/*

* Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies). 

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description: 

*

*/

#ifndef MATRIX_STACK_H

#define MATRIX_STACK_H

#include "Matrix.h"

namespace shadergen

{

class MatrixStack

{

public:

	static const int MATRIX_STACK_DEPTH = 16;

	/*!

	 * \brief

	 * Default constructor. Initializes sp to 0.

	 */

	MatrixStack (void)

	{

		m_currDepth = 0;

	}

	/*!

	 * \brief

	 * glPushMatrix() implementation.

	 */

	void push (void)

	{

		SG_ASSERT(SG_IN_RANGE<int>(m_currDepth, 0, MATRIX_STACK_DEPTH - 1));

		memcpy(&m_data[m_currDepth + 1], &m_data[m_currDepth], sizeof(Matrix));

		m_currDepth++;

	}

	/*!

	 * \brief

	 * glPopMatrix() implementation

	 */

	void pop (void)

	{

		SG_ASSERT(SG_IN_RANGE<int>(m_currDepth, 1, MATRIX_STACK_DEPTH - 0));

		m_currDepth--;

	}

	/*!

	 * \brief

	 * Get the topmost matrix in the stack.

	 * 

	 * \returns

	 * Returns the topmost matrix in the stack.

	 */

	Matrix& top (void)

	{

		SG_ASSERT(SG_IN_RANGE<int>(m_currDepth, 0, MATRIX_STACK_DEPTH - 1));

		return m_data[m_currDepth];

	}

private:

	int		m_currDepth;

	Matrix	m_data[MATRIX_STACK_DEPTH];

};

} /* namespace shadergen */

#endif /* MATRIX_STACK_H */