Index: osm.c
===================================================================
--- osm.c	(revision 4854)
+++ osm.c	(working copy)
@@ -710,6 +710,7 @@
 	"w	waterway=canal		water_canal\n"
 	"w	waterway=drain		water_drain\n"
 	"w	waterway=river		water_river\n"
+	"w	water=river		water_river\n"
 	"w	waterway=riverbank	poly_water\n"
 	"w	waterway=stream		water_stream\n"
 	"w	barrier=ditch	ditch\n"
@@ -1544,6 +1545,19 @@
 		if (!strcmp(v,"administrative") || (experimental && !strcmp(v,"postal_code"))) {
 			boundary=1;
 		}
+	} else if (!strcmp(k,"natural")) {
+		if (!strcmp(v,"water") ) {
+			boundary=1;
+		}
+	} else if (!strcmp(k,"waterway")) {
+		if (!strcmp(v,"riverbank") ) {
+printf("FOUND waterway=riverbank\n");
+			boundary=1;
+		}
+	} else if (!strcmp(k,"water")) {
+		if (!strcmp(v,"river") ) {
+			boundary=1;
+		}
 	} else if (!strcmp(k,"ISO3166-1")) {
 		strcpy(iso_code, v);
 	}
@@ -2578,7 +2592,8 @@
 				if (ni) {
 					c[i]=ni->c;
 					if (ni->ref_way > 1 && i != 0 && i != ccount-1 && i != last && item_get_default_flags(ib->type)) {
-						write_item_part(out, out_index, out_graph, ib, last, i, &last_id);
+						if(!(0 != self_intersect_test(ib) && ib->type==type_poly_water))
+							write_item_part(out, out_index, out_graph, ib, last, i, &last_id);
 						last=i;
 					}
 				} else if (final) {
@@ -2594,9 +2609,12 @@
 			}
 		}
 		if (ccount) {
-			write_item_part(out, out_index, out_graph, ib, last, ccount-1, &last_id);
+			//if(0 == self_intersect_test(ib))
+			if(!(0 != self_intersect_test(ib) && ib->type==type_poly_water))
+				write_item_part(out, out_index, out_graph, ib, last, ccount-1, &last_id);
 			if (final && ib->type == type_water_line && out_coastline) {
-				write_item_part(out_coastline, NULL, NULL, ib, last, ccount-1, NULL);
+				if(0 == self_intersect_test(ib))
+					write_item_part(out_coastline, NULL, NULL, ib, last, ccount-1, NULL);
 			}
 		}
 	}
Index: maptool.c
===================================================================
--- maptool.c	(revision 4854)
+++ maptool.c	(working copy)
@@ -854,9 +854,6 @@
 		}
 	}
 
-	if (start_phase(&p,"generating coastlines")) {
-		osm_process_coastlines(&p, suffix);
-	}
 	if (start_phase(&p,"assinging towns to countries")) {
 		FILE *towns=tempfile(suffix,"towns",0),*boundaries=NULL,*ways=NULL;
 		if (towns) {
@@ -870,6 +867,10 @@
 				tempfile_unlink(suffix,"towns");
 		}
 	}
+
+	if (start_phase(&p,"generating coastlines")) {
+		osm_process_coastlines(&p, suffix);
+	}
 	if (start_phase(&p,"sorting countries")) {
 		sort_countries(p.keep_tmpfiles);
 		p.countries_loaded=1;
Index: maptool.h
===================================================================
--- maptool.h	(revision 4854)
+++ maptool.h	(working copy)
@@ -121,6 +121,7 @@
 struct boundary {
 	struct item_bin *ib;
 	struct country_table *country;
+	char *natural;
 	char *iso2;
 	GList *segments,*sorted_segments;
 	GList *children;
@@ -189,6 +190,7 @@
 int geom_poly_segments_point_inside(GList *in, struct coord *c);
 void clip_line(struct item_bin *ib, struct rect *r, struct tile_parameter *param, struct item_bin_sink *out);
 void clip_polygon(struct item_bin *ib, struct rect *r, struct tile_parameter *param, struct item_bin_sink *out);
+int self_intersect_test(struct item_bin*ib);
 
