RRV - Radiosity Renderer and Visualizer (C++, OpenGL)

/*
 * Copyright (C) 2007 TODO
 *
 * This file is part of rrv (Radiosity Renderer and Visualizer).
 *
 * rrv is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * any later version.
 *
 * rrv 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with rrv.  If not, see <http://www.gnu.org/licenses/>.
 */
 
#ifndef PROGRESSSUBJECTMULTISTEP_H
#define PROGRESSSUBJECTMULTISTEP_H
 
/**
 * @file ProgressSubjectMultiStep.h
 * @brief Class ProgressSubjectMultiStep - observer's subject (base for RadiosityRenderer).
 * @author xdudka00
 * @date 2007-11-18
 */
 
#include <list>
 
class ProgressObserverMultiStep;
 
/**
 * @brief Observer's subject. Design pattern @b observer.
 */
class ProgressSubjectMultiStep
{
	public:
		virtual ~ProgressSubjectMultiStep() {}
 
		/**
		 * @brief Attach observer to subject
		 * @param observer Observer to attach.
		 * @param perStepFreq Frequency of callback during step.
		 */
		virtual void attach(ProgressObserverMultiStep *observer, int perStepFreq);
 
		/**
		 * @brief Detach observer from subject.
		 * @param observer Observer to detach.
		 */
		virtual void detach(ProgressObserverMultiStep *observer);
 
		/**
		 * @brief Return total count of steps.
		 */
		virtual int stepCount() const =0;
 
		/**
		 * @brief Return number of current step - always in range <0, stepCount()-1>.
		 */
		virtual int currentStep() const =0;
 
		/**
		 * @brief Return total count of patches.
		 */
		virtual int patchCount() const =0;
 
		/**
		 * @brief Return number of current patch - always in range <0, patchCount()-1>.
		 */
		virtual int currentPatch() const =0;
 
	protected:
		/**
		 * @brief Subject's notification about starting new step.
		 */
		void notifyStep();
 
		/**
		 * @brief Subject's notification about progress.
		 * @note This method should be called with enough frequency to acomplish
		 * observer's request.
		 */
		void notifyPerStepProgress();
 
	private:
		struct TItem {
			int offset;
			int ratio;
			int last;
			ProgressObserverMultiStep *observer;
		};
		typedef std::list<TItem> TList;
		TList observerList_;
		friend class ObserverFinder;
};
 
#endif // PROGRESSSUBJECTMULTISTEP_H