#include "vtkPVBoxZoom.h"

#include "vtkCamera.h"
#include "vtkObjectFactory.h"
#include "vtkRenderWindowInteractor.h"
#include "vtkCameraManipulatorGUIHelper.h"
#include "vtkRenderer.h"
#include "vtkRenderWindow.h"
#include "vtkMath.h"

vtkCxxRevisionMacro(vtkPVBoxZoom, "$Revision: 1.2 $");
vtkStandardNewMacro(vtkPVBoxZoom);

//-------------------------------------------------------------------------
vtkPVBoxZoom::vtkPVBoxZoom()
{
  this->xPos = 0;
  this->yPos = 0;
}

//-------------------------------------------------------------------------
vtkPVBoxZoom::~vtkPVBoxZoom()
{
}

//-------------------------------------------------------------------------
void vtkPVBoxZoom::OnButtonDown(int x, int y, vtkRenderer *ren,
                                      vtkRenderWindowInteractor *)
{
  xPos = x;
  yPos = y;
}


//-------------------------------------------------------------------------
void vtkPVBoxZoom::OnButtonUp(int x, int y, vtkRenderer *ren,
                                    vtkRenderWindowInteractor *rwi)
{

  if (ren == NULL)
    {
    return;
    }

  // first move into the center of the selected box
  int oldCenter[2];
  int* winsz;
  winsz = ren->GetSize();
  oldCenter[0] = winsz[0] / 2;
  oldCenter[1] = winsz[1] / 2;

  int newCenter[2];
  newCenter[0] = (x + xPos) / 2;
  newCenter[1] = (y + yPos) / 2;

  vtkCamera *camera = ren->GetActiveCamera();
  double pos[3], fp[3];
  camera->GetPosition(pos);
  camera->GetFocalPoint(fp);

  if (camera->GetParallelProjection())
    {
    camera->OrthogonalizeViewUp();
    double *up = camera->GetViewUp();
    double *vpn = camera->GetViewPlaneNormal();
    double right[3];
    double scale, tmp;
    camera->GetViewUp(up);
    camera->GetViewPlaneNormal(vpn);
    vtkMath::Cross(vpn, up, right);

    // These are different because y is flipped.
    int *size = ren->GetSize();
    double dx = (double)(oldCenter[0] - newCenter[0]) / (double)(size[1]);
    double dy = (double)(newCenter[1] - oldCenter[1]) / (double)(size[1]);

    scale = camera->GetParallelScale();
    dx *= scale * 2.0;
    dy *= scale * 2.0;

    tmp = (right[0]*dx + up[0]*dy);
    pos[0] += tmp;
    fp[0] += tmp; 
    tmp = (right[1]*dx + up[1]*dy); 
    pos[1] += tmp;
    fp[1] += tmp; 
    tmp = (right[2]*dx + up[2]*dy); 
    pos[2] += tmp;
    fp[2] += tmp; 
    camera->SetPosition(pos);
    camera->SetFocalPoint(fp);
    }
  else
    {
    double depth, worldPt[4], lastWorldPt[4];
    double center[3];

    this->GetCenter(center[0], center[1], center[2]);
    ren->SetWorldPoint(center[0], center[1], center[2], 1.0);
    
    ren->WorldToDisplay();
    depth = ren->GetDisplayPoint()[2];
    
    ren->SetDisplayPoint(oldCenter[0], oldCenter[1], depth);
    ren->DisplayToWorld();
    ren->GetWorldPoint(worldPt);
    if (worldPt[3])
      {
      worldPt[0] /= worldPt[3];
      worldPt[1] /= worldPt[3];
      worldPt[2] /= worldPt[3];
      worldPt[3] = 1.0;
      }
    
    ren->SetDisplayPoint(newCenter[0],
                         newCenter[1],
                         depth);
    ren->DisplayToWorld();
    ren->GetWorldPoint(lastWorldPt);
    if (lastWorldPt[3])
      {
      lastWorldPt[0] /= lastWorldPt[3];
      lastWorldPt[1] /= lastWorldPt[3];
      lastWorldPt[2] /= lastWorldPt[3];
      lastWorldPt[3] = 1.0;
      }

    pos[0] += lastWorldPt[0] - worldPt[0];
    pos[1] += lastWorldPt[1] - worldPt[1];
    pos[2] += lastWorldPt[2] - worldPt[2];

    fp[0] += lastWorldPt[0] - worldPt[0];
    fp[1] += lastWorldPt[1] - worldPt[1];
    fp[2] += lastWorldPt[2] - worldPt[2];

    camera->SetPosition(pos);
    camera->SetFocalPoint(fp);
    }

  // now do the zoom
  double dx = static_cast<double>(winsz[0]) / static_cast<double>(abs(x - xPos));
  double dy = static_cast<double>(winsz[1]) / static_cast<double>(abs(y - yPos));
  double k = (dx < dy)?dx:dy;
  camera->Zoom(k);

  // update
  ren->ResetCameraClippingRange();
  rwi->Render();	
}

//-------------------------------------------------------------------------
void vtkPVBoxZoom::OnMouseMove(int vtkNotUsed(x), int y,
                                     vtkRenderer *ren,
                                     vtkRenderWindowInteractor *rwi)
{
}

//-------------------------------------------------------------------------
void vtkPVBoxZoom::PrintSelf(ostream& os, vtkIndent indent)
{
  this->Superclass::PrintSelf(os, indent);
}