 /* itembin.c */
 
@@ -240,6 +242,7 @@
 extern struct buffer node_buffer;
 extern int processed_nodes, processed_nodes_out, processed_ways, processed_relations, processed_tiles;
 extern struct item_bin *item_bin;
+extern struct item_bin *item_bin_coastline;
 extern int bytes_read;
 extern int overlap;
 extern int unknown_country;
Index: itembin_buffer.c
===================================================================
--- itembin_buffer.c	(revision 4854)
+++ itembin_buffer.c	(working copy)
@@ -22,8 +22,10 @@
 #include "debug.h"
 
 
-static char buffer[800000];
+static char buffer[8000000];
 struct item_bin *item_bin=(struct item_bin *)(void *)buffer;
+static char buffer_coastline[8000000];
+struct item_bin *item_bin_coastline=(struct item_bin *)(void *)buffer_coastline;
 static struct node_item *node_item=(struct node_item *)(void *)buffer;
 
 struct node_item *
Index: geom.c
===================================================================
--- geom.c	(revision 4854)
+++ geom.c	(working copy)
@@ -620,3 +620,83 @@
 		item_bin_write_clipped(ib_in, param, out);
 	}
 }
+
+
+
+
+static int coord_dot_prod (struct coord* c1, struct coord* c2)
+{
+	return c1->x*c2->x + c1->y*c2->y;
+}
+
+
+static void coord_sub (struct coord* c1, struct coord* c2, struct coord* cout)
+{
+	cout->x = c1->x - c2->x;
+	cout->y = c1->y - c2->y;
+}
+
+int self_intersect_test(struct item_bin*ib)
+{
+	int vertices_count = ib->clen/2;
+	if(vertices_count<4) {
+		return 0;
+	}
+	struct coord*vertices = (struct coord*)(ib+1);
+	int i;
+	for (i = 0; i < vertices_count; ++i) {
+                if (i < vertices_count - 1) {
+		    int h;
+                    for (h = i + 1; h < vertices_count; ++h)
+                    {
+                        // Do two vertices lie on top of one another?
+                        if ( i!=0 && h-i!=1 && h-i!=-1 && vertices[i].x == vertices[h].x && vertices[i].y == vertices[h].y ) {
+                            return 1;
+                        }
+                    }
+                }
+
+                int j = (i + 1) % vertices_count;
+                struct coord iToj;
+		coord_sub(&vertices[j], &vertices[i], &iToj);
+                struct coord iTojNormal;
+		iTojNormal.x =  iToj.y;
+		iTojNormal.y = -iToj.x;
+                // i is the first vertex and j is the second
+                int startK = (j + 1) % vertices_count;
+                int endK = (i - 1 + vertices_count) % vertices_count;
+                endK += startK < endK ? 0 : startK + 1;
+                int k = startK;
+                struct coord iTok; 
+		coord_sub(&vertices[k], &vertices[i], &iTok);
+                int onLeftSide = coord_dot_prod(&iTok, &iTojNormal) >= 0;
+                struct coord prevK = vertices[k];
+                ++k;
+                for (; k <= endK; ++k)
+                {
+                    int modK = k % vertices_count;
+		    coord_sub(&vertices[modK], &vertices[i], &iTok);
+                    if (onLeftSide != coord_dot_prod(&iTok, &iTojNormal) >= 0)
+                    {
+                        struct coord prevKtoK, idiff, jdiff;
+			coord_sub(&vertices[modK], &prevK, &prevKtoK);
+                        struct coord prevKtoKNormal;
+			prevKtoKNormal.x = prevKtoK.y;
+			prevKtoKNormal.y = -prevKtoK.x;
+			coord_sub(&vertices[i],&prevK,&idiff);
+			coord_sub(&vertices[j],&prevK,&jdiff);
+                        if ((coord_dot_prod(&idiff, &prevKtoKNormal) >= 0) != (coord_dot_prod(&jdiff, &prevKtoKNormal) >= 0))
+                        {
+                            if(i!=j-1 && i!=j+1) {
