orientation_xldorientation_xldOrientationXldOrientationXldorientation_xld (Operator)

Name

orientation_xldorientation_xldOrientationXldOrientationXldorientation_xld — Orientation of contours or polygons.

Signature

Description

The operator orientation_xldorientation_xldOrientationXldOrientationXldOrientationXldorientation_xld calculates the orientation of each input contour or polygon. The operator is based on elliptic_axis_xldelliptic_axis_xldEllipticAxisXldEllipticAxisXldEllipticAxisXldelliptic_axis_xld. In addition, the contour respectively polygon point with maximum distance to the center of gravity is calculated. If the column coordinate of this point is less than the column coordinate of the center of gravity the value of is added to the angle. It is assumed that the contours or polygons are closed. If this is not the case orientation_xldorientation_xldOrientationXldOrientationXldOrientationXldorientation_xld will artificially close the contours or polygons.

It should be noted that orientation_xldorientation_xldOrientationXldOrientationXldOrientationXldorientation_xld only returns useful results if the contour or polygon encloses a region in the plane. In particular, the contour or polygon must not intersect itself. This is particularly important if open contours or polygons are passed because they are closed automatically, which can produce a self-intersection. To test whether the contours or polygons intersect themselves, test_self_intersection_xldtest_self_intersection_xldTestSelfIntersectionXldTestSelfIntersectionXldTestSelfIntersectionXldtest_self_intersection_xld can be used. If the contour or polygon intersects itself, useful values for the orientation can be calculated with orientation_points_xldorientation_points_xldOrientationPointsXldOrientationPointsXldOrientationPointsXldorientation_points_xld.

If more than one contour or polygon is passed, the values of the orientations are stored in a tuple in the same order as the respective contours or polygons in XLDXLDXLDXLDXLDxld.

Execution Information

• Multithreading type: reentrant (runs in parallel with non-exclusive operators).
• Multithreading scope: global (may be called from any thread).
• Automatically parallelized on tuple level.

Parameters

Result

The operator orientation_xldorientation_xldOrientationXldOrientationXldOrientationXldorientation_xld returns the value TRUE if the input is not empty. The behavior in case of empty input (no input contours available) is set via the operator set_system('no_object_result',<Result>)set_system("no_object_result",<Result>)SetSystem("no_object_result",<Result>)SetSystem("no_object_result",<Result>)SetSystem("no_object_result",<Result>)set_system("no_object_result",<Result>). If necessary an exception is raised.

Possible Predecessors

gen_contours_skeleton_xldgen_contours_skeleton_xldGenContoursSkeletonXldGenContoursSkeletonXldGenContoursSkeletonXldgen_contours_skeleton_xld, edges_sub_pixedges_sub_pixEdgesSubPixEdgesSubPixEdgesSubPixedges_sub_pix, threshold_sub_pixthreshold_sub_pixThresholdSubPixThresholdSubPixThresholdSubPixthreshold_sub_pix, gen_contour_polygon_xldgen_contour_polygon_xldGenContourPolygonXldGenContourPolygonXldGenContourPolygonXldgen_contour_polygon_xld, test_self_intersection_xldtest_self_intersection_xldTestSelfIntersectionXldTestSelfIntersectionXldTestSelfIntersectionXldtest_self_intersection_xld

Alternatives

elliptic_axis_xldelliptic_axis_xldEllipticAxisXldEllipticAxisXldEllipticAxisXldelliptic_axis_xld, smallest_rectangle2_xldsmallest_rectangle2_xldSmallestRectangle2XldSmallestRectangle2XldSmallestRectangle2Xldsmallest_rectangle2_xld

See also

moments_region_2ndmoments_region_2ndMomentsRegion2ndMomentsRegion2ndMomentsRegion2ndmoments_region_2nd

Module

Foundation