polysweepoptsbous

Options for polygon sweep path with boustrophedon pattern

Since R2026a

Description

The polysweepoptsbous object stores options for sweeping a polygon with a boustrophedon pattern using the polygonSweep function.

This figure shows an example of a polygon swept with a boustrophedon pattern with a sweep angle of 0 and the boundary behavior set to “inset”. Note that the sweep angle refers to the angle of the sweep direction, not the lines of the sweep path.

Creation

Syntax

polysweepoptsbous

polysweepoptsbous(PropertyName=Value)

Description

polysweepoptsbous creates a polygon sweep options object with default properties.

polysweepoptsbous(PropertyName=Value) sets one or more properties using name-value arguments.

Properties

SweepToolGeometry — Geometry of tool used to sweep coverage path

nsidedpoly(4,SideLength=1) (default) | polyshape object

Geometry of the tool used to sweep the coverage path, specified as a polyshape object. The (0, 0) point of the polyshape aligns with the sweep path.

Example: polyshape([-1 1 4 -4],[2 2 -2 -2])

OrientationBehavior — Orientation of sweep tool relative to sweep path

"fixed" (default) | "oriented"

Orientation of the sweep tool relative to the sweep path, specified as "fixed" or "oriented".

• "fixed" — Fix the tool orientation to the initial positive sweep-line direction.

• "oriented" — Realign the tool to the direction of each sweep line.

SweepAngle — Desired sweep angle

0 (default) | numeric scalar in range [0, 2π) | NaN

Desired sweep angle, specified as either a numeric scalar in the range [0, 2π) or NaN. If you specify NaN, the polygonSweep function attempts to determine the optimal sweep angle for the specified polygon.

The sweep angle determines the sweep direction.

SweepLineDirections — Initial and final path directions normal to desired sweep angle

[1 1] (default) | two-element vector of integers in range [–1, 1]

Initial and final path directions normal to the desired sweep angle, specified as a two-element vector of integers in the range [–1, 1]. The first element specifies the initial path direction, and the second element specifies the final path direction.

• 1 — Path direction is normal to the desired sweep angle.

• -1 — Path direction is negative normal to the desired sweep angle.

• 0 — The polygonSweep function follows the path direction that results in the fewest number of passes in the sweep path.

This image shows the relationship between the sweep direction and the sweep line directions.

For example, the first figure in this image shows a SweepLineDirections value of [1 -1], which causes the sweep path to start with a positive direction and end with a negative direction relative to the sweep direction. In the second figure, the start and end directions are both positive with respect to the sweep direction.

In cases where you have sweep paths for separate polygon regions, you can use the SweepLineDirections name-value argument to match the direction at the end of the first sweep path with the start of another sweep path to create smooth transitions between the sweep paths.

MinSidelap — Minimum overlap distance between adjacent sweep lines

0 (default) | numeric scalar

Minimum overlap distance between adjacent sweep lines, specified as a numeric scalar, in meters.

This figure shows the minimum overlap.

BoundaryBehavior — Boundary constraint on the path based on geometry of sweep tool

"tight" (default) | "inset"

Boundary constraint on the path based on the geometry of the sweep tool, specified as "inset" or "tight".

• "tight" — The sweep tool can exit the boundaries of the swept polyshape as necessary to ensure that the sweep tool can completely cover the polygon.

• "inset" — The sweep tool must remain inside swept polyshape. Depending on the geometry of the sweep tool and the polyshape being swept, the sweep tool might not completely cover the polygon.

Examples

Analyze Polygon Monotonicity to Identify Valid Sweep Directions

Define the geometry of a polygon as a polyshape object.

poly = polyshape([0 0 1.5 3 3 1.875 1.5 1.1250 0],[0 2 1.5 2 0 0 0.5 0 0]);

Check if any regions of the polygon are monotonic, and return the monotonic angle intervals for those regions.

[isMono,intervals] = polygonMonotonicity(poly);

Plot the monotonic intervals of the polygon.

hVis = plotMonotonicity(poly);
axis equal tight
title(["Polygon and Corresponding","Monotonic Intervals"])
legend("Polygon","Monotonic Intervals",Location="northeastoutside")

You can use these monotonic intervals to plan sweep paths. Sweeping in a monotonic interval ensures that you can fully sweep the corresponding region of a polygon in one direction, without needing to backtrack.

Store three sweep angles from within the first monotonic angle interval.

sweepAngles = [intervals(1,1) mean(intervals(1,:)) intervals(1,2)] - pi;

Define the geometry of the sweep tool. In this case, assume the tool is shaped like a regular pentagon.

tool = nsidedpoly(5,Radius=0.1);

Set up three subplots, for showing the sweep paths along the selected sweep angles.

t = tiledlayout(1,3,Padding="compact",TileSpacing="compact");

Generate and plot a sweep path for each of the stored sweep angles. Plot the sweep direction arrow and sweep line direction arrow to show their relationships to the sweep angle and path.

for i = 1:3
opts = polysweepoptsbous(SweepAngle=sweepAngles(i),BoundaryBehavior="inset",SweepToolGeometry=tool);
path = polygonSweep(poly,opts);

nexttile

hVis = plotMonotonicity(poly);

hold on
axis equal tight

% Plot the swept path
pathHandle = plot(path(:,1),path(:,2));

% Plot the sweep direction arrow and sweep line direction arrows to
% show their relationships to the sweep angle and path.
sweepLineDirHandle = exampleHelperHighlightInterval(hVis,sweepAngles(i)+pi/2);
sweepDirHandle = exampleHelperPlotSweepDirection(poly,sweepAngles(i));

% Add a title to the current tile
title("Sweep Angle " + num2str(rad2deg(sweepAngles(i)),"%.1f") + "°");

hold off
end

handles = [hVis.MonotoneIntervals.Children(1), ...
           pathHandle, ...
           sweepDirHandle, ...
           sweepLineDirHandle];

legend(handles,{"Monotonic Interval","Sweep Path","Sweep Direction","Sweep Line Direction"},Location="southoutside",Orientation="vertical");

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

Version History

Introduced in R2026a