+                               return 1;
+			    }
+                        }
+                    }
+                    onLeftSide = coord_dot_prod(&iTok, &iTojNormal) > 0;
+                    prevK = vertices[modK];
+                }
+            }
+            return 0;
+}
+
+
Index: boundaries.c
===================================================================
--- boundaries.c	(revision 4854)
+++ boundaries.c	(working copy)
@@ -70,6 +70,16 @@
 	while ((ib=read_item(boundaries))) {
 		char *member=NULL;
 		struct boundary *boundary=g_new0(struct boundary, 1);
+
+		//TODO rename natural to a better name
+		boundary->natural = 0; 
+		if( osm_tag_value(ib, "natural") && !strcmp(osm_tag_value(ib, "natural"),"water")) {
+			boundary->natural = 1; 
+		}
+		if( osm_tag_value(ib, "waterway") && !strcmp(osm_tag_value(ib, "waterway"),"riverbank")) {
+			boundary->natural = 1; 
+		}
+
 		char *admin_level=osm_tag_value(ib, "admin_level");
 		char *iso=osm_tag_value(ib, "ISO3166-1");
 		/* disable spain for now since it creates a too large index */
@@ -92,8 +102,9 @@
 			if (sscanf(member,"2:%Ld:%n",&wayid,&read) >= 1) {
 				char *rolestr=member+read;
 				enum geom_poly_segment_type role;
-				if (!strcmp(rolestr,"outer") || !strcmp(rolestr,"exclave"))
+				if (!strcmp(rolestr,"outer") || !strcmp(rolestr,"exclave")) {
 					role=geom_poly_segment_type_way_outer;
+				}
 				else if (!strcmp(rolestr,"inner") || !strcmp(rolestr,"enclave"))
 					role=geom_poly_segment_type_way_inner;
 				else if (!strcmp(rolestr,""))
@@ -202,12 +213,18 @@
 	while (l) {
 		struct boundary *boundary=l->data;
 		int first=1;
-		FILE *f=NULL,*fu=NULL;
+		FILE *f=NULL,*fu=NULL,*coastline=NULL;;
 		if (boundary->country) {
 			char *name=g_strdup_printf("country_%s_poly",boundary->iso2);
 			f=tempfile("",name,1);
 			g_free(name);
 		}
+		int to_write = 0;
+		if (boundary->natural) {
+			coastline=tempfile("","ways_split",2);
+			struct item_bin *ib=item_bin_coastline;
+			item_bin_init(ib, type_poly_water);
+		}
 		boundary->sorted_segments=geom_poly_segments_sort(boundary->segments, geom_poly_segment_type_way_right_side);
 		sl=boundary->sorted_segments;
 		while (sl) {
@@ -228,6 +245,19 @@
 				item_bin_add_coord(ib, gs->first, gs->last-gs->first+1);
 				item_bin_write(ib, f);
 			}
+			if (coastline && gs->type==geom_poly_segment_type_way_outer) {
+				struct item_bin *ib=item_bin_coastline;
+				item_bin_add_coord(ib, gs->first, gs->last-gs->first+1);
+				to_write = 1;
+#if 0
+struct coord*crd = gs->first;
+//printf("\nPTR:%p\n",ib);
+while(crd != gs->last) {
+	printf("CRD:%d %d\n",crd->x,crd->y);
+	crd++;
+}
+#endif
+			}
 			if (boundary->country) {
 				if (!coord_is_equal(*gs->first,*gs->last)) {
 					if (!fu) {
@@ -246,16 +276,38 @@
 			}
 			sl=g_list_next(sl);
 		}	
+
+		if (coastline && to_write ) {
+			struct item_bin *ib=item_bin_coastline;
+			if(0 == self_intersect_test(ib)) {
+				item_bin_write(ib, coastline);
+			} else {
+#if 1
+struct coord*crd = (struct coord*)(ib+1);
+int ii;
+for(ii=0;ii<ib->clen/2;++ii) {
+	printf("CRD:%d %d\n",crd->x,crd->y);
+	crd++;
+}
+#endif
+			}
+			item_bin_init(ib, type_poly_water);
+#if 1
+printf("CRD:\n");
+#endif
+		}
+
 		ret=process_boundaries_insert(ret, boundary);
 		l=g_list_next(l);
 		if (f) 
 			fclose(f);
+		if (coastline) 
+			fclose(coastline);
 		if (fu) {
 			if (boundary->country)
 				osm_warning("relation",item_bin_get_relationid(boundary->ib),0,"Broken country polygon '%s'\n",boundary->iso2);
 			fclose(fu);
 		}
-		
 	}
 #if 0
 	printf("hierarchy\n");