%--------------------------
 % @Author: Jingqiao Hu
 % @Date: 2021-06-16 15:55:30
 % @LastEditTime: 2021-08-05 21:15:22

 % plot on one coarse-ele, over different nodes
%--------------------------
function plot_NH(cx, cy, lx, microx, nelx, nely, addNum, NH)
    
    dx = lx / microx;
    [gridx, gridy] = meshgrid(0:2*dx:2*lx, 0:2*dx:2*lx);
    gridy = flipud(gridy);

    for e = 1:1
        NHe = NH{e,1}; % [(microx+1)^2, 2, 2, nnodes]
    
        for node = 1:4
%         for i = 1:2
%         for j = 1:2
            figure;
            NHi = NHe(:,:,:,node);

            cv = reshape(NHi(:,2,2), microx+1, microx+1);
            s = surf(gridx, gridy, cv); 
            colormap(jet); caxis([0,1]);
            s.FaceColor = 'w';
            s.EdgeColor = [0.2,0.2,0.2];
            
            hold on;
            grid off; axis equal; axis off;
            set(gca,'FontSize',14,'FontWeight','bold');
%         end
%         end
        end
    end            
end

% if vx / vy < 0, means taking all indices
function nodes2 = project_force(vx, vz, nodes)
    nodes(:,3) = 1:size(nodes,1);
    if vx > -1e-3 % valid
        v = min(abs(nodes(:,1) - vx));
        [ix, ~] = find(abs(nodes(:,1)-v-vx) < 1e-3);
        nodes1 = nodes(ix, :);
    else
        nodes1 = nodes;
    end

    if vz > -1e-3 % valid
        v = min(abs(nodes1(:,2) - vz));
        [iz, ~] = find(abs(nodes1(:,2)-v-vz) < 1e-3);
        nodes2 = nodes1(iz, 3);
    else
        nodes2 = nodes1(:,3);
    end
end