Generating parallel points along with lines or outline of polygon

Question

In QGIS using the Geometry generator, how can we generate the square points within a polygon (e.g. built-up layer) that parallel with other features (e.g. road layer) like in the map below?

Answer 1

Given the layer line and polygon, use Geometry generator on the line layer with this expression and style the resulting points with a marker as black squares. What you can adapt:

• Line 10 and 19: the number 10 is the interval (distance) along the street where points should be created.

• Line 15: the number 15 is the lateral distance of the points to both sides from the street.

• 5th last line: replace polygon by the name of your polygon layer.

intersection (
 collect_geometries(
     array_foreach (
         array(90,270),
         with_variable (
             'side',
             @element,
             collect_geometries (
                 array_foreach (
                     generate_series (0, length($geometry), 10),
                     project (
                         line_interpolate_point( 
                             $geometry, @element
                         ),
                         15,
                         radians (
                             @side - line_interpolate_angle( 
                                 $geometry, 
                                 @element/10
                             )
                         )
                     )
                 )
             )
         )
     )
 ),
 aggregate (
     'polygon', 
     'collect', 
     $geometry
 )
)