/*
 Copyright (C) 2009 Erik Ogenvik <erik@ogenvik.org>

 This program 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 2 of the License, or
 (at your option) any later version.

 This program 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 this program; if not, write to the Free Software Foundation,
 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#ifndef EMBEROGRETERRAINHEIGHTMAPSEGMENT_H_
#define EMBEROGRETERRAINHEIGHTMAPSEGMENT_H_

#include "IHeightMapSegment.h"

namespace Ember {
namespace OgreView {

namespace Terrain {

class HeightMapBuffer;

/**
 * @author Erik Ogenvik <erik@ogenvik.org>
 * @brief Represents one segment (mapped to a Mercator::Segment) in the height map, backed by a height map buffer.
 */
class HeightMapSegment : public IHeightMapSegment {
public:

	/**
	 * @brief Ctor.
	 * @param buffer The buffer to use for this segment. Ownership will be transferred.
	 */
	explicit HeightMapSegment(std::unique_ptr<HeightMapBuffer> buffer);

	/**
	 * @brief Dtor.
	 */
	~HeightMapSegment() override;

	/**
	 * @brief Gets the height at the specified location.
	 * This is a crude and fast lookup method which won't take into account slopes.
	 * @see getHeightAndNormal()
	 * @param x The x location, in world units.
	 * @param y The y location, in world units.
	 * @returns The height at the location.
	 */
	float getHeight(int x, int y) const override;

	/**
	 * @brief Gets the height and normal at the location.
	 * This calculates slopes and provides a precise height. It's therefore more time consuming than getHeight().
	 * @param x The x location, in world units.
	 * @param y The y location, in world units.
	 * @param height The height will be stored here.
	 * @param normal The normal will be stored here.
	 */
	void getHeightAndNormal(float x, float y, float& height, WFMath::Vector<3>& normal) const override;

private:

	/**
	 * @brief The buffer which contains the height data.
	 */
	std::unique_ptr<HeightMapBuffer> mBuffer;
};

}

}

}

#endif /* EMBEROGRETERRAINHEIGHTMAPSEGMENT_H_ */
