alpha bearing_point_point bearing_tpoint_point bearing_tpoint_tpoint closest_point2d_on_segment_ratio closest_point3dz_on_segment_ratio closest_point_on_segment_sphere datum_geog_azimuth datum_geom_azimuth DELTA_UNIX_POSTGRES_EPOCH ensure_valid_geo_geo ensure_valid_tpoint_geo ensure_valid_tpoint_tpoint ensure_valid_trajectory gbox_init_point2d gbox_merge_point2d geo_bearing_fn geog_bearing geog_distance_geos geom_bearing geomeas_to_tpoint geomeas_tpointinst geomeas_tpointinst_iter geomeas_tpointseq_disc geomeas_tpointseq_linear geomeas_tpointseqset geopoint_collinear geopointarr_make_trajectory geopointlinearr_make_trajectory interpolate_point4d_spheroid lw_seg_interact lwcoll_from_points_lines lwline_make lwpoint_cmp lwpoint_sort_cmp lwpointarr_make_trajectory lwpointarr_remove_duplicates lwpointarr_sort MEOS_SEG_INTER_TYPE mrr_distance_geos multipoint_add_inst_free multipoint_make parseg2d_intersection PGIS_FP_TOLERANCE point_get_x point_get_y point_get_z point_grid point_meas_to_lwpoint pointsegm_interpolate pointsegm_locate pointsegm_locate_point seg2d_intersection seg2d_side tgeogpointsegm_intersection tgeompointsegm_intersection tpoint_angular_difference tpoint_as_mvtgeom tpoint_azimuth tpoint_cumulative_length tpoint_decouple tpoint_direction tpoint_geo_bearing_turnpt tpoint_get_coord tpoint_get_x tpoint_get_y tpoint_get_z tpoint_grid tpoint_is_simple tpoint_length tpoint_make_simple tpoint_mvt tpoint_remove_repeated_points tpoint_speed tpoint_tfloat_to_geomeas tpoint_trajectory tpoint_twcentroid tpointinst_decouple tpointinst_grid tpointinst_to_geomeas tpointinst_to_geomeas_iter tpointsegm_bearing_turnpt tpointsegm_intersection_value tpointseq_azimuth tpointseq_azimuth_iter tpointseq_cont_split tpointseq_cont_to_geomeas tpointseq_cont_to_geomeas_segm tpointseq_cumulative_length tpointseq_decouple tpointseq_decouple_iter tpointseq_direction tpointseq_disc_split tpointseq_disc_to_geomeas tpointseq_discstep_find_splits tpointseq_discstep_is_simple tpointseq_grid tpointseq_is_simple tpointseq_length tpointseq_length_2d tpointseq_length_3d tpointseq_linear_find_splits tpointseq_linear_trajectory tpointseq_make_simple tpointseq_remove_repeated_points tpointseq_speed tpointseq_stops_iter tpointseq_twcentroid tpointseq_twcentroid_iter tpointseqset_azimuth tpointseqset_cumulative_length tpointseqset_decouple tpointseqset_direction tpointseqset_grid tpointseqset_is_simple tpointseqset_length tpointseqset_linear_trajectory tpointseqset_make_simple tpointseqset_remove_repeated_points tpointseqset_speed tpointseqset_to_geomeas tpointseqset_to_geomeas_segm tpointseqset_twcentroid

closest_point2d_on_segment_ratio() long double closest_point2d_on_segment_ratio ( const POINT2D *  p, const POINT2D *  A, const POINT2D *  B, POINT2D *  closest  ) Return a long double between 0 and 1 representing the location of the closest point on the 2D segment to the given point, as a fraction of total segment length. Note Function derived from the PostGIS function closest_point_on_segment