/*
 * 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.
 */

/** \file blender/freestyle/intern/scene_graph/NodeTransform.cpp
 *  \ingroup freestyle
 *  \brief Class to represent a transform node. A Transform node contains one or several children,
 *  \brief all affected by the transformation.
 */

#include "NodeTransform.h"

#include "BLI_math.h"

namespace Freestyle {

void NodeTransform::Translate(real x, real y, real z)
{
	_Matrix(0, 3) += x;
	_Matrix(1, 3) += y;
	_Matrix(2, 3) += z;
}

void NodeTransform::Rotate(real iAngle, real x, real y, real z)
{
	//Normalize the x,y,z vector;
	real norm = (real)sqrt(x * x + y * y + z * z);
	if (0 == norm)
		return;

	x /= norm;
	y /= norm;
	z /= norm;

	/* find the corresponding matrix with the Rodrigues formula:
	 * R = I + sin(iAngle)*Ntilda + (1-cos(iAngle))*Ntilda*Ntilda
	 */
	Matrix33r Ntilda;
	Ntilda(0, 0) = Ntilda(1, 1) = Ntilda(2, 2) = 0.0f;
	Ntilda(0, 1) = -z;
	Ntilda(0, 2) = y;
	Ntilda(1, 0) = z;
	Ntilda(1, 2) = -x;
	Ntilda(2, 0) = -y;
	Ntilda(2, 1) = x;

	const Matrix33r Ntilda2(Ntilda * Ntilda);


	const real sinAngle = (real)sin((iAngle / 180.0f) * M_PI);
	const real cosAngle = (real)cos((iAngle / 180.0f) * M_PI);

	Matrix33r NS(Ntilda * sinAngle);
	Matrix33r NC(Ntilda2 * (1.0f - cosAngle));
	Matrix33r R;
	R = Matrix33r::identity();
	R += NS + NC;

	// R4 is the corresponding 4x4 matrix
	Matrix44r R4;
	R4 = Matrix44r::identity();

	for (int i = 0; i < 3; i++) {
		for (int j = 0; j < 3; j++)
			R4(i, j) = R(i, j);
	}

	// Finally, we multiply our current matrix by R4:
	Matrix44r mat_tmp(_Matrix);
	_Matrix = mat_tmp * R4;
}

void NodeTransform::Scale(real x, real y, real z)
{
	_Matrix(0, 0) *= x;
	_Matrix(1, 1) *= y;
	_Matrix(2, 2) *= z;

	_Scaled = true;
}

void NodeTransform::MultiplyMatrix(const Matrix44r &iMatrix)
{
	Matrix44r mat_tmp(_Matrix);
	_Matrix = mat_tmp * iMatrix;
}

void NodeTransform::setMatrix(const Matrix44r &iMatrix)
{
	_Matrix = iMatrix;
	if (isScaled(iMatrix))
		_Scaled = true;
}

void NodeTransform::accept(SceneVisitor& v)
{
	v.visitNodeTransform(*this);

	v.visitNodeTransformBefore(*this);
	for (vector<Node *>::iterator node = _Children.begin(), end = _Children.end(); node != end; ++node)
		(*node)->accept(v);
	v.visitNodeTransformAfter(*this);
}

void NodeTransform::AddBBox(const BBox<Vec3r>& iBBox)
{
	Vec3r oldMin(iBBox.getMin());
	Vec3r oldMax(iBBox.getMax());

	// compute the 8 corners of the bbox
	HVec3r box[8];
	box[0] = HVec3r(iBBox.getMin());
	box[1] = HVec3r(oldMax[0], oldMin[1], oldMin[2]);
	box[2] = HVec3r(oldMax[0], oldMax[1], oldMin[2]);
	box[3] = HVec3r(oldMin[0], oldMax[1], oldMin[2]);
	box[4] = HVec3r(oldMin[0], oldMin[1], oldMax[2]);
	box[5] = HVec3r(oldMax[0], oldMin[1], oldMax[2]);
	box[6] = HVec3r(oldMax[0], oldMax[1], oldMax[2]);
	box[7] = HVec3r(oldMin[0], oldMax[1], oldMax[2]);

	// Computes the transform iBBox
	HVec3r tbox[8];
	unsigned int i;
	for (i = 0; i < 8; i++)
		tbox[i] = _Matrix * box[i];

	Vec3r newMin(tbox[0]);
	Vec3r newMax(tbox[0]);
	for (i = 0; i < 8; i++) {
		for (unsigned int j = 0; j < 3; j++) {
			if (newMin[j] > tbox[i][j])
				newMin[j] = tbox[i][j];
			if (newMax[j] < tbox[i][j])
				newMax[j] = tbox[i][j];
		}
	}

	BBox<Vec3r> transformBox(newMin, newMax);

	Node::AddBBox(transformBox);
}

bool NodeTransform::isScaled(const Matrix44r &M)
{
	for (unsigned int j = 0; j < 3; j++) {
		real norm = 0;
		for (unsigned int i = 0; i < 3; i++) {
			norm += M(i, j) * M(i, j);
		}
		if ((norm > 1.01) || (norm < 0.99))
			return true;
	}

	return false;
}

} /* namespace Freestyle */