/*
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * 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.
 *
 * ***** END GPL LICENSE BLOCK *****
 */

#ifndef __FREESTYLE_NODE_CAMERA_H__
#define __FREESTYLE_NODE_CAMERA_H__

/** \file blender/freestyle/intern/scene_graph/NodeCamera.h
 *  \ingroup freestyle
 *  \brief Class to represent a light node
 *  \author Stephane Grabli
 *  \date 25/01/2002
 */

#include "Node.h"

#include "../geometry/Geom.h"

#include "../system/FreestyleConfig.h"

namespace Freestyle {

using namespace Geometry;

class NodeOrthographicCamera;

class NodePerspectiveCamera;

class LIB_SCENE_GRAPH_EXPORT NodeCamera : public Node
{
public:
	typedef enum {
		PERSPECTIVE,
		ORTHOGRAPHIC,
		GENERIC,
	} CameraType;

	/*! Default matrices: Identity for both projection and modelview. */
	NodeCamera(CameraType camera_type = GENERIC); 
	NodeCamera(const NodeCamera& iBrother);

	virtual ~NodeCamera() {}

	/*! Accept the corresponding visitor */
	virtual void accept(SceneVisitor& v);

	/*! Matrix is copied */
	void setModelViewMatrix(double modelview_matrix[16]);

	/*! Matrix is copied */
	void setProjectionMatrix(double projection_matrix[16]);

	double * modelViewMatrix()
	{
		return modelview_matrix_;
	}

	double * projectionMatrix()
	{
		return projection_matrix_;
	}

protected:
	// row major right handed matrix
	double modelview_matrix_[16];
	// row major right handed matrix
	double projection_matrix_[16];

	CameraType camera_type_;
};

class LIB_SCENE_GRAPH_EXPORT NodeOrthographicCamera : public NodeCamera
{
public:
	NodeOrthographicCamera();

	/*! Builds a parallel projection matrix a la glOrtho.
	 *    A   0   0   tx
	 *    0   B   0   ty
	 *    0   0   C   tz
	 *    0   0   0   1
	 *
	 *  where
	 *    A =   2              / (right - left)
	 *    B =   2              / (top   - bottom)
	 *    C =  -2              / (far   - near)
	 *    tx = -(right + left) / (right - left)
	 *    ty = -(top + bottom) / (top   - bottom)
	 *    tz = -(zFar + zNear) / (zFar  - zNear)
	 */
	NodeOrthographicCamera(double left, double right, double bottom, double top, double zNear, double zFar);

	double left() const
	{
		return left_;
	}

	double right() const
	{
		return right_;
	}

	double bottom() const
	{
		return bottom_;
	}

	double top() const
	{
		return top_;
	}

	double zNear() const
	{
		return zNear_;
	}

	double zFar() const
	{
		return zFar_;
	}

	NodeOrthographicCamera(const NodeOrthographicCamera& iBrother);

private:
	double left_;
	double right_;
	double bottom_;
	double top_;
	double zNear_;
	double zFar_;
};

class LIB_SCENE_GRAPH_EXPORT NodePerspectiveCamera : public NodeCamera
{
public:
	NodePerspectiveCamera();

	/*! Builds a perspective projection matrix a la gluPerspective.
	 *  Given f defined as follows:
	 *    fovy
	 *    f = cotangent(____)
	 *    2
	 *  The generated matrix is
	 *    (   f                                                         )
	 *    | ______            0             0                0          |
	 *    | aspect                                                      |
	 *    |                                                             |
	 *    |   0               f             0                0          |
	 *    |                                                             |
	 *    |                             zNear+zFar      2*zNear*zFar    |
	 *    |   0               0         __________      ____________    |
	 *    |                             zNear-zFar       zNear-zFar     |
	 *    |                                                             |
	 *    (   0               0             -1               0          )
	 *  \param fovy
	 *    Field of View specified in radians.
	 */
	NodePerspectiveCamera(double fovy, double aspect, double zNear, double zFar);

	/*! Builds a perspective projection matrix a la glFrustum.
	 *    (  2*zNear                                                         )
	 *    | __________           0               A               0           |
	 *    | right-left                                                       |
	 *    |                                                                  |
	 *    |                   2*zNear                                        |
	 *    |     0            __________          B               0           |
	 *    |                  top-bottom                                      |
	 *    |                                                                  |
	 *    |     0                0               C               D           |
	 *    |                                                                  |
	 *    |     0                0               -1              0           |
	 *    (                                                                  )
	 *
	 *        right+left
	 *    A = __________
	 *        right-left
	 *
	 *        top+bottom
	 *    B = __________
	 *        top-bottom
	 *
	 *          zFar+zNear
	 *    C = - __________
	 *          zFar-zNear
	 *
	 *          2*zFar*zNear
	 *    D = - ____________
	 *           zFar-zNear
	 */
	NodePerspectiveCamera(double left, double right, double bottom, double top, double zNear, double zFar);
};

} /* namespace Freestyle */

#endif // __FREESTYLE_NODE_CAMERA_H__
