teengine.cpp

海量地形数据漫游系统,对于OPENGL开发人员具有一定的参考

//##################################################
//# $Id: TeEngine.cpp 28 2005-08-28 10:37:47Z peciva $

/*****************************************************************************\
 *
 * TeEngine.cpp
 *
 * TeEngine - terrain engine class
 *
 * Authors: Martin Havl龛ek (xhavli15 AT stud.fit.vutbr.cz)
 *          PCJohn (peciva AT fit.vutbr.cz)
 * Contributors: 
 *
 * ----------------------------------------------------------------------------
 *
 * THIS SOFTWARE IS NOT COPYRIGHTED
 *
 * This source code is offered for use in the public domain.
 * You may use, modify or distribute it freely.
 *
 * This source code is distributed in the hope that it will be useful but
 * WITHOUT ANY WARRANTY.  ALL WARRANTIES, EXPRESS OR IMPLIED ARE HEREBY
 * DISCLAIMED.  This includes but is not limited to warranties of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * If you find the source code useful, authors will kindly welcome
 * if you give them credit and keep their names with their source code.
 *
\*****************************************************************************/


#include <Inventor/nodes/SoSeparator.h>
#include <Inventor/errors/SoDebugError.h>

#include <cstdlib>    // NULL
#include <ctime>      // time

#include "TeEngine.h"


//----------------------------------------------------------------------------
/**
 * Default constructor.
 *
 * Does some default choices, that can be modified later.
 * TeEngine::FAULT_FORMATION is selected as a generator and TeEngine::LINEAR
 * as a filter.
 *
 * \param hmapResolution Resolution of the patches' heightmaps. If left blank,
 *        default value is used.
 * \param patch0Size Area occupied by the patch in the world-space. If left
 *        blank, default value is used.
 */
TeEngine::TeEngine(SbVec2s hmapResolution, SbVec2f patch0Size) : root(NULL),
  currGen(FAULT_FORMATION), currFilter(LINEAR), HUDCamera(NULL), HUDRoot(NULL),
  sceneCamera(NULL), sceneRoot(NULL), activeObject(NULL), fps(0.0f),
  tasksInQueue(0), patchesNum(0)
{
  this->hmapResolution = hmapResolution;
  this->patch0Size = patch0Size;
  generator = &faultFormation;
}


//----------------------------------------------------------------------------
/**
 * Destructor.
 */
TeEngine::~TeEngine()
{
  delete root;
}


//-----------------------------------------------------------------------------
/**
 * Private attribute accessor.
 *
 * \return Patch height map resolution.
 *
 * \sa hmapResolution
 */
const SbVec2s& TeEngine::getHMapResolution() const
{
  return hmapResolution;
}


//-----------------------------------------------------------------------------
/**
 * Computes patch build maps resolution.
 *
 * Build maps have to have double sized dimensions than the resulting height
 * map (minus 1).
 *
 * \return Patch build map resolution.
 */
SbVec2s TeEngine::getBuildMapResolution() const
{
  return hmapResolution * 2 - SbVec2s(1,1);
}


//-----------------------------------------------------------------------------
/**
 * Private attribute accessor.
 *
 * \return Patch height map resolution.
 *
 * \sa patch0Size
 */
const SbVec2f& TeEngine::getPatch0Size() const
{
  return patch0Size;
}


//-----------------------------------------------------------------------------
/**
 * Private attribute accessor.
 *
 * \return Currently selected generation method.
 *
 * \sa currGen, setCurrGen()
 */
TeEngine::GenMethod TeEngine::getCurrGen()
{
  return currGen;
}


//-----------------------------------------------------------------------------
/**
 * Sets currently selected generation method to \a m
 *
 * This method will be used when new task is scheduled or when generateHMap()
 * method is called.
 *
 * \param m Selected generation method.
 *
 * \sa currGen, getCurrGen(), schedule()
 */
void TeEngine::setCurrGen(GenMethod m)
{
  currGen = m;
}


