Draw a 3D line between two patches in matlab

I have two sets of coordinates in the form of:

    v= (x1 y1 z1 a1 b1 c1,
        x2 y2 z2 a2 b2 c2,
        ....,
        xn yn zn an bn cn)

These are coordinates of vertices from two meshes. I would like to draw a 3D line joining a vertex in mesh1 to corresponding one in mesh2. I am using the `patch` function to display the two meshes. I tried the `plot3` and it seems to connect lines between points in single mesh only.

Code:

    % vertex_coordinates contains vertices of matched keypoints obtained using index. Taking first 50 coordinates from the 2 meshes
    v=[vertex_coordinates1(1:50,:), vertex_coordinates0(1:50,:)];
    x=[v(:,1) v(:,4)];
    y=[v(:,2) v(:,5)];
    z=[v(:,3) v(:,6)];

    figure
    p0 = patch('Faces',faces0,'Vertices',vertex0,'FaceColor','blue','FaceAlpha',.5,'edgecolor', 'none');
    p1 = patch('Faces',faces1,'Vertices',vertex1,'FaceColor','red','FaceAlpha',.2,'edgecolor', 'none');
    axis equal off
    hold on
    plot3(x',y',z')

These coordinates are actually the vertices of the matched keypoints in the two meshes. I used indices of the matches to get the coordinates and draw a line between them. Is there something wrong with my code? Or should I be looking into thresholding my matches?

Answer 1

[Jaswanth]

Hi,

To visualize the connections between corresponding vertices in two meshes using “plot3” function, you need to draw each line individually using a loop. This ensures that each line is plotted, connecting the exact start and end points between the two sets of coordinates.

Refer to the following modified code snipped showing how to loop through each pair of vertices using the “plot3” function:

for i = 1:size(x, 1)
    plot3(x(i, :), y(i, :), z(i, :), 'k-', 'LineWidth', 1.5);
end

Hope it helps.