Why do line and patch objects overlap or intersect incorrectly in MATLAB figures?

Why do line and patch objects overlap or intersect incorrectly in MATLAB figures?

I created a three-dimensional plot that contains patch and line objects, using the folowing code:

ax = newplot;
vert = [ -.5, -.5,  0;
                .5, -.5,  0;
                .5,  .5,  0;
               -.5,  .5,  0;
                 0,   0, -1;
                 0,   0,  1];
             
face = [1 2 5;
        2 3 5;
        3 4 5;
        4 1 5;
        1 6 2;
        2 6 3;
        3 6 4;
        4 6 1];
    
patch('Faces',face,...
          'Vertices',vert,...
          'FaceColor','red',...
          'EdgeColor','black');
view(ax,3)     

hold on

plot3([0 0],[-.5 .5],[-1 1])

The line should intersect the faces of the patch. However, the line appears to intersect the edge of the patch. Rotating the axes may cause the line to disappear from sight, or appear completely inside the patch.

Answer 1

[MathWorks Support Team]

This effect is the result of using the painters renderer, which does not display overlapping or intersection correctly. Changing the figure's Renderer property to specify the OpenGL or zbuffer renderer will display the objects properly:

set(gcf,'Renderer','opengl')

or

set(gcf,'Renderer','zbuffer')

for more information on specifying the renderer in MATLAB, see the doc page on "Figure Properties"

https://www.mathworks.com/help/matlab/ref/matlab.ui.figure.html#property_d119e283912