//-----------------------------------------------------------------------------
/**
 * Private attribute accessor.
 *
 * \return Currently selected filtration method.
 *
 * \sa currFilter, setCurrFilter()
 */
TeEngine::FilterMethod TeEngine::getCurrFilter()
{
  return currFilter;
}


//-----------------------------------------------------------------------------
/**
 * Sets currently selected filtration method to \a m
 *
 * This method will be used when new task is scheduled or when generateHMap()
 * method is called.
 *
 * \param m Selected filtration method.
 *
 * \sa currFilter, getCurrFilter(), schedule()
 */
void TeEngine::setCurrFilter(FilterMethod m)
{
  currFilter = m;
}


//-----------------------------------------------------------------------------
/**
 * Adds object into the engine.
 *
 * \param obj Object to be added to the object list.
 *
 * \sa objectList, getObject(), removeObject()
 */
void TeEngine::addObject(TeObject *obj)
{
  obj->engine = this;
  objectList.append(obj);
  sceneRoot->addChild(obj->getSceneGraph());
}


//-----------------------------------------------------------------------------
/**
 * Gets object from the object list.
 *
 * \param idx Index into the object list.
 * \return Object at index \a idx in the object list
 *
 * \sa objectList, addObject(), removeObject()
 */
TeObject *TeEngine::getObject(int idx)
{
  return objectList[idx];
}


//-----------------------------------------------------------------------------
/**
 * Removes the \a object from engine.
 *
 * \param obj Object to be removed from the object list.
 *
 * \sa objectList, addObject(), getObject()
 */
void TeEngine::removeObject(TeObject *obj)
{
  objectList.removeItem(obj);
}


//-----------------------------------------------------------------------------
/**
 * Sets active object.
 *
 * \param obj Object to be set as active.
 *
 * \sa activeObject, getActiveObject()
 */
void TeEngine::setActiveObject(TeObject *obj)
{
  activeObject = obj;
}


//-----------------------------------------------------------------------------
/**
 * Gets active object.
 *
 * \return Currently active object.
 *
 * \sa activeObject, setActiveObject()
 */
TeObject *TeEngine::getActiveObject()
{
  return activeObject;
}


//-----------------------------------------------------------------------------
/**
 * Sets whole scene root.
 *
 * All objects managed by the engine will be added to the scene as children
 * of this node.
 *
 * \param sep Selected scene root.
 *
 * \sa sceneRoot, getSceneRoot()
 */
void TeEngine::setSceneRoot(SoSeparator *sep)
{
  sceneRoot = sep;
}


//-----------------------------------------------------------------------------
/**
 * Private attribute accessor.
 *
 * \return Whole scene root.
 *
 * \sa sceneRoot, setSceneRoot()
 */
SoSeparator* TeEngine::getSceneRoot()
{
  return sceneRoot;
}


//-----------------------------------------------------------------------------
/**
 * Adds \a node to scene.
 *
 * This function checks, whether the \a node is already present. If it is,
 * nothing happens. This prevents from adding the same \a node into the
 * scene several times. Helpful when adding seams into the scene graph.
 *
 * Note, that modifications to the scene graph are not allowed during the
 * rendering traversal of the tree. Violation of this condition results
 * usually in application crash.
 *
 * \param node Node to be added to the scene.
 *
 * \sa sceneRoot, removeNode()
 */
void TeEngine::addNode(SoNode *node)
{
  if (sceneRoot->findChild(node) == -1) sceneRoot->addChild(node);
}


//-----------------------------------------------------------------------------
/**
 * Removes \a node from scene.
 *
 * This function checks, whether the \a node is truly present. If it isn't,
 * nothing happens.
 *
 * Note, that modifications to the scene graph are not allowed during the
 * rendering traversal of the tree. Violation of this condition results
 * usually in application crash.
 *
 * \param node Node to be removed from the scene.
 *