/* * J3DME Fast 3D software rendering for small devices * Copyright (C) 2001 Onno Hommes * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */package net.jscience.j3dme;/** * Objects of this class represent a virtual world. The virtual world * can hold one or more models. Models are 3D objects that have a defined * geometry and a location in this virtual world. * @see Model */public class World{  public static final int ONE = 256;  private Model[] models;  private int empty = 0;  private int next  = 0;  /**   * Return a virtual world.<p>   * Return a virtual world that can hold the number of specified models   * The number of models cannot be changed during the life of the world.   *   * @param     numberOfModels The maximum number of models this world can host   * @return The virtual world.   */  public World(int numberOfModels){     models = new Model[numberOfModels];  }  /**   * Add a model to the virtual world<p>   * The supplied model will be added to the virtual world and a model   * index will be returned. If you receive a model index of -1 then the   * world cannot host the model because it has reached its maximum capacity.   *   * @param     model The model to add to the world   * @return The world index to the model or -1 if full.   */  public int addModel(Model model){    if (empty==models.length) return -1;    models[empty] = model;    empty++;    return empty-1;  }  /**   * Remove the model from the world<p>   *   * @param     model The model to remove.   */  public void removeModel(Model model){      removeModel(getModelIndex(model));  }  /**   * Remove a model by index<p>   * The supplied index will be used to remove a model from the world.   *   * @param     index The index to the model   */  public void removeModel(int index){      if (index >= 0 && index < empty){         while (index < empty){            models[index]=models[index+1];            index++;         }      empty--;      }  }  /**   * Return the model located at the index<p>   * This method does not check for incorrect indices. Indices   * larger then the worlds capacity minus one or negative indices will   * surely give you some expected array Execptions.   *   * @param     index The index to the model to be retrieved   * @return The model at the supplied index   */  public Model getModel(int index){    return models[index];  }  /**   * Return the current number of models in the world<p>   *   * @return the number of models in the world.   */  public int getNumberOfModels(){    return empty;  }  /**   * Return the model index for the specified model<p>   * Return the index in the world to the supplied model.   */  public int getModelIndex(Model model){     int index = -1;     for (int i=0;i<models.length;i++){       if (models[i] == model) {          index = i;          break;       }     }     return index;  }  public int getMaximumModels(){    return(models.length);  }}