C++ MyMesh::faces_begin方法代码示例

void KnotsViewer::draw_curvature_error_domain()
{

    if(surfacedata==NULL)
        return;
    if ((surfacedata->get_domain()).empty())
        return;
    MyMesh polymesh = surfacedata->get_polymesh();
    if (polymesh.edges_empty()==true)
        return;
    MyMesh::ConstFaceIter        f_it(polymesh.faces_begin()),f_end(polymesh.faces_end());
    MyMesh::ConstFaceVertexIter  fv_it;
    //glLineWidth(0.5);
    for (; f_it!=f_end; ++f_it)
    {

        glColor3ubv(polymesh.color(*f_it).data());
        glBegin(GL_POLYGON);
        fv_it = polymesh.cfv_iter(*f_it);
        glVertex3dv(&polymesh.point(fv_it)[0]);
        ++fv_it;
        glVertex3dv(&polymesh.point(fv_it)[0]);
        ++fv_it;
        glVertex3dv(&polymesh.point(fv_it)[0]);
        ++fv_it;
        glVertex3dv(&polymesh.point(fv_it)[0]);
        glEnd();
    }


}

void MyGL::setMesh(MyMesh mesh)
{
	
	petal_mesh = mesh;

	points.clear();


	//点
	for (auto it = mesh.vertices_begin(); it != mesh.vertices_end(); ++it){
		auto point = mesh.point(it.handle());
		coor t = { point.data()[0], point.data()[1], point.data()[2] };

		points.push_back(t);

	}

	//面
	face.clear();

	for (auto it = mesh.faces_begin(); it != mesh.faces_end(); ++it){
		OpenMesh::FaceHandle fh = it.handle();

		coor facet;//当前面索引
		int count = 0;//标记第几个点
		for (auto it1 = mesh.fv_begin(fh); it1 != mesh.fv_end(fh); ++it1){
			auto point = mesh.point(it1.handle());
			t = { point.data()[0], point.data()[1], point.data()[2] };

			//find
			vector<coor>::iterator itv;//记录该点对应Points中的位置
			itv = find_if(points.begin(), points.end(), [](coor const& obj){
				return (fabs(obj.x - t.x) < 0.01) && (fabs(obj.y - t.y) < 0.01) && (fabs(obj.z - t.z) < 0.01);
			});

			if (itv != points.end())//写入面facet
			{
				if (count == 0){
					facet.x = itv - points.begin();
				}
				else if (count == 1){
					facet.y = itv - points.begin();
				}
				else
					facet.z = itv - points.begin();
			}
			else
				break;
			count++;


		}
		face.push_back(facet);

	}

	return;
}

/*rasterize the model to 2R*2R*2R voxel grid*/
void RasterizeMesh(MyMesh &mesh,vector<Point> &grid_points)
{
	//reserve space 
	grid_points.reserve(10000);

	//create grid 
	int grid_size = 2*RADIUS*2*RADIUS*2*RADIUS;

	bool *grid;
	grid = new bool [grid_size];
	memset(grid,false,grid_size*sizeof(bool));

	for(MyMesh::FaceIter f_it=mesh.faces_begin();f_it!=mesh.faces_end();++f_it)
	{
		vector<Point> face_points;

		for(MyMesh::FaceVertexIter v_it=mesh.fv_iter(f_it);v_it;++v_it)
		{
			Point temp_face_point;
			//scale back from range [0,1] to [0,2R]
			temp_face_point.x() = *(mesh.point(v_it).data()+0)*2*RADIUS;
			temp_face_point.y() = *(mesh.point(v_it).data()+1)*2*RADIUS;
			temp_face_point.z() = *(mesh.point(v_it).data()+2)*2*RADIUS;
			face_points.push_back(temp_face_point);

			//get grid coordinate
			int grid_coordinate	= int(temp_face_point.x()*2*RADIUS*2*RADIUS + temp_face_point.y()*2*RADIUS + temp_face_point.z());

			//discard points out of range
			if(grid_coordinate>(2*RADIUS*2*RADIUS*2*RADIUS-1) || grid_coordinate<0)  continue; 

			//if not registered
			if(*(grid+grid_coordinate)!=true)
			{
				*(grid+grid_coordinate) = true;
				grid_points.push_back(temp_face_point);
			}
		}

		//fill the edges for a triangle face
		vector<Point> inter12,inter23,inter13;
		int n_points12 = fillGridLine(face_points.at(0),face_points.at(1),inter12,grid,grid_points);
		int n_points23 = fillGridLine(face_points.at(1),face_points.at(2),inter23,grid,grid_points);
		int n_points13 = fillGridLine(face_points.at(0),face_points.at(2),inter13,grid,grid_points);

		//fill in the face
		if(n_points12>=n_points13 && n_points13>0)
		{
			for(unsigned int n=0;n<n_points13;n++)
			{
				vector<Point> temp_inter;
				fillGridLine(inter12.at(n),inter13.at(n),temp_inter,grid,grid_points);
			}
			for(unsigned int n=n_points13;n<n_points12;n++)
			{
				vector<Point> temp_inter;
				fillGridLine(inter12.at(n),inter13.at(inter13.size()-1),temp_inter,grid,grid_points);
			}
		} 
		else if(n_points13>=n_points12 && n_points12>0)
		{
			for(unsigned int n=0;n<n_points12;n++)
			{
				vector<Point> temp_inter;
				fillGridLine(inter12.at(n),inter13.at(n),temp_inter,grid,grid_points);
			}
			for(unsigned int n=n_points12;n<n_points13;n++)
			{
				vector<Point> temp_inter;
				fillGridLine(inter12.at(inter12.size()-1),inter13.at(n),temp_inter,grid,grid_points);
			}
		}
	}

	//get centroid again
	Point centroid_after(0.0,0.0,0.0);
	for(unsigned int p_it = 0;p_it<grid_points.size();p_it++)
	{
		centroid_after.x()+=grid_points.at(p_it).x();
		centroid_after.y()+=grid_points.at(p_it).y();
		centroid_after.z()+=grid_points.at(p_it).z();

	}
	centroid_after.x()/=double(grid_points.size());
	centroid_after.y()/=double(grid_points.size());
	centroid_after.z()/=double(grid_points.size());

	//move grid to the origin
	for(unsigned int p_it = 0;p_it<grid_points.size();p_it++)
	{
		grid_points.at(p_it).x() -= centroid_after.x();
		grid_points.at(p_it).y() -= centroid_after.y();
		grid_points.at(p_it).z() -= centroid_after.z();
	}

	delete [] grid;

	RASTERIZE_CONTROL = FALSE;
}