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

  Program:   Visualization Toolkit
  Module:    $RCSfile: vtkAssembly.h,v $
  Language:  C++
  Date:      $Date: 2001/10/11 13:38:06 $
  Version:   $Revision: 1.46 $


Copyright (c) 1993-2001 Ken Martin, Will Schroeder, Bill Lorensen 
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

 * Redistributions of source code must retain the above copyright notice,
   this list of conditions and the following disclaimer.

 * Redistributions in binary form must reproduce the above copyright notice,
   this list of conditions and the following disclaimer in the documentation
   and/or other materials provided with the distribution.

 * Neither name of Ken Martin, Will Schroeder, or Bill Lorensen nor the names
   of any contributors may be used to endorse or promote products derived
   from this software without specific prior written permission.

 * Modified source versions must be plainly marked as such, and must not be
   misrepresented as being the original software.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS''
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR
ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

=========================================================================*/
// .NAME vtkAssembly - create hierarchies of vtkProp3Ds (transformable props)
// .SECTION Description
// vtkAssembly is an object that groups vtkProp3Ds, its subclasses, and
// other assemblies into a tree-like hierarchy. The vtkProp3Ds and
// assemblies can then be transformed together by transforming just the root
// assembly of the hierarchy.
//
// A vtkAssembly object can be used in place of an vtkProp3D since it is a
// subclass of vtkProp3D. The difference is that vtkAssembly maintains a list
// of vtkProp3D instances (its "parts") that form the assembly. Then, any
// operation that transforms (i.e., scales, rotates, translates) the parent
// assembly will transform all its parts.  Note that this process is
// recursive: you can create groups consisting of assemblies and/or
// vtkProp3Ds to arbitrary depth.
//
// To add an assembly to the renderer's list of props, you only need to
// add the root of the assembly. During rendering, the parts of the
// assembly are rendered during a hierarchical traversal process.

// .SECTION Caveats
// Collections of assemblies are slower to render than an equivalent list
// of actors. This is because to support arbitrary nesting of assemblies, 
// the state of the assemblies (i.e., transformation matrices) must
// be propagated through the assembly hierarchy. 
//
// Assemblies can consist of hierarchies of assemblies, where one actor or
// assembly used in one hierarchy is also used in other hierarchies. However, 
// make that there are no cycles (e.g., parent->child->parent), this will
// cause program failure.
//
// If you wish to create assemblies without any transformation (using the 
// assembly strictly as a grouping mechanism), then you may wish to
// consider using vtkPropAssembly.
 
// .SECTION See Also
// vtkActor vtkTransform vtkMapper vtkPolyDataMapper vtkPropAssembly

#ifndef __vtkAssembly_h
#define __vtkAssembly_h

#include "vtkProp3D.h"
#include "vtkAbstractMapper3D.h"

class vtkAssemblyPaths;
class vtkProp3DCollection;
class vtkMapper;
class vtkProperty;
class vtkActor;

class VTK_RENDERING_EXPORT vtkAssembly : public vtkProp3D
{
public:
  static vtkAssembly *New();

  vtkTypeMacro(vtkAssembly,vtkProp3D);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Add a part to the list of parts.
  void AddPart(vtkProp3D *);

  // Description:
  // Remove a part from the list of parts,
  void RemovePart(vtkProp3D *);

  // Description:
  // Return the parts (direct descendants) of this assembly.
  vtkProp3DCollection *GetParts();

  // Description: 
  // For some exporters and other other operations we must be
  // able to collect all the actors or volumes. These methods
  // are used in that process.
  void GetActors(vtkPropCollection *);
  void GetVolumes(vtkPropCollection *);

  // Description:
  // Render this assembly and all its parts. 
  // The rendering process is recursive.
  // Note that a mapper need not be defined. If not defined, then no geometry 
  // will be drawn for this assembly. This allows you to create "logical"
  // assemblies; that is, assemblies that only serve to group and transform
  // its parts.
  int RenderOpaqueGeometry(vtkViewport *ren);
  int RenderTranslucentGeometry(vtkViewport *ren);

  // Description:
  // Release any graphics resources that are being consumed by this actor.
  // The parameter window could be used to determine which graphic
  // resources to release.
  void ReleaseGraphicsResources(vtkWindow *);

  // Description:
  // Methods to traverse the parts of an assembly. Each part (starting from
  // the root) will appear properly transformed and with the correct
  // properties (depending upon the ApplyProperty and ApplyTransform ivars).
  // Note that the part appears as an instance of vtkProp. These methods
  // should be contrasted to those that traverse the list of parts using
  // GetParts().  GetParts() returns a list of children of this assembly, not
  // necessarily with the correct transformation or properties. To use the
  // methods below - first invoke InitPathTraversal() followed by repeated
  // calls to GetNextPath().  GetNextPath() returns a NULL pointer when the
  // list is exhausted.
  void InitPathTraversal();
  vtkAssemblyPath *GetNextPath();
  int GetNumberOfPaths();

  // Description:
  // Get the bounds for the assembly as (Xmin,Xmax,Ymin,Ymax,Zmin,Zmax).
  void GetBounds(float bounds[6]) {this->vtkProp3D::GetBounds( bounds );};
  float *GetBounds();

  // Description:
  // Override default GetMTime method to also consider all of the
  // assembly's parts.
  unsigned long int GetMTime();

  // Description:
  // Shallow copy of an assembly. Overloads the virtual vtkProp method.
  void ShallowCopy(vtkProp *prop);

//BTX
  // Description:
  // WARNING: INTERNAL METHOD - NOT INTENDED FOR GENERAL USE DO NOT USE THIS
  // METHOD OUTSIDE OF THE RENDERING PROCESS Overload the superclass' vtkProp
  // BuildPaths() method. Paths consist of an ordered sequence of actors,
  // with transformations properly concatenated.
  void BuildPaths(vtkAssemblyPaths *paths, vtkAssemblyPath *path);
//ETX  

protected:
  vtkAssembly();
  ~vtkAssembly();

  // Keep a list of direct descendants of the assembly hierarchy
  vtkProp3DCollection *Parts;

  // Support the BuildPaths() method. Caches last paths built for
  // performance.
  vtkTimeStamp PathTime;
  virtual void UpdatePaths(); //apply transformations and properties recursively
  
private:
  vtkAssembly(const vtkAssembly&);  // Not implemented.
  void operator=(const vtkAssembly&);  // Not implemented.
};

// Description:
// Get the list of parts for this assembly.
inline vtkProp3DCollection *vtkAssembly::GetParts() {return this->Parts;}

#endif




