Subversion Repositories gelsvn

#include <vector>

#include "CGLA/Mat3x3f.h"

#include "CGLA/Vec2f.h"

#include "Face.h"

#include "Manifold.h"

#include "FaceCirculator.h"

using namespace CGLA;

using namespace std;

namespace HMesh

{

	FaceIter get_null_face_iter()

	{

		static FaceList l;

		return l.end();

	}

	template<class R>

	Face_template<R>::Face_template(): 

	last(NULL_HALFEDGE_ITER),

	touched(0)

	{}

	int no_edges(FaceIter f)

	{

		FaceCirculator fc(f);

		while(!fc.end()) ++fc;

		return fc.no_steps();

	}

	Vec3f normal(FaceIter f)

	{

		vector<Vec3f> v;

		FaceCirculator fc(f);

		int k;

		for(k=0;!fc.end();++fc,++k)

		{

			Vec3f p = fc.get_vertex()->pos;

			v.push_back(p);

		}

		Vec3f norm(0);

		for(int i=0;i<k;++i)

		{

			norm[0] += (v[i][1]-v[(i+1)%k][1])*(v[i][2]+v[(i+1)%k][2]);

			norm[1] += (v[i][2]-v[(i+1)%k][2])*(v[i][0]+v[(i+1)%k][0]);

			norm[2] += (v[i][0]-v[(i+1)%k][0])*(v[i][1]+v[(i+1)%k][1]);

		}

		float l = norm.length();

		if(l>0.0f)

			norm /= l;

		return norm;

	}

	float area(FaceIter f)

	{

		FaceCirculator fc(f);

		int k;

		// M is a matrix that projects a vector onto the orthogonal

		// complement of the face normal

		Vec3f n = normal(f);

		Vec3f a,b;

		orthogonal(n, a, b);

		Mat3x3f M(a,b,n);

		// Get all projected vertices

		vector<Vec2f> v;		

		for(k=0;!fc.end();++fc,++k)

		{

			Vec3f p = M * fc.get_vertex()->pos;

			v.push_back(Vec2f(p[0], p[1]));

		}

		float area = 0;

		for(int i=0;i<k;++i)

		{

			area += 0.5 * cross(v[i], v[(i+1)%k]);

		}

		return fabs(area);

	}

	Vec3f centre(FaceIter f)

	{

		Vec3f c(0);

		FaceCirculator fc(f);

		while(!fc.end())

		{

			c += fc.get_vertex()->pos;

			++fc;

		}

		c /= fc.no_steps();

		return c;

	}

	template struct Face_template<Iters>;	

}