v.net.allpairs: remove duplicate lines

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@54893 15284696-431f-4ddb-bdfa-cd5b030d7da7

vector/v.net.allpairs/main.c

@@ -25,6 +25,9 @@
 #include <grass/dbmi.h>
 #include <grass/neta.h>
 
+int remove_duplicates(struct Map_info *);
+int check_duplicate(const struct line_pnts *, const struct line_pnts *);
+
 struct _spnode {
     int cat, node;
 };
@@ -279,7 +282,11 @@ int main(int argc, char *argv[])
 		else
 		    Vect_append_points(aPoints, Points,
 				       GV_BACKWARD);
+		aPoints->n_points--;
 	    }
+	    aPoints->n_points++;
+	    
+	    Vect_line_prune(aPoints);
 
 	    Vect_write_line(&Out, GV_LINE, aPoints, Cats);
 
@@ -293,11 +300,144 @@ int main(int argc, char *argv[])
     Vect_copy_head_data(&In, &Out);
     Vect_hist_copy(&In, &Out);
     Vect_hist_command(&Out);
+    Vect_close(&In);
 
+    Vect_build_partial(&Out, GV_BUILD_BASE);
+    Vect_break_lines(&Out, GV_LINE, NULL);
+    remove_duplicates(&Out);
+    Vect_build_partial(&Out, GV_BUILD_NONE);
+    
     Vect_build(&Out);
 
-    Vect_close(&In);
     Vect_close(&Out);
 
     exit(EXIT_SUCCESS);
 }
+
+
+int remove_duplicates(struct Map_info *Map)
+{
+    struct line_pnts *APoints, *BPoints;
+    struct line_cats *ACats, *BCats;
+    int i, c, atype, btype, aline, bline;
+    int nlines, nacats_orig, npoints;
+    struct bound_box ABox;
+    struct boxlist *List;
+    int ndupl, is_dupl;
+
+
+    APoints = Vect_new_line_struct();
+    BPoints = Vect_new_line_struct();
+    ACats = Vect_new_cats_struct();
+    BCats = Vect_new_cats_struct();
+    List = Vect_new_boxlist(0);
+
+    nlines = Vect_get_num_lines(Map);
+
+    G_debug(1, "nlines =  %d", nlines);
+    /* Go through all lines in vector, for each line select lines which
+     * overlap with the first vertex of this line and check if a 
+     * selected line is identical. If yes, remove the selected line.
+     * If the line vertices are identical with those of any other line, 
+     * merge categories and rewrite the current line.
+     */
+
+    ndupl = 0;
+
+    for (aline = 1; aline <= nlines; aline++) {
+	G_percent(aline, nlines, 1);
+	if (!Vect_line_alive(Map, aline))
+	    continue;
+
+	atype = Vect_read_line(Map, APoints, ACats, aline);
+	if (!(atype & GV_LINE))
+	    continue;
+
+	npoints = APoints->n_points;
+	Vect_line_prune(APoints);
+	
+	if (npoints != APoints->n_points) {
+	    Vect_rewrite_line(Map, aline, atype, APoints, ACats);
+	    nlines = Vect_get_num_lines(Map);
+	    continue;
+	}
+
+	/* select potential duplicates */
+	ABox.E = ABox.W = APoints->x[0];
+	ABox.N = ABox.S = APoints->y[0];
+	ABox.T = ABox.B = APoints->z[0];
+	Vect_select_lines_by_box(Map, &ABox, GV_LINE, List);
+	G_debug(3, "  %d lines selected by box", List->n_values);
+	
+	is_dupl = 0;
+
+	for (i = 0; i < List->n_values; i++) {
+	    bline = List->id[i];
+	    G_debug(3, "  j = %d bline = %d", i, bline);
+
+	    /* compare aline and bline only once */
+	    if (aline <= bline)
+		continue;
+
+	    btype = Vect_read_line(Map, BPoints, BCats, bline);
+
+	    if (!(btype & GV_LINE))
+		continue;
+
+	    Vect_line_prune(BPoints);
+
+	    /* check for duplicate */
+	    if (!check_duplicate(APoints, BPoints))
+		continue;
+
+	    /* bline is identical to aline */
+	    is_dupl = 1;
+
+	    Vect_delete_line(Map, bline);
+
+	    /* merge categories */
+	    nacats_orig = ACats->n_cats;
+
+	    for (c = 0; c < BCats->n_cats; c++)
+		Vect_cat_set(ACats, BCats->field[c], BCats->cat[c]);
+
+	    if (ACats->n_cats > nacats_orig) {
+		G_debug(4, "cats merged: n_cats %d -> %d", nacats_orig,
+			ACats->n_cats);
+	    }
+
+	    ndupl++;
+	}
+	if (is_dupl) {
+	    Vect_rewrite_line(Map, aline, atype, APoints, ACats);
+	    nlines = Vect_get_num_lines(Map);
+	    G_debug(3, "nlines =  %d\n", nlines);
+	}
+    }
+    G_verbose_message("Removed duplicates: %d", ndupl);
+    
+    return ndupl;
+}
+
+int check_duplicate(const struct line_pnts *APoints,
+		    const struct line_pnts *BPoints)
+{
+    int k;
+    int npoints;
+
+    if (APoints->n_points != BPoints->n_points)
+	return 0;
+
+    npoints = APoints->n_points;
+
+    /* only forward */
+    for (k = 0; k < npoints; k++) {
+	if (APoints->x[k] != BPoints->x[k] ||
+	    APoints->y[k] != BPoints->y[k] ||
+	    APoints->z[k] != BPoints->z[k]) {
+	    return 0;
+	}
+    }
+
+    return 1;
+}