Creating ellipse marker with line pattern fill in QGIS

Question

How can I create an ellipse marker with line pattern fill in QGIS?

Like this:

I have already made simpler symbols, but there is no solution with the ellipse

Answer 1

To get the different symbols for each half of the ellipse:

• make a Geometry Generator symbol layer
• use this expression

with_variable('ellipse',
    make_ellipse( $geometry, 10, 5, 0),    -- make an ellipse and assign it to a variable
        rotate(
            intersection(                  -- get intersection of rectangle and ellipse to 'clip' half of it
                 make_rectangle_3points(   -- make a rectangle that is half the bounding box of the ellipse
                        project($geometry,  y_max(@ellipse) - y($geometry), 0),  -- project a point from the original point directly north by half the height of the ellipse
                        project($geometry,  y_max(@ellipse) - y($geometry), radians(180)),  -- project a point from the original point directly south by half the height of the ellipse
                        make_point(x_max(@ellipse), y_min(@ellipse))  -- make a point of the 'lower right' corner of the bounds of the ellipse
                 ),
                 @ellipse      -- @ellipse is the variable name of the ellipse made above
            ),      
        120, $geometry     -- rotate the half-ellipse, 120 is the rotation angle, $geometry is the center of rotation (the original point geometry)
        )
)

• duplicate the symbol layer
• change angle in rotate by 180 degrees so the new symbol layer aligns with the first (in my case 120->300)
• style the 2 symbol layers as desired
• don't forget to set Units to Millimeter for a scalable symbol

Answer 2

Use Geometry Generator with the following expression:

make_ellipse(centroid($geometry), 1, 2, 0)

Change values 1 (semi_major_axis) and 2 (semi_minor_axis).

Answer 3

You can use a Filled Marker.

• Choose the semi-circle shape
• set your desired rotation and give it a line fill.
• Then add another symbol layer with the semi-circle Filled Marker (or duplicate first symbol layer)
• give it the opposite rotation so they align, make this a simple fill (with No Brush).