent property of the DisplayRegion.  It
  // doesn't need to be cycled.
  GraphicsOutput *_window;

  bool _incomplete_render;
  int _texture_reload_priority;

  // Ditto for the cull traverser.
  PT(CullTraverser) _trav;

private:
  // This is the data that is associated with the DisplayRegion that needs to
  // be cycled every frame, but represents the parameters as specified by the
  // user, and which probably will not change that often.
  class EXPCL_PANDA_DISPLAY CData : public CycleData {
  public:
    CData();
    CData(const CData &copy);

    virtual CycleData *make_copy() const;
    virtual TypeHandle get_parent_type() const {
      return DisplayRegion::get_class_type();
    }

    Regions _regions;

    int _lens_index; // index into which lens of a camera is associated with this display region.  0 is default

    NodePath _camera;
    Camera *_camera_node;

    bool _active;
    int _sort;
    Lens::StereoChannel _stereo_channel;
    int _tex_view_offset;
    int _target_tex_page;
    bool _scissor_enabled;

    PT(CallbackObject) _cull_callback;
    PT(CallbackObject) _draw_callback;
  };

  PipelineCycler<CData> _cycler;
  typedef CycleDataLockedReader<CData> CDLockedReader;
  typedef CycleDataReader<CData> CDReader;
  typedef CycleDataWriter<CData> CDWriter;
  typedef CycleDataStageWriter<CData> CDStageWriter;

  // This is a special cycler created to hold the results from the cull
  // traversal, for (a) the draw traversal, and (b) the next frame's cull
  // traversal.  It needs to be cycled, but it gets its own cycler because it
  // will certainly change every frame, so we don't need to lump all the heavy
  // data above in with this lightweight cycler.
  class EXPCL_PANDA_DISPLAY CDataCull : public CycleData {
  public:
    CDataCull();
    CDataCull(const CDataCull &copy);

    virtual CycleData *make_copy() const;
    virtual TypeHandle get_parent_type() const {
      return DisplayRegion::get_class_type();
    }

    PT(CullResult) _cull_result;
    PT(SceneSetup) _scene_setup;
  };
  PipelineCycler<CDataCull> _cycler_cull;
  typedef CycleDataReader<CDataCull> CDCullReader;
  typedef CycleDataWriter<CDataCull> CDCullWriter;

  PStatCollector _cull_region_pcollector;
  PStatCollector _draw_region_pcollector;
  std::string _debug_name;

public:
  static TypeHandle get_class_type() {
    return _type_handle;
  }
  static void init_type() {
    TypedReferenceCount::init_type();
    register_type(_type_handle, "DisplayRegion",
                  TypedReferenceCount::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 GraphicsEngine;
  friend class GraphicsOutput;
  friend class DisplayRegionCullCallbackData;
  friend class DisplayRegionPipelineReader;
};

/**
 * Encapsulates the data from a DisplayRegion, pre-fetched for one stage of
 * the pipeline.
 */
class EXPCL_PANDA_DISPLAY DisplayRegionPipelineReader {
public:
  INLINE DisplayRegionPipelineReader(DisplayRegion *object, Thread *current_thread);
  DisplayRegionPipelineReader(const DisplayRegionPipelineReader &copy) = delete;
  void operator = (const DisplayRegionPipelineReader &copy) = delete;

public:
  INLINE ~DisplayRegionPipelineReader();
  ALLOC_DELETED_CHAIN(DisplayRegionPipelineReader);

  INLINE DisplayRegion *get_object() const;
  INLINE Thread *get_current_thread() const;

  INLINE bool is_any_clear_active() const;

  INLINE int get_num_regions() const;
  INLINE void get_dimensions(PN_stdfloat &l, PN_stdfloat &r, PN_stdfloat &b, PN_stdfloat &t) const;
  INLINE void get_dimensions(int i, PN_stdfloat &l, PN_stdfloat &r, PN_stdfloat &b, PN_stdfloat &t) const;
  INLINE const LVecBase4 &get_dimensions(int i = 0) const;
  INLINE PN_stdfloat get_left(int i = 0) const;
  INLINE PN_stdfloat get_right(int i = 0) const;
  INLINE PN_stdfloat get_bottom(int i = 0) const;
  INLINE PN_stdfloat get_top(int i = 0) const;

  INLINE GraphicsOutput *get_window() const;
  GraphicsPipe *get_pipe() const;

  INLINE NodePath get_camera() const;
  INLINE bool is_active() const;
  INLINE int get_sort() const;
  INLINE Lens::StereoChannel get_stereo_channel() const;
  INLINE int get_tex_view_offset();
  INLINE bool get_clear_depth_between_eyes() const;
  INLINE int get_target_tex_page() const;
  INLINE bool get_scissor_enabled() const;
  INLINE CallbackObject *get_draw_callback() const;

  INLINE void get_pixels(int &pl, int &pr, int &pb, int &pt) const;
  INLINE void get_pixels(int i, int &pl, int &pr, int &pb, int &pt) const;
  INLINE void get_region_pixels(int &xo, int &yo, int &w, int &h) const;
  INLINE void get_region_pixels(int i, int &xo, int &yo, int &w, int &h) const;
  INLINE void get_region_pixels_i(int &xo, int &yo, int &w, int &h) const;
  INLINE void get_region_pixels_i(int i, int &xo, int &yo, int &w, int &h) const;

  INLINE int get_pixel_width(int i = 0) const;
  INLINE int get_pixel_height(int i = 0) const;

  INLINE int get_lens_index() const;

private:
  DisplayRegion *_object;
  Thread *_current_thread;
  const DisplayRegion::CData *_cdata;

public:
  static TypeHandle get_class_type() {
    return _type_handle;
  }
  static void init_type() {
    register_type(_type_handle, "DisplayRegionPipelineReader");
  }

private:
  static TypeHandle _type_handle;
};

INLINE std::ostream &operator << (std::ostream &out, const DisplayRegion &dr);

#include "displayRegion.I"

#endif /* DISPLAYREGION_H */