Return the names of the defined attributes of an XLD contour.

::query_contour_attribs_xld returns the names of the defined attributes of an XLD contour Contour in Attribs. Attributes are additional values defined for each contour point, e.g. the direction perpendicular to the contour ('angle'). Operators which define this kind of attributes contain a description of the name and semantics of the defined values. ::get_contour_attrib_xld can be used to access the values of a particular attribute.

::lines_gauss, ::lines_facet, ::edges_sub_pix

::get_contour_attrib_xld, ::get_contour_global_attrib_xld, ::query_contour_global_attribs_xld

Sub-pixel operators