/*=========================================================================

  Program:   Visualization Toolkit
  Module:    $RCSfile$

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
// .NAME vtkSynchronizedRenderers - synchronizes renderers across processes.
// .SECTION Description
// vtkSynchronizedRenderers is used to synchronize renderers (vtkRenderer and
// subclasses) across processes for parallel rendering. It's designed to be used
// in conjunction with vtkSynchronizedRenderWindows to synchronize the render
// windows among those processes.
// This class handles synchronization of certain render parameters among the
// renderers such as viewport, camera parameters. It doesn't support compositing
// of rendered images across processes on its own. You typically either subclass
// to implement a compositing algorithm or use a renderer capable of compositing
// eg. IceT based renderer.
#ifndef __vtkSynchronizedRenderers_h
#define __vtkSynchronizedRenderers_h

#include "vtkObject.h"
#include "vtkUnsignedCharArray.h" // needed for vtkUnsignedCharArray.
#include "vtkSmartPointer.h" // needed for vtkSmartPointer.

class vtkRenderer;
class vtkMultiProcessController;
class vtkMultiProcessStream;

class VTK_PARALLEL_EXPORT vtkSynchronizedRenderers : public vtkObject
{
public:
  static vtkSynchronizedRenderers* New();
  vtkTypeMacro(vtkSynchronizedRenderers, vtkObject);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Set the renderer to be synchronized by this instance. A
  // vtkSynchronizedRenderers instance can be used to synchronize exactly 1
  // renderer on each processes. You can create multiple instances on
  // vtkSynchronizedRenderers to synchronize multiple renderers.
  virtual void SetRenderer(vtkRenderer*);
  vtkGetObjectMacro(Renderer, vtkRenderer);

  // Description:
  // Set the parallel message communicator. This is used to communicate among
  // processes.
  virtual void SetParallelController(vtkMultiProcessController*);
  vtkGetObjectMacro(ParallelController, vtkMultiProcessController);

  // Description:
  // Enable/Disable parallel rendering. Unless Parallel rendering is on, the
  // cameras won't be synchronized across processes.
  vtkSetMacro(ParallelRendering, bool);
  vtkGetMacro(ParallelRendering, bool);
  vtkBooleanMacro(ParallelRendering, bool);

  // Description:
  // Get/Set the image reduction factor.
  vtkSetClampMacro(ImageReductionFactor, int, 1, 50);
  vtkGetMacro(ImageReductionFactor, int);

  // Description:
  // If on (default), the rendered images are pasted back on to the screen. You
  // should turn this flag off on processes that are not meant to be visible to
  // the user.
  vtkSetMacro(WriteBackImages, bool);
  vtkGetMacro(WriteBackImages, bool);
  vtkBooleanMacro(WriteBackImages, bool);

  // Description:
  // Get/Set the root-process id. This is required when the ParallelController
  // is a vtkSocketController. Set to 0 by default (which will not work when
  // using a vtkSocketController but will work for vtkMPIController).
  vtkSetMacro(RootProcessId, int);
  vtkGetMacro(RootProcessId, int);

  // Description:
  // Computes visible prob bounds. This must be called on all processes at the
  // same time. The collective result is made available on all processes once
  // this method returns.
  // Note that this method requires that bounds is initialized to some value.
  // This expands the bounds to include the prop bounds.
  void CollectiveExpandForVisiblePropBounds(double bounds[6]);

  // Description:
  // When set, this->CaptureRenderedImage() does not capture image from the
  // screen instead passes the call to the delegate.
  virtual void SetCaptureDelegate(vtkSynchronizedRenderers*);
  vtkGetObjectMacro(CaptureDelegate, vtkSynchronizedRenderers);

//BTX
  enum 
    {
    SYNC_RENDERER_TAG = 15101,
    RESET_CAMERA_TAG  = 15102,
    COMPUTE_BOUNDS_TAG = 15103
    };

  /// vtkRawImage can be used to make it easier to deal with images for
  /// compositing/communicating over client-server etc.
  struct VTK_PARALLEL_EXPORT vtkRawImage
    {
  public:
    vtkRawImage()
      {
      this->Valid = false;
      this->Size[0] = this->Size[1] = 0;
      this->Data = vtkSmartPointer<vtkUnsignedCharArray>::New();
      }

    void Resize(int dx, int dy, int numcomps)
      {
      this->Valid = false;
      this->Allocate(dx, dy, numcomps);
      }

    void MarkValid() { this->Valid = true; }
    void MarkInValid() { this->Valid = false; }

    bool IsValid() { return this->Valid; }
    int GetWidth() { return this->Size[0];} 
    int GetHeight() { return this->Size[1];} 
    vtkUnsignedCharArray* GetRawPtr()
      { return this->Data; }

    // Pushes the image to the viewport.
    bool PushToViewport(vtkRenderer*);

    // Captures the image from the viewport.
    // This doesn't trigger a render, just captures what's currently there in
    // the active buffer.
    bool Capture(vtkRenderer*);

  private:
    bool Valid;
    int Size[2];
    vtkSmartPointer<vtkUnsignedCharArray> Data;

    void Allocate(int dx, int dy, int numcomps);
    };
//ETX
protected:
  vtkSynchronizedRenderers();
  ~vtkSynchronizedRenderers();

  struct RendererInfo
    {
    int ImageReductionFactor;
    int Draw;
    int CameraParallelProjection;
    double Viewport[4];
    double CameraPosition[3];
    double CameraFocalPoint[3];
    double CameraViewUp[3];
    double CameraWindowCenter[2];
    double CameraClippingRange[2];
    double CameraViewAngle;
    double CameraParallelScale;

    // Save/restore the struct to/from a stream.
    void Save(vtkMultiProcessStream& stream);
    bool Restore(vtkMultiProcessStream& stream);

    void CopyFrom(vtkRenderer*);
    void CopyTo(vtkRenderer*);
    };

  // These methods are called on all processes as a consequence of corresponding
  // events being called on the renderer.
  virtual void HandleStartRender();
  virtual void HandleEndRender();
  virtual void HandleAbortRender() {}

  virtual void MasterStartRender();
  virtual void SlaveStartRender();

  virtual void MasterEndRender();
  virtual void SlaveEndRender();

  vtkMultiProcessController* ParallelController;
  vtkRenderer* Renderer;

  // Description:
  // Can be used in HandleEndRender(), MasterEndRender() or SlaveEndRender()
  // calls to capture the rendered image. If this->ImageReductionFactor, then
  // the image will be capture in this->ReducedImage, otherwise it will be
  // captured in this->FullImage (this->ReducedImage will be pointing to the
  // same image).
  virtual vtkRawImage& CaptureRenderedImage();

  // Description:
  // Can be used in HandleEndRender(), MasterEndRender() or SlaveEndRender()
  // calls to paste back the image from either this->ReducedImage or
  // this->FullImage info the viewport.
  void PushImageToScreen(); 

  vtkSynchronizedRenderers* CaptureDelegate;
  vtkRawImage ReducedImage;
  vtkRawImage FullImage;

  bool ParallelRendering;
  int ImageReductionFactor;
  bool WriteBackImages;
  int RootProcessId;

private:
  vtkSynchronizedRenderers(const vtkSynchronizedRenderers&); // Not implemented
  void operator=(const vtkSynchronizedRenderers&); // Not implemented

  class vtkObserver;
  vtkObserver* Observer;
  friend class vtkObserver;

  double LastViewport[4];
};

#